Vulkan-Docs/appendices/invariance.txt

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// Copyright (c) 2015-2019 Khronos Group. This work is licensed under a
Change log for June 24, 2017 Vulkan 1.0.53 spec update: * Bump API patch number and header version number to 53 for this update. Github Issues: Internal Issues: * Clarify mappings of coordinates for mutable, compatible image views in slink:VkImageViewCreateInfo (internal issue 815). * Make ename:VK_BIND_SFR_BIT require a logical device with multiple physical devices, so that standard sparse image block dimensions are only required on systems that support multi-GPU (internal issue 835). * Convert all files from use of // refBegin .. // refEnd comments to delimit ref pages, to use of open blocks, and update style guide accordingly (internal issue 839). * Add valid usage for slink:VkWriteDescriptorSet when performing updates to a ename:VK_STORAGE_IMAGE descriptor with layout ename:VK_IMAGE_LAYOUT_GENERAL. * Add a hack to the validity generator script to support an odd interaction between flink:vkCmdFillBuffer and an extension (internal issue 853). * Remove redundant text describing slink:VkBufferCreateInfo::pname:usage, which was already covered by implicit valid usage (internal issue 854). * Update implicit validity generator script to properly handle the pname:sType and pname:pNext members of "returnedonly" structures (internal issue 874). * Note that slink:VkApplicationInfo::pname:pApplicationName & slink:VkApplicationInfo::pname:pEngineName are optional, and add missing implicit valid usage statements for flink:vkDestroyInstance. * Added missing valid usage for flink:vkCmdWriteTimestamp to require a timestamp query pool. * Simplify and/or split "`non-atomic`" valid usage statements. New Extensions: * `VK_AMD_gpu_shader_int16` * `VK_EXT_blend_operation_advanced` * `VK_EXT_sampler_filter_minmax` * `VK_NV_framebuffer_mixed_samples` ----------------------------------------------------- Note: the 1.0.52 spec wasn't published on github, so the 1.0.53 release combines both change sets. ----------------------------------------------------- Change log for June 13, 2017 Vulkan 1.0.52 spec update: * Bump API patch number and header version number to 52 for this update. Github Issues: Internal Issues: * Clarify behavior when non-coherent memory has <<memory-device-unmap-does-not-flush, not been flushed before being unmapped>> (internal issue 819). * Fix description of code:WorkgroupSize builtin to note it decorates an object, not a variable (internal issue 836). * Fix asciidoc attributes so that trailing '{plus}' symbols in [eq] style equations are rendered properly (internal issue 845). * Add language to the "`Extension Handles, Objects, Enums, and Typedefs`" section of the Procedures and Conventions document stating that any new handle type requires a corresponding entry in the elink:VkObjectType enumerated type (internal issue 856). * Update style guide to use slink macro for Vulkan handle type names, and define narrow conditions under which to use the *name and *text macros instead of *link (internal issue 886). * Add a dependency of the <<VK_KHX_device_group,VK_KHX_device_group>> extension on VK_KHX_device_group_creation to +vk.xml+ and the extension appendix. * Change the copyright on Vulkan specification asciidoc *source* files to CC-BY 4.0, and update the proprietary Khronos copyright applied to the generated *output* formats (internal issue 327). This enables broader re-use and modification of the Vulkan specification sources, while not affecting the Reciprocal IP License between Vulkan Adopters and Working Group Members. New Extensions: * `VK_NV_fill_rectangle` * `VK_NV_fragment_coverage_to_color`
2017-06-27 02:32:10 +00:00
// Creative Commons Attribution 4.0 International License; see
// http://creativecommons.org/licenses/by/4.0/
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[appendix]
[[invariance]]
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= Invariance
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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The Vulkan specification is not pixel exact.
It therefore does not guarantee an exact match between images produced by
different Vulkan implementations.
However, the specification does specify exact matches, in some cases, for
images produced by the same implementation.
The purpose of this appendix is to identify and provide justification for
those cases that require exact matches.
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== Repeatability
The obvious and most fundamental case is repeated issuance of a series of
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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Vulkan commands.
For any given Vulkan and framebuffer state vector, and for any Vulkan
command, the resulting Vulkan and framebuffer state must: be identical
whenever the command is executed on that initial Vulkan and framebuffer
state.
This repeatability requirement does not apply when using shaders containing
side effects (image and buffer variable stores and atomic operations),
because these memory operations are not guaranteed to be processed in a
defined order.
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Change log for August 26, 2016 Vulkan 1.0.25 spec update: * Bump API patch number and header version number to 25 for this update. * Structurally change the specification so that multiple extensions are included in the +1.0+ git branch, and specifications will include or not include those extensions at build time based on options passed to the Makefile. See +doc/specs/vulkan/README.html+ and the ``Layers and Extensions'' section of the ``Vulkan Documentation and Extensions'' document for more information on this change. * Register and publish new extensions in the single-branch form: ** +VK_NV_external_memory_capabilities+ ** +VK_NV_external_memory+ ** +VK_NV_external_memory_win32+ ** +VK_NV_win32_keyed_mutex+ Github Issues: * Clarify description of GetInstanceProcAddr and GetDeviceProcAddr (public issue 212). * Add SPIR-V <<textures-operation-validation, instruction validation>> for single-sampled images (public issue 316). * Fix spelling of ``tesselation'' in a few places and note it as an exception to the American spelling rules convention (public issue 327). * Fix Makefile to create output directory for ``styleguide'' target (public issue 329). * Fix numerous minor issues with incorrectly tags on enumerant names and table titles (public issue 330). * Generate specversion.txt date in UTC time and RFC 2822 format (public issue 335). * Convert link to the SPIR-V Specification for flink:VkShaderModuleCreateInfo into an internal link to the normative reference (public issue 336). * Add ename:VK_ERROR_OUT_OF_MEMORY error code to flink:vkCreateDebugReportCallbackEXT (public issue 337). Internal Issues: * Update style guide regarding use of code:NULL and dname:VK_NULL_HANDLE (internal issue 393). * Change the definition of latexmath:[$q$] in the <<textures-image-level-selection,texture image level selection>> section to be the index of the maximum defined level for the view, not the number of levels in the view (internal issue 406). * Allow developers to override dname:VK_DEFINE_NON_DISPATCHABLE_HANDLE with their own binary-compatible definition (internal issue 439). * Fix +vk_platform.h+ conditional logic causing compile failure with some Android compilers (internal issue 441). * Implement the single-branch model as described above (internal issue 461). Other Issues:
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ifdef::VK_AMD_rasterization_order[]
The repeatability requirement does not apply for rendering done using a
graphics pipeline that uses ename:VK_RASTERIZATION_ORDER_RELAXED_AMD.
endif::VK_AMD_rasterization_order[]
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One purpose of repeatability is avoidance of visual artifacts when a
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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double-buffered scene is redrawn.
If rendering is not repeatable, swapping between two buffers rendered with
the same command sequence may: result in visible changes in the image.
Such false motion is distracting to the viewer.
Another reason for repeatability is testability.
Repeatability, while important, is a weak requirement.
Given only repeatability as a requirement, two scenes rendered with one
(small) polygon changed in position might differ at every pixel.
Such a difference, while within the law of repeatability, is certainly not
within its spirit.
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Additional invariance rules are desirable to ensure useful operation.
== Multi-pass Algorithms
Invariance is necessary for a whole set of useful multi-pass algorithms.
Change log for April 29, 2016 Vulkan 1.0.12 spec update: * Bump API patch number and header version number to 12 for this update. Github Issues: * Change valid usage statements intended to be "sub-points" to be actual sub-points (public issue 66). * Replace double negation in description of slink:VkRenderPassBeginInfo::pname:pClearValues (based on public merge 142). * Cleanup minor typos in spec, ref pages and XML, including those proposed in public pull requests 144, 150, 151, 167, 168, 181, and 186. * Use *strict subset* in describing the partial order of memory property types for slink:VkMemoryType, and update the style guide accordingly (public issue 190). * Fix various "a image" -> "an image" typos (public issue 191). * Note in the <<fundamentals-validusage,Valid Usage>> and <<extensions-interactions,Extension Interactions>> sections that structures defined by extensions which may be passed in structure chains using the ptext:pNext member must: include initial ptext:sType and ptext:pNext members (public issue 192). Internal Issues: * Remove duplicate language from the description of the pname:fence parameter to flink:vkQueueSubmit and improve validity language (internal issue 91). * Added documentation for "optional" attribute to XML readme.tex/pdf (internal issue 149). * Clarify the host-side data validity rules and behavior of flink:vkFlushMappedMemoryRanges and flink:vkInvalidateMappedMemoryRanges (internal issue 266). Other Commits: * Added clarification to flink:vkCmdFillBuffer regarding the use of ename:VK_WHOLE_SIZE. * Fixed and documented implementation of "validextensionstructs" attribute. in XML processing scripts and readme.tex/pdf. * Add missing validity statements to flink:vkResetEvent and flink:vkCmdResetEvent. * Fix validity for the ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT flag. Correct all the draw/dispatch commands to mention optimally tiled images as well as linear tiled images, and say image VIEWS instead of images. Add validity statement to flink:vkCmdBlitImage * Replace the {apiname} macro with hardcoded "Vulkan", now that we've committed to that name. * Add the VK_AMD_rasterization_order extension to vk.xml.
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Such algorithms render multiple times, each time with a different Vulkan
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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mode vector, to eventually produce a result in the framebuffer.
Examples of these algorithms include:
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Change log for February 10, 2017 Vulkan 1.0.40 spec update: * Bump API patch number and header version number to 40 for this update. * There is a major build change in this release. We are now using the Ruby-based ``asciidoctor'' implementation, rather than the Python-based ``asciidoc'' implementation, to process the specification. While the actual specification markup changes were minimal, this requires a new set of build tools and a very different installation process, especially because we now use an experimental direct-to-PDF backend for Asciidoctor instead of Docbook->dblatex->PDF. It is no longer possible to build the Specification using asciidoc. See doc/specs/vulkan/README.adoc for some guidance on installing the new toolchain components. * There are some minor rendering issues in the PDF output due to teething problems with the asciidoctor toolchain, especially with mathematical equations. We are aware of these and working on them. Github Issues: * Updated sample code for the <<sparsememory-examples-basic,sparse resource binding example>> (public issue 97). * Modify line and point clipping behavior in the <<vertexpostproc-clipping, Primitive Clipping>> section to allow for pop-free behavior. The ability to check for which behavior is implemented may be added a future feature or extension (public issue 113). * Unify the discussions of implicit ordering throughout the spec, in particular in the new sections <<drawing-primitive-order, Primitive Order>>, <<primrast-order, Rasterization Order>>, and <<synchronization-implicit, Implicit Synchronization Guarantees>>; the discussion of <<synchronization-submission-order, submission order>>; and references elsewhere to these sections (public issue 133). * Clarify \<\<descriptorsets-compatibility,Pipeline Layout Compatibility>> language and introduce the term ``identically defined'' (public issue 164). * Add a dependency to the +VK_EXT_debug_marker+ extension that's needed to reuse the object type enum from +VK_EXT_debug_report+, and moves the definition of that enum into +VK_EXT_debug_report+ where it should be (public issue 409). * Remove redundant valid usage statement from slink:VkImageBlit (public issue 421). * Update GL_KHR_vulkan_glsl to allow the ternary operator to result in a specialization constant (public issue 424). * Fix valid usage for flink:VkPipelineShaderStageCreateInfo (public issue 426). * Correct typo in New Objects list for <<VK_EXT_debug_report>> (public issue 447). Internal Issues: * Moved to asciidoctor for spec builds (internal issue 121). * Update style guide to describe where to put new extensions-specific asciidoc files, and what to name them (internal issue 626). * Add src/spec/indexExt.py to autogenerate registry index entries linking into the 1.0-extensions specification, instead of maintaining the index manually. (internal issue 642). * Autogenerate extension dependencies and lists of all extensions and all KHR extensions from the "supported" attributes in +vk.xml+. Execute +make config/extDependency.sh+ from +doc/specs/vulkan+ when a supported extension is added to vk.xml, to regenerate the dependency script. The consequence is that specifying a single extension to the +makeExt+ script will automatically enable all extensions it depends on as well, and that the +makeAllExts+ and +makeKHR+ scripts do not need to be updated when a new extension is supported (internal issue 648). * Put extension appendices all at the same asciidoc section level, so KHR WSI extensions show up in the HTML index (internal issue 648). Other Issues: * Imbed images in the generated HTML specs instead of loading them from the images/ directory. * Fix missing EXT in extension name (ename:VK_EXT_SWAPCHAIN_COLOR_SPACE_EXTENSION_NAME). * Add new +VK_EXT_SMPTE_2086_metadata+ extension. * In the <<platformCreateSurface_xlib,Xlib Surface>> section of the +VK_KHR_xlib_surface+ specification, add language warning users that they always need to call code:XinitThreads. * Use the term "presentable image" (rather than "swapchain image") consistently in +VK_KHR_swapchain+ and related extensions, and add a glossary term defining it. * Relocate the valid usage for samples of flink:vkGetPhysicalDeviceSparseImageFormatProperties2KHR::pname:pFormatInfo to be below the flink:VkPhysicalDeviceSparseImageFormatInfo2KHR structure.
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* "`Erasing`" a primitive from the framebuffer by redrawing it, either in
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a different color or using the XOR logical operation.
* Using stencil operations to compute capping planes.
== Invariance Rules
For a given Vulkan device:
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Change log for April 29, 2016 Vulkan 1.0.12 spec update: * Bump API patch number and header version number to 12 for this update. Github Issues: * Change valid usage statements intended to be "sub-points" to be actual sub-points (public issue 66). * Replace double negation in description of slink:VkRenderPassBeginInfo::pname:pClearValues (based on public merge 142). * Cleanup minor typos in spec, ref pages and XML, including those proposed in public pull requests 144, 150, 151, 167, 168, 181, and 186. * Use *strict subset* in describing the partial order of memory property types for slink:VkMemoryType, and update the style guide accordingly (public issue 190). * Fix various "a image" -> "an image" typos (public issue 191). * Note in the <<fundamentals-validusage,Valid Usage>> and <<extensions-interactions,Extension Interactions>> sections that structures defined by extensions which may be passed in structure chains using the ptext:pNext member must: include initial ptext:sType and ptext:pNext members (public issue 192). Internal Issues: * Remove duplicate language from the description of the pname:fence parameter to flink:vkQueueSubmit and improve validity language (internal issue 91). * Added documentation for "optional" attribute to XML readme.tex/pdf (internal issue 149). * Clarify the host-side data validity rules and behavior of flink:vkFlushMappedMemoryRanges and flink:vkInvalidateMappedMemoryRanges (internal issue 266). Other Commits: * Added clarification to flink:vkCmdFillBuffer regarding the use of ename:VK_WHOLE_SIZE. * Fixed and documented implementation of "validextensionstructs" attribute. in XML processing scripts and readme.tex/pdf. * Add missing validity statements to flink:vkResetEvent and flink:vkCmdResetEvent. * Fix validity for the ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT flag. Correct all the draw/dispatch commands to mention optimally tiled images as well as linear tiled images, and say image VIEWS instead of images. Add validity statement to flink:vkCmdBlitImage * Replace the {apiname} macro with hardcoded "Vulkan", now that we've committed to that name. * Add the VK_AMD_rasterization_order extension to vk.xml.
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*Rule 1* _For any given Vulkan and framebuffer state vector, and for any
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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given Vulkan command, the resulting Vulkan and framebuffer state must: be
identical each time the command is executed on that initial Vulkan and
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framebuffer state._
*Rule 2* _Changes to the following state values have no side effects (the
use of any other state value is not affected by the change):_
*Required:*
* _Color and depth/stencil attachment contents_
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* _Scissor parameters (other than enable)_
* _Write masks (color, depth, stencil)_
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* _Clear values (color, depth, stencil)_
*Strongly suggested:*
* _Stencil parameters (other than enable)_
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* _Depth test parameters (other than enable)_
* _Blend parameters (other than enable)_
* _Logical operation parameters (other than enable)_
*Corollary 1* _Fragment generation is invariant with respect to the state
Change log for February 25, 2015 Vulkan 1.0.4 spec update: * Bump API patch number from 3 to 4 for the first public update to the spec. Add patch number to the spec title (this will be done automatically from XML, later). * Fixes for numerous editorial issues. Regularize descriptions of variable-length array queries. Properly tag enumerants so they come out in the right font (many were mislabeled in usage tags in vk.xml, or not tagged). Spelling and markup corrections (public issue 4). * Fix typos and clearly separate description of different types of memory areas (public issue 5). * Use standards-compliant preprocessor guard symbols on headers (public issue 7). * Note that Github users can't currently set labels on issues, and recommend a fallback approach (public issue 15). * Use latexmath prefix on len= attributes (public issue 29). * Make flink:vkCmdUpdateBuffer pname:dataSize limit consistent (public issue 65). * Add VK_KHR_mirror_clamp_to_edge extension to core API branch, as an optional feature not introducing new commands or enums (internal issue 104). * Cleanup invariance language inherited from the GL specification to not refer to nonexistent (GL-specific) state (internal issue 111). * Modify the flink:vkCmdDrawIndexed pname:vertexOffset definition to not be the "base offset within the index buffer" but rather the "value added to the vertex index before indexing into the vertex buffer" (internal issue 118). * Fix drawing chapter in the "Programmable Primitive Shading" section where it described categories of drawing commands. It referenced flink:vkCmdDrawIndexed twice. Replace the second reference with flink:vkCmdDrawIndexedIndirect (internal issue 119). * Typo fixed in <<sparsememory-examples-advanced,Advanced Sparse Resources>> sparse memory example (internal issue 122). * Add flink:VkDisplayPlaneAlphaFlagsKHR to <require> section of VK_KHR_display extension (internal issue 125) * Add missing optional="false,true" to flink:vkGetImageSparseMemoryRequirements pname:pSparseMemoryRequirementCount parameter (internal issue 132) * Rename ename:VK_STRUCTURE_TYPE_DEBUG_REPORT_CREATE_INFO_EXT to ename:VK_STRUCTURE_TYPE_DEBUG_REPORT_CALLBACK_CREATE_INFO_EXT (internal issue 133) * Fix a handful of broken cross-references in the <<samplers,Samplers>> chapter (internal issue 134). * Fix "Input Attachement" GLSL example to use correct syntax (internal issue 135). * Update XML schema and documentation to accomodate recently added attributes for validity. Add some introductory material describing design choices and pointing to the public repository to file issues. * Put include of validity in the core spec extensions chapter on its own line, so that asciidoc is happy. * Fix vertexOffset language to specify that it's the value added to the vertex index before indexing into the vertex buffer, not the base offset within the index buffer. * Fix error in the description of flink:vkCmdNextSubpass.
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values listed in Rule 2._
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*Rule 3* _The arithmetic of each per-fragment operation is invariant except
with respect to parameters that directly control it._
*Corollary 2* _Images rendered into different color attachments of the same
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framebuffer, either simultaneously or separately using the same command
sequence, are pixel identical._
*Rule 4* _Identical pipelines will produce the same result when run multiple
times with the same input.
Change log for February 10, 2017 Vulkan 1.0.40 spec update: * Bump API patch number and header version number to 40 for this update. * There is a major build change in this release. We are now using the Ruby-based ``asciidoctor'' implementation, rather than the Python-based ``asciidoc'' implementation, to process the specification. While the actual specification markup changes were minimal, this requires a new set of build tools and a very different installation process, especially because we now use an experimental direct-to-PDF backend for Asciidoctor instead of Docbook->dblatex->PDF. It is no longer possible to build the Specification using asciidoc. See doc/specs/vulkan/README.adoc for some guidance on installing the new toolchain components. * There are some minor rendering issues in the PDF output due to teething problems with the asciidoctor toolchain, especially with mathematical equations. We are aware of these and working on them. Github Issues: * Updated sample code for the <<sparsememory-examples-basic,sparse resource binding example>> (public issue 97). * Modify line and point clipping behavior in the <<vertexpostproc-clipping, Primitive Clipping>> section to allow for pop-free behavior. The ability to check for which behavior is implemented may be added a future feature or extension (public issue 113). * Unify the discussions of implicit ordering throughout the spec, in particular in the new sections <<drawing-primitive-order, Primitive Order>>, <<primrast-order, Rasterization Order>>, and <<synchronization-implicit, Implicit Synchronization Guarantees>>; the discussion of <<synchronization-submission-order, submission order>>; and references elsewhere to these sections (public issue 133). * Clarify \<\<descriptorsets-compatibility,Pipeline Layout Compatibility>> language and introduce the term ``identically defined'' (public issue 164). * Add a dependency to the +VK_EXT_debug_marker+ extension that's needed to reuse the object type enum from +VK_EXT_debug_report+, and moves the definition of that enum into +VK_EXT_debug_report+ where it should be (public issue 409). * Remove redundant valid usage statement from slink:VkImageBlit (public issue 421). * Update GL_KHR_vulkan_glsl to allow the ternary operator to result in a specialization constant (public issue 424). * Fix valid usage for flink:VkPipelineShaderStageCreateInfo (public issue 426). * Correct typo in New Objects list for <<VK_EXT_debug_report>> (public issue 447). Internal Issues: * Moved to asciidoctor for spec builds (internal issue 121). * Update style guide to describe where to put new extensions-specific asciidoc files, and what to name them (internal issue 626). * Add src/spec/indexExt.py to autogenerate registry index entries linking into the 1.0-extensions specification, instead of maintaining the index manually. (internal issue 642). * Autogenerate extension dependencies and lists of all extensions and all KHR extensions from the "supported" attributes in +vk.xml+. Execute +make config/extDependency.sh+ from +doc/specs/vulkan+ when a supported extension is added to vk.xml, to regenerate the dependency script. The consequence is that specifying a single extension to the +makeExt+ script will automatically enable all extensions it depends on as well, and that the +makeAllExts+ and +makeKHR+ scripts do not need to be updated when a new extension is supported (internal issue 648). * Put extension appendices all at the same asciidoc section level, so KHR WSI extensions show up in the HTML index (internal issue 648). Other Issues: * Imbed images in the generated HTML specs instead of loading them from the images/ directory. * Fix missing EXT in extension name (ename:VK_EXT_SWAPCHAIN_COLOR_SPACE_EXTENSION_NAME). * Add new +VK_EXT_SMPTE_2086_metadata+ extension. * In the <<platformCreateSurface_xlib,Xlib Surface>> section of the +VK_KHR_xlib_surface+ specification, add language warning users that they always need to call code:XinitThreads. * Use the term "presentable image" (rather than "swapchain image") consistently in +VK_KHR_swapchain+ and related extensions, and add a glossary term defining it. * Relocate the valid usage for samples of flink:vkGetPhysicalDeviceSparseImageFormatProperties2KHR::pname:pFormatInfo to be below the flink:VkPhysicalDeviceSparseImageFormatInfo2KHR structure.
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The wording "`Identical pipelines`" means slink:VkPipeline objects that have
been created with identical SPIR-V binaries and identical state, which are
then used by commands executed using the same Vulkan state vector.
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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Invariance is relaxed for shaders with side effects, such as performing
stores or atomics._
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*Rule 5* _All fragment shaders that either conditionally or unconditionally
assign_ code:FragCoord.z _to_ code:FragDepth _are depth-invariant with
respect to each other, for those fragments where the assignment to_
code:FragDepth _actually is done._
Change log for April 29, 2016 Vulkan 1.0.12 spec update: * Bump API patch number and header version number to 12 for this update. Github Issues: * Change valid usage statements intended to be "sub-points" to be actual sub-points (public issue 66). * Replace double negation in description of slink:VkRenderPassBeginInfo::pname:pClearValues (based on public merge 142). * Cleanup minor typos in spec, ref pages and XML, including those proposed in public pull requests 144, 150, 151, 167, 168, 181, and 186. * Use *strict subset* in describing the partial order of memory property types for slink:VkMemoryType, and update the style guide accordingly (public issue 190). * Fix various "a image" -> "an image" typos (public issue 191). * Note in the <<fundamentals-validusage,Valid Usage>> and <<extensions-interactions,Extension Interactions>> sections that structures defined by extensions which may be passed in structure chains using the ptext:pNext member must: include initial ptext:sType and ptext:pNext members (public issue 192). Internal Issues: * Remove duplicate language from the description of the pname:fence parameter to flink:vkQueueSubmit and improve validity language (internal issue 91). * Added documentation for "optional" attribute to XML readme.tex/pdf (internal issue 149). * Clarify the host-side data validity rules and behavior of flink:vkFlushMappedMemoryRanges and flink:vkInvalidateMappedMemoryRanges (internal issue 266). Other Commits: * Added clarification to flink:vkCmdFillBuffer regarding the use of ename:VK_WHOLE_SIZE. * Fixed and documented implementation of "validextensionstructs" attribute. in XML processing scripts and readme.tex/pdf. * Add missing validity statements to flink:vkResetEvent and flink:vkCmdResetEvent. * Fix validity for the ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT flag. Correct all the draw/dispatch commands to mention optimally tiled images as well as linear tiled images, and say image VIEWS instead of images. Add validity statement to flink:vkCmdBlitImage * Replace the {apiname} macro with hardcoded "Vulkan", now that we've committed to that name. * Add the VK_AMD_rasterization_order extension to vk.xml.
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If a sequence of Vulkan commands specifies primitives to be rendered with
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shaders containing side effects (image and buffer variable stores and atomic
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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operations), invariance rules are relaxed.
In particular, rule 1, corollary 2, and rule 4 do not apply in the presence
of shader side effects.
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Change log for April 29, 2016 Vulkan 1.0.12 spec update: * Bump API patch number and header version number to 12 for this update. Github Issues: * Change valid usage statements intended to be "sub-points" to be actual sub-points (public issue 66). * Replace double negation in description of slink:VkRenderPassBeginInfo::pname:pClearValues (based on public merge 142). * Cleanup minor typos in spec, ref pages and XML, including those proposed in public pull requests 144, 150, 151, 167, 168, 181, and 186. * Use *strict subset* in describing the partial order of memory property types for slink:VkMemoryType, and update the style guide accordingly (public issue 190). * Fix various "a image" -> "an image" typos (public issue 191). * Note in the <<fundamentals-validusage,Valid Usage>> and <<extensions-interactions,Extension Interactions>> sections that structures defined by extensions which may be passed in structure chains using the ptext:pNext member must: include initial ptext:sType and ptext:pNext members (public issue 192). Internal Issues: * Remove duplicate language from the description of the pname:fence parameter to flink:vkQueueSubmit and improve validity language (internal issue 91). * Added documentation for "optional" attribute to XML readme.tex/pdf (internal issue 149). * Clarify the host-side data validity rules and behavior of flink:vkFlushMappedMemoryRanges and flink:vkInvalidateMappedMemoryRanges (internal issue 266). Other Commits: * Added clarification to flink:vkCmdFillBuffer regarding the use of ename:VK_WHOLE_SIZE. * Fixed and documented implementation of "validextensionstructs" attribute. in XML processing scripts and readme.tex/pdf. * Add missing validity statements to flink:vkResetEvent and flink:vkCmdResetEvent. * Fix validity for the ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT flag. Correct all the draw/dispatch commands to mention optimally tiled images as well as linear tiled images, and say image VIEWS instead of images. Add validity statement to flink:vkCmdBlitImage * Replace the {apiname} macro with hardcoded "Vulkan", now that we've committed to that name. * Add the VK_AMD_rasterization_order extension to vk.xml.
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The following weaker versions of rules 1 and 4 apply to Vulkan commands
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involving shader side effects:
Change log for April 29, 2016 Vulkan 1.0.12 spec update: * Bump API patch number and header version number to 12 for this update. Github Issues: * Change valid usage statements intended to be "sub-points" to be actual sub-points (public issue 66). * Replace double negation in description of slink:VkRenderPassBeginInfo::pname:pClearValues (based on public merge 142). * Cleanup minor typos in spec, ref pages and XML, including those proposed in public pull requests 144, 150, 151, 167, 168, 181, and 186. * Use *strict subset* in describing the partial order of memory property types for slink:VkMemoryType, and update the style guide accordingly (public issue 190). * Fix various "a image" -> "an image" typos (public issue 191). * Note in the <<fundamentals-validusage,Valid Usage>> and <<extensions-interactions,Extension Interactions>> sections that structures defined by extensions which may be passed in structure chains using the ptext:pNext member must: include initial ptext:sType and ptext:pNext members (public issue 192). Internal Issues: * Remove duplicate language from the description of the pname:fence parameter to flink:vkQueueSubmit and improve validity language (internal issue 91). * Added documentation for "optional" attribute to XML readme.tex/pdf (internal issue 149). * Clarify the host-side data validity rules and behavior of flink:vkFlushMappedMemoryRanges and flink:vkInvalidateMappedMemoryRanges (internal issue 266). Other Commits: * Added clarification to flink:vkCmdFillBuffer regarding the use of ename:VK_WHOLE_SIZE. * Fixed and documented implementation of "validextensionstructs" attribute. in XML processing scripts and readme.tex/pdf. * Add missing validity statements to flink:vkResetEvent and flink:vkCmdResetEvent. * Fix validity for the ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT flag. Correct all the draw/dispatch commands to mention optimally tiled images as well as linear tiled images, and say image VIEWS instead of images. Add validity statement to flink:vkCmdBlitImage * Replace the {apiname} macro with hardcoded "Vulkan", now that we've committed to that name. * Add the VK_AMD_rasterization_order extension to vk.xml.
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*Rule 6* _For any given Vulkan and framebuffer state vector, and for any
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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given Vulkan command, the contents of any framebuffer state not directly or
indirectly affected by results of shader image or buffer variable stores or
atomic operations must: be identical each time the command is executed on
Change log for April 29, 2016 Vulkan 1.0.12 spec update: * Bump API patch number and header version number to 12 for this update. Github Issues: * Change valid usage statements intended to be "sub-points" to be actual sub-points (public issue 66). * Replace double negation in description of slink:VkRenderPassBeginInfo::pname:pClearValues (based on public merge 142). * Cleanup minor typos in spec, ref pages and XML, including those proposed in public pull requests 144, 150, 151, 167, 168, 181, and 186. * Use *strict subset* in describing the partial order of memory property types for slink:VkMemoryType, and update the style guide accordingly (public issue 190). * Fix various "a image" -> "an image" typos (public issue 191). * Note in the <<fundamentals-validusage,Valid Usage>> and <<extensions-interactions,Extension Interactions>> sections that structures defined by extensions which may be passed in structure chains using the ptext:pNext member must: include initial ptext:sType and ptext:pNext members (public issue 192). Internal Issues: * Remove duplicate language from the description of the pname:fence parameter to flink:vkQueueSubmit and improve validity language (internal issue 91). * Added documentation for "optional" attribute to XML readme.tex/pdf (internal issue 149). * Clarify the host-side data validity rules and behavior of flink:vkFlushMappedMemoryRanges and flink:vkInvalidateMappedMemoryRanges (internal issue 266). Other Commits: * Added clarification to flink:vkCmdFillBuffer regarding the use of ename:VK_WHOLE_SIZE. * Fixed and documented implementation of "validextensionstructs" attribute. in XML processing scripts and readme.tex/pdf. * Add missing validity statements to flink:vkResetEvent and flink:vkCmdResetEvent. * Fix validity for the ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT flag. Correct all the draw/dispatch commands to mention optimally tiled images as well as linear tiled images, and say image VIEWS instead of images. Add validity statement to flink:vkCmdBlitImage * Replace the {apiname} macro with hardcoded "Vulkan", now that we've committed to that name. * Add the VK_AMD_rasterization_order extension to vk.xml.
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that initial Vulkan and framebuffer state._
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*Rule 7* _Identical pipelines will produce the same result when run multiple
times with the same input as long as:_
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* _shader invocations do not use image atomic operations;_
* _no framebuffer memory is written to more than once by image stores,
unless all such stores write the same value; and_
* _no shader invocation, or other operation performed to process the
sequence of commands, reads memory written to by an image store._
Change log for January 23, 2017 Vulkan 1.0.39 spec update: * Bump API patch number and header version number to 39 for this update. Github Issues: * Clarified that only accesses via the specified buffer/image subresource ranges are included in the access scopes (public issue 306). * Add missing valid usage statements for flink:vkCreateComputePipelines and flink:vkCreateGraphicsPipelines (public issue 427). Internal Issues: * Add a Note to the <<invariance,Invariance>> appendix about a difference between OpenGL and Vulkan with regards to how primitives derived from offsets are handled (internal issue 355). * Add the +<<VK_KHR_get_physical_device_properties2>>+, +<<VK_KHR_maintenance1>>+, and +<<VK_KHR_shader_draw_parameters>>+ extensions (internal issue 448). * Add the +<<VK_EXT_shader_subgroup_vote>>+ and +<<VK_EXT_shader_subgroup_ballot>>+ extensions (internal issue 449). * Update the texture level-of-detail equation in the <<textures-scale-factor,Scale Factor Operation>> section to better approximate the ellipse major and minor axes (internal issue 547). * Forbid non-explicitly allowed uses of interface decorations in the introduction to the <<interfaces,Shader Interfaces>> chapter (internal issue 607). * Replace use of MathJax with KaTeX, for improved load-time performance as well as avoiding the scrolling-and-scrolling behavior due to MathJax asynchronous rendering when loading at an anchor inside the spec. This change also requires moving to HTML5 output for the spec instead of XHTML, and there is a visible difference in that the chapter navigation index is now in a scrollable sidebar instead of at the top of the document. We may or may not retain the nav sidebar based on feedback (internal issue 613). * Improve consistency of markup and formatting in extension appendices (internal issue 631). Other Issues: * Add explicit valid usage statements to slink:VkImageCopy requiring that the source and destination layer ranges be contained in their respective source and destination images. * Add valid usage language for swapchain of flink:vkAcquireNextImage. If the swapchain has been replaced, then it should not be passed to flink:vkAcquireNextImage. * Add a valid usage statement to flink:vkCreateImageView, that the image must have been created with an appropriate usage bit set. * Noted that slink:VkDisplayPresentInfoKHR is a valid extension of slink:VkPresentInfoKHR in the <<wsi_swapchain,WSI Swapchain>> section. * Update valid usage for flink:vkCmdSetViewport and flink:vkCmdSetScissor to account for the multiple viewport feature. If the feature is not enabled, the parameters for these functions have required values that are defined in the <<features-features-multiViewport,multiple viewports>> section of the spec but were not reflected in the valid usage text for these functions. * Add the +<<VK_EXT_swapchain_colorspace>>+ extension defining common color spaces.
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[NOTE]
.Note
Change log for January 15, 2018 Vulkan 1.0.68 spec update: * Bump API patch number and header version number to 68 for this update. Github Issues: * Added more details in the <<extended-functionality-extensions-compatibility, Extension Compatibility>> section, allowing explicit incompatibilities, and simplify corresponding language in the style guide, which now defers to the API Specification on this point (public issue 638). * Fix typo in description of slink:VkCommandBufferLevel::pname:level (public issue 651). * Only include extension-dependent valid usage statement for slink:VkImageSubresourceRange, and note that the extension names for header files described in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section are only valid links, when the specification being viewed is built with the corresponding extensions enabled (public issue 652). Internal Issues: * Add language to elink:VkResult specifying that when commands return an error, output parameter contents are undefined instead of unmodified (except for pname:sType and pname:pNext). Note that this is a behavior change. Add notes calling out slink:VkImageFormatProperties as an exception (internal issue 1118). * Add "`general-purpose`" to the style guide, and correct existing uses of "`general purpose`" as an adjective (internal issue 1121). * Add the ename:VK_DEBUG_REPORT_OBJECT_TYPE_VALIDATION_CACHE_EXT_EXT token for the `VK_EXT_validation_cache` extension, following the same naming pattern as other tokens in the extension, but keep the old ename:VK_DEBUG_REPORT_OBJECT_TYPE_VALIDATION_CACHE_EXT token around for backwards compatibility (internal issue 1126). Other Issues: * Specify that flink:vkCmdSetDiscardRectangleEXT does not affect copies or clears, matching existing language for the scissor rectangle test. * Move the <<boilerplate-sType, pname:sType>> definition from the boilerplate appendix to the Fundamentals chapter, putting it together with the valid usage of pname:sType rather than having the definition split across two places. * Inline all of the etext:Vk*Flags definitions, moving each one from the boilerplate appendix to appear either after the corresponding etext:Vk*FlagBits value if one is defined, or after the first structure that includes them if not.
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====
Change log for January 23, 2017 Vulkan 1.0.39 spec update: * Bump API patch number and header version number to 39 for this update. Github Issues: * Clarified that only accesses via the specified buffer/image subresource ranges are included in the access scopes (public issue 306). * Add missing valid usage statements for flink:vkCreateComputePipelines and flink:vkCreateGraphicsPipelines (public issue 427). Internal Issues: * Add a Note to the <<invariance,Invariance>> appendix about a difference between OpenGL and Vulkan with regards to how primitives derived from offsets are handled (internal issue 355). * Add the +<<VK_KHR_get_physical_device_properties2>>+, +<<VK_KHR_maintenance1>>+, and +<<VK_KHR_shader_draw_parameters>>+ extensions (internal issue 448). * Add the +<<VK_EXT_shader_subgroup_vote>>+ and +<<VK_EXT_shader_subgroup_ballot>>+ extensions (internal issue 449). * Update the texture level-of-detail equation in the <<textures-scale-factor,Scale Factor Operation>> section to better approximate the ellipse major and minor axes (internal issue 547). * Forbid non-explicitly allowed uses of interface decorations in the introduction to the <<interfaces,Shader Interfaces>> chapter (internal issue 607). * Replace use of MathJax with KaTeX, for improved load-time performance as well as avoiding the scrolling-and-scrolling behavior due to MathJax asynchronous rendering when loading at an anchor inside the spec. This change also requires moving to HTML5 output for the spec instead of XHTML, and there is a visible difference in that the chapter navigation index is now in a scrollable sidebar instead of at the top of the document. We may or may not retain the nav sidebar based on feedback (internal issue 613). * Improve consistency of markup and formatting in extension appendices (internal issue 631). Other Issues: * Add explicit valid usage statements to slink:VkImageCopy requiring that the source and destination layer ranges be contained in their respective source and destination images. * Add valid usage language for swapchain of flink:vkAcquireNextImage. If the swapchain has been replaced, then it should not be passed to flink:vkAcquireNextImage. * Add a valid usage statement to flink:vkCreateImageView, that the image must have been created with an appropriate usage bit set. * Noted that slink:VkDisplayPresentInfoKHR is a valid extension of slink:VkPresentInfoKHR in the <<wsi_swapchain,WSI Swapchain>> section. * Update valid usage for flink:vkCmdSetViewport and flink:vkCmdSetScissor to account for the multiple viewport feature. If the feature is not enabled, the parameters for these functions have required values that are defined in the <<features-features-multiViewport,multiple viewports>> section of the spec but were not reflected in the valid usage text for these functions. * Add the +<<VK_EXT_swapchain_colorspace>>+ extension defining common color spaces.
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The OpenGL spec has the following invariance rule: Consider a primitive p'
obtained by translating a primitive p through an offset (x, y) in window
coordinates, where x and y are integers.
Change log for March 17, 2017 Vulkan 1.0.44 spec update: * Bump API patch number and header version number to 44 for this update. Github Issues: * Fix description of <<features-extentperimagetype, Allowed Extent Values Based On Image Type>> (public issue 290). * Better specify VK_DEVICE_LOST behavior around flink:vkQueueSubmit, flink:vkWaitForFences, and flink:vkGetFenceStatus (public issue 423). * Clarify definition of flink:vkGetQueryPoolResults::pname:queryCount (public issue 441). * Simplify and clean up normative language. Remove shall and replace recommend and variants with should wherever possible (public issue 448). * Fix all dangling internal cross-references in the 1.0-extensions specification, and add scripts/checkXrefs to find these in the future (public issue 456). * Reverse order of ChangeLog.txt entries so the most recent version is documented first (public issue 463) * Removes "become invalid" which clashes with invalid state for command buffers. (public issue 467) * Disallowed pending state in spec text for vkResetCommandBuffer, matching valid usage (public issue 468) * Removes sentence describing invalid state "like initial state". (public issue 469) * Disallows begin command buffer from resetting command buffers in the "recording" state. (public issue 470) * Removes mention of state from description of VK_COMMAND_POOL_CREATE_RESET_COMMAND_BUFFER_BIT (public issue 471) * Removed extra valid usage statement in VkSubmitInfo (public issue 472) Internal Issues: * Clarify description of the pname:imageLayout member of sname:VkDescriptorImageInfo. * Fix typos where etext:VK_VIEW_TYPE* was used instead of etext:VK_IMAGE_VIEW_TYPE. * Removed the <<VK_KHR_display>> and <<VK_KHR_display_swapchain>> example code from the specification and noted it has been moved to the Vulkan SDK cube demo (internal issue 179). * Reorder VkExternalMemoryHandleTypeFlagBitsNV description (internal issue 480). * Clarify than an implementation is <<fundamentals-validusage-flags,permitted to return 'undefined' bit flags>> in a bitfield (internal issue 640). * Break Valid Usage statements describing unrelated parameters into separate statements, and add a style guide entry to follow this approach (internal issue 685). * Move valid usage statement for slink:VkImageCreateInfo from spec body to the explicit valid usage block (internal issue 693). * Fix typos in the descriptions of slink:VkDisplaySurfaceCreateInfoKHR, flink:vkCreateDisplayModeKHR, and flink:vkGetDisplayPlaneSupportedDisplaysKHR in the <<display,Presenting Directly to Display Devices>> section (internal issue 698, 704, 716). * Clarified that mandatory depth/stencil formats are only a requirement for 2D images (internal issue 719). * Clarify that variables decorated with DeviceIndex/ViewIndex must be in the Input storage class (internal issue 733). * Work around generator script problem with removal of Unicode literals from Python 3.0-3.2 using `future` package (internal issue 737). * Remove nonexistent structure type enums from vk.xml (internal issue 738). * Fix validextensionstructs attributes for structures in the pname:pNext chain for VkPresentInfoKHR, fixing implicit valid usage statements for those structures (internal issue 740). New Extensions:
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As long as neither p' nor p is clipped, it must: be the case that each
Change log for January 23, 2017 Vulkan 1.0.39 spec update: * Bump API patch number and header version number to 39 for this update. Github Issues: * Clarified that only accesses via the specified buffer/image subresource ranges are included in the access scopes (public issue 306). * Add missing valid usage statements for flink:vkCreateComputePipelines and flink:vkCreateGraphicsPipelines (public issue 427). Internal Issues: * Add a Note to the <<invariance,Invariance>> appendix about a difference between OpenGL and Vulkan with regards to how primitives derived from offsets are handled (internal issue 355). * Add the +<<VK_KHR_get_physical_device_properties2>>+, +<<VK_KHR_maintenance1>>+, and +<<VK_KHR_shader_draw_parameters>>+ extensions (internal issue 448). * Add the +<<VK_EXT_shader_subgroup_vote>>+ and +<<VK_EXT_shader_subgroup_ballot>>+ extensions (internal issue 449). * Update the texture level-of-detail equation in the <<textures-scale-factor,Scale Factor Operation>> section to better approximate the ellipse major and minor axes (internal issue 547). * Forbid non-explicitly allowed uses of interface decorations in the introduction to the <<interfaces,Shader Interfaces>> chapter (internal issue 607). * Replace use of MathJax with KaTeX, for improved load-time performance as well as avoiding the scrolling-and-scrolling behavior due to MathJax asynchronous rendering when loading at an anchor inside the spec. This change also requires moving to HTML5 output for the spec instead of XHTML, and there is a visible difference in that the chapter navigation index is now in a scrollable sidebar instead of at the top of the document. We may or may not retain the nav sidebar based on feedback (internal issue 613). * Improve consistency of markup and formatting in extension appendices (internal issue 631). Other Issues: * Add explicit valid usage statements to slink:VkImageCopy requiring that the source and destination layer ranges be contained in their respective source and destination images. * Add valid usage language for swapchain of flink:vkAcquireNextImage. If the swapchain has been replaced, then it should not be passed to flink:vkAcquireNextImage. * Add a valid usage statement to flink:vkCreateImageView, that the image must have been created with an appropriate usage bit set. * Noted that slink:VkDisplayPresentInfoKHR is a valid extension of slink:VkPresentInfoKHR in the <<wsi_swapchain,WSI Swapchain>> section. * Update valid usage for flink:vkCmdSetViewport and flink:vkCmdSetScissor to account for the multiple viewport feature. If the feature is not enabled, the parameters for these functions have required values that are defined in the <<features-features-multiViewport,multiple viewports>> section of the spec but were not reflected in the valid usage text for these functions. * Add the +<<VK_EXT_swapchain_colorspace>>+ extension defining common color spaces.
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fragment f' produced from p' is identical to a corresponding fragment f from
p except that the center of f' is offset by (x, y) from the center of f.
This rule does not apply to Vulkan and is an intentional difference from
OpenGL.
Change log for January 15, 2018 Vulkan 1.0.68 spec update: * Bump API patch number and header version number to 68 for this update. Github Issues: * Added more details in the <<extended-functionality-extensions-compatibility, Extension Compatibility>> section, allowing explicit incompatibilities, and simplify corresponding language in the style guide, which now defers to the API Specification on this point (public issue 638). * Fix typo in description of slink:VkCommandBufferLevel::pname:level (public issue 651). * Only include extension-dependent valid usage statement for slink:VkImageSubresourceRange, and note that the extension names for header files described in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section are only valid links, when the specification being viewed is built with the corresponding extensions enabled (public issue 652). Internal Issues: * Add language to elink:VkResult specifying that when commands return an error, output parameter contents are undefined instead of unmodified (except for pname:sType and pname:pNext). Note that this is a behavior change. Add notes calling out slink:VkImageFormatProperties as an exception (internal issue 1118). * Add "`general-purpose`" to the style guide, and correct existing uses of "`general purpose`" as an adjective (internal issue 1121). * Add the ename:VK_DEBUG_REPORT_OBJECT_TYPE_VALIDATION_CACHE_EXT_EXT token for the `VK_EXT_validation_cache` extension, following the same naming pattern as other tokens in the extension, but keep the old ename:VK_DEBUG_REPORT_OBJECT_TYPE_VALIDATION_CACHE_EXT token around for backwards compatibility (internal issue 1126). Other Issues: * Specify that flink:vkCmdSetDiscardRectangleEXT does not affect copies or clears, matching existing language for the scissor rectangle test. * Move the <<boilerplate-sType, pname:sType>> definition from the boilerplate appendix to the Fundamentals chapter, putting it together with the valid usage of pname:sType rather than having the definition split across two places. * Inline all of the etext:Vk*Flags definitions, moving each one from the boilerplate appendix to appear either after the corresponding etext:Vk*FlagBits value if one is defined, or after the first structure that includes them if not.
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====
Change log for January 23, 2017 Vulkan 1.0.39 spec update: * Bump API patch number and header version number to 39 for this update. Github Issues: * Clarified that only accesses via the specified buffer/image subresource ranges are included in the access scopes (public issue 306). * Add missing valid usage statements for flink:vkCreateComputePipelines and flink:vkCreateGraphicsPipelines (public issue 427). Internal Issues: * Add a Note to the <<invariance,Invariance>> appendix about a difference between OpenGL and Vulkan with regards to how primitives derived from offsets are handled (internal issue 355). * Add the +<<VK_KHR_get_physical_device_properties2>>+, +<<VK_KHR_maintenance1>>+, and +<<VK_KHR_shader_draw_parameters>>+ extensions (internal issue 448). * Add the +<<VK_EXT_shader_subgroup_vote>>+ and +<<VK_EXT_shader_subgroup_ballot>>+ extensions (internal issue 449). * Update the texture level-of-detail equation in the <<textures-scale-factor,Scale Factor Operation>> section to better approximate the ellipse major and minor axes (internal issue 547). * Forbid non-explicitly allowed uses of interface decorations in the introduction to the <<interfaces,Shader Interfaces>> chapter (internal issue 607). * Replace use of MathJax with KaTeX, for improved load-time performance as well as avoiding the scrolling-and-scrolling behavior due to MathJax asynchronous rendering when loading at an anchor inside the spec. This change also requires moving to HTML5 output for the spec instead of XHTML, and there is a visible difference in that the chapter navigation index is now in a scrollable sidebar instead of at the top of the document. We may or may not retain the nav sidebar based on feedback (internal issue 613). * Improve consistency of markup and formatting in extension appendices (internal issue 631). Other Issues: * Add explicit valid usage statements to slink:VkImageCopy requiring that the source and destination layer ranges be contained in their respective source and destination images. * Add valid usage language for swapchain of flink:vkAcquireNextImage. If the swapchain has been replaced, then it should not be passed to flink:vkAcquireNextImage. * Add a valid usage statement to flink:vkCreateImageView, that the image must have been created with an appropriate usage bit set. * Noted that slink:VkDisplayPresentInfoKHR is a valid extension of slink:VkPresentInfoKHR in the <<wsi_swapchain,WSI Swapchain>> section. * Update valid usage for flink:vkCmdSetViewport and flink:vkCmdSetScissor to account for the multiple viewport feature. If the feature is not enabled, the parameters for these functions have required values that are defined in the <<features-features-multiViewport,multiple viewports>> section of the spec but were not reflected in the valid usage text for these functions. * Add the +<<VK_EXT_swapchain_colorspace>>+ extension defining common color spaces.
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Change log for April 29, 2016 Vulkan 1.0.12 spec update: * Bump API patch number and header version number to 12 for this update. Github Issues: * Change valid usage statements intended to be "sub-points" to be actual sub-points (public issue 66). * Replace double negation in description of slink:VkRenderPassBeginInfo::pname:pClearValues (based on public merge 142). * Cleanup minor typos in spec, ref pages and XML, including those proposed in public pull requests 144, 150, 151, 167, 168, 181, and 186. * Use *strict subset* in describing the partial order of memory property types for slink:VkMemoryType, and update the style guide accordingly (public issue 190). * Fix various "a image" -> "an image" typos (public issue 191). * Note in the <<fundamentals-validusage,Valid Usage>> and <<extensions-interactions,Extension Interactions>> sections that structures defined by extensions which may be passed in structure chains using the ptext:pNext member must: include initial ptext:sType and ptext:pNext members (public issue 192). Internal Issues: * Remove duplicate language from the description of the pname:fence parameter to flink:vkQueueSubmit and improve validity language (internal issue 91). * Added documentation for "optional" attribute to XML readme.tex/pdf (internal issue 149). * Clarify the host-side data validity rules and behavior of flink:vkFlushMappedMemoryRanges and flink:vkInvalidateMappedMemoryRanges (internal issue 266). Other Commits: * Added clarification to flink:vkCmdFillBuffer regarding the use of ename:VK_WHOLE_SIZE. * Fixed and documented implementation of "validextensionstructs" attribute. in XML processing scripts and readme.tex/pdf. * Add missing validity statements to flink:vkResetEvent and flink:vkCmdResetEvent. * Fix validity for the ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT flag. Correct all the draw/dispatch commands to mention optimally tiled images as well as linear tiled images, and say image VIEWS instead of images. Add validity statement to flink:vkCmdBlitImage * Replace the {apiname} macro with hardcoded "Vulkan", now that we've committed to that name. * Add the VK_AMD_rasterization_order extension to vk.xml.
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When any sequence of Vulkan commands triggers shader invocations that
perform image stores or atomic operations, and subsequent Vulkan commands
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read the memory written by those shader invocations, these operations must:
be explicitly synchronized.
== Tessellation Invariance
When using a pipeline containing tessellation evaluation shaders, the
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fixed-function tessellation primitive generator consumes the input patch
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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specified by an application and emits a new set of primitives.
The following invariance rules are intended to provide repeatability
guarantees.
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Additionally, they are intended to allow an application with a carefully
crafted tessellation evaluation shader to ensure that the sets of triangles
generated for two adjacent patches have identical vertices along shared
Change log for February 10, 2017 Vulkan 1.0.40 spec update: * Bump API patch number and header version number to 40 for this update. * There is a major build change in this release. We are now using the Ruby-based ``asciidoctor'' implementation, rather than the Python-based ``asciidoc'' implementation, to process the specification. While the actual specification markup changes were minimal, this requires a new set of build tools and a very different installation process, especially because we now use an experimental direct-to-PDF backend for Asciidoctor instead of Docbook->dblatex->PDF. It is no longer possible to build the Specification using asciidoc. See doc/specs/vulkan/README.adoc for some guidance on installing the new toolchain components. * There are some minor rendering issues in the PDF output due to teething problems with the asciidoctor toolchain, especially with mathematical equations. We are aware of these and working on them. Github Issues: * Updated sample code for the <<sparsememory-examples-basic,sparse resource binding example>> (public issue 97). * Modify line and point clipping behavior in the <<vertexpostproc-clipping, Primitive Clipping>> section to allow for pop-free behavior. The ability to check for which behavior is implemented may be added a future feature or extension (public issue 113). * Unify the discussions of implicit ordering throughout the spec, in particular in the new sections <<drawing-primitive-order, Primitive Order>>, <<primrast-order, Rasterization Order>>, and <<synchronization-implicit, Implicit Synchronization Guarantees>>; the discussion of <<synchronization-submission-order, submission order>>; and references elsewhere to these sections (public issue 133). * Clarify \<\<descriptorsets-compatibility,Pipeline Layout Compatibility>> language and introduce the term ``identically defined'' (public issue 164). * Add a dependency to the +VK_EXT_debug_marker+ extension that's needed to reuse the object type enum from +VK_EXT_debug_report+, and moves the definition of that enum into +VK_EXT_debug_report+ where it should be (public issue 409). * Remove redundant valid usage statement from slink:VkImageBlit (public issue 421). * Update GL_KHR_vulkan_glsl to allow the ternary operator to result in a specialization constant (public issue 424). * Fix valid usage for flink:VkPipelineShaderStageCreateInfo (public issue 426). * Correct typo in New Objects list for <<VK_EXT_debug_report>> (public issue 447). Internal Issues: * Moved to asciidoctor for spec builds (internal issue 121). * Update style guide to describe where to put new extensions-specific asciidoc files, and what to name them (internal issue 626). * Add src/spec/indexExt.py to autogenerate registry index entries linking into the 1.0-extensions specification, instead of maintaining the index manually. (internal issue 642). * Autogenerate extension dependencies and lists of all extensions and all KHR extensions from the "supported" attributes in +vk.xml+. Execute +make config/extDependency.sh+ from +doc/specs/vulkan+ when a supported extension is added to vk.xml, to regenerate the dependency script. The consequence is that specifying a single extension to the +makeExt+ script will automatically enable all extensions it depends on as well, and that the +makeAllExts+ and +makeKHR+ scripts do not need to be updated when a new extension is supported (internal issue 648). * Put extension appendices all at the same asciidoc section level, so KHR WSI extensions show up in the HTML index (internal issue 648). Other Issues: * Imbed images in the generated HTML specs instead of loading them from the images/ directory. * Fix missing EXT in extension name (ename:VK_EXT_SWAPCHAIN_COLOR_SPACE_EXTENSION_NAME). * Add new +VK_EXT_SMPTE_2086_metadata+ extension. * In the <<platformCreateSurface_xlib,Xlib Surface>> section of the +VK_KHR_xlib_surface+ specification, add language warning users that they always need to call code:XinitThreads. * Use the term "presentable image" (rather than "swapchain image") consistently in +VK_KHR_swapchain+ and related extensions, and add a glossary term defining it. * Relocate the valid usage for samples of flink:vkGetPhysicalDeviceSparseImageFormatProperties2KHR::pname:pFormatInfo to be below the flink:VkPhysicalDeviceSparseImageFormatInfo2KHR structure.
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patch edges, avoiding "`cracks`" caused by minor differences in the
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positions of vertices along shared edges.
*Rule 1* _When processing two patches with identical outer and inner
tessellation levels, the tessellation primitive generator will emit an
identical set of point, line, or triangle primitives as long as the pipeline
used to process the patch primitives has tessellation evaluation shaders
specifying the same tessellation mode, spacing, vertex order, and point mode
decorations.
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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Two sets of primitives are considered identical if and only if they contain
the same number and type of primitives and the generated tessellation
coordinates for the vertex numbered m of the primitive numbered n are
identical for all values of m and n._
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*Rule 2* _The set of vertices generated along the outer edge of the
subdivided primitive in triangle and quad tessellation, and the tessellation
coordinates of each, depends only on the corresponding outer tessellation
level and the spacing decorations in the tessellation shaders of the
pipeline._
*Rule 3* _The set of vertices generated when subdividing any outer primitive
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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edge is always symmetric.
For triangle tessellation, if the subdivision generates a vertex with
tessellation coordinates of the form (0, x, 1-x), (x, 0, 1-x), or (x, 1-x,
0), it will also generate a vertex with coordinates of exactly (0, 1-x, x),
(1-x, 0, x), or (1-x, x, 0), respectively.
For quad tessellation, if the subdivision generates a vertex with
coordinates of (x, 0) or (0, x), it will also generate a vertex with
coordinates of exactly (1-x, 0) or (0, 1-x), respectively.
For isoline tessellation, if it generates vertices at (0, x) and (1, x)
where x is not zero, it will also generate vertices at exactly (0, 1-x) and
(1, 1-x), respectively._
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*Rule 4* _The set of vertices generated when subdividing outer edges in
triangular and quad tessellation must: be independent of the specific edge
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
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subdivided, given identical outer tessellation levels and spacing.
For example, if vertices at (x, 1 - x, 0) and (1-x, x, 0) are generated when
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subdividing the w = 0 edge in triangular tessellation, vertices must: be
generated at (x, 0, 1-x) and (1-x, 0, x) when subdividing an otherwise
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
2016-09-24 07:58:11 +00:00
identical v = 0 edge.
For quad tessellation, if vertices at (x, 0) and (1-x, 0) are generated when
subdividing the v = 0 edge, vertices must: be generated at (0, x) and (0,
1-x) when subdividing an otherwise identical u = 0 edge._
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*Rule 5* _When processing two patches that are identical in all respects
enumerated in rule 1 except for vertex order, the set of triangles generated
for triangle and quad tessellation must: be identical except for vertex and
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
2016-09-24 07:58:11 +00:00
triangle order.
For each triangle n1 produced by processing the first patch, there must: be
a triangle n2 produced when processing the second patch each of whose
vertices has the same tessellation coordinates as one of the vertices in
n1._
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*Rule 6* _When processing two patches that are identical in all respects
enumerated in rule 1 other than matching outer tessellation levels and/or
vertex order, the set of interior triangles generated for triangle and quad
tessellation must: be identical in all respects except for vertex and
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
2016-09-24 07:58:11 +00:00
triangle order.
For each interior triangle n1 produced by processing the first patch, there
must: be a triangle n2 produced when processing the second patch each of
whose vertices has the same tessellation coordinates as one of the vertices
in n1.
A triangle produced by the tessellator is considered an interior triangle if
none of its vertices lie on an outer edge of the subdivided primitive._
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*Rule 7* _For quad and triangle tessellation, the set of triangles
connecting an inner and outer edge depends only on the inner and outer
tessellation levels corresponding to that edge and the spacing decorations._
Change log for September 23, 2016 Vulkan 1.0.28 spec update: * Bump API patch number and header version number to 28 for this update. Github Issues: * Minor spelling and typography cleanup, add definitions of ename:VK_FALSE and ename:VK_TRUE as just what their names say (public issues 220, 318, 325, 365; internal issues 451, 496) * Clarify that the pname:maxDescriptorSet limits in the <<features-limits-required,Required Limits>> table are n * maxPerStage limit (where n=number of supported stages) (public issue 254). * Minor cleanup to <<boilerplate-platform-macros,Platform-Specific Macro Definitions>> appendix (public issue 314). * Add valid usage statement to slink:VkPipelineLayoutCreateInfo disallowing multiple push constant ranges for the same shader stage (public issue 340). * Clarify the elink:VkSharingMode description of what executing the "same" barriers means in case of ownership transfer (public issue 347). * Rename copyright.txt and add COPYING.md to try and reduce confusion about applicable copyrights (public issue 350). * Extend the table in the <<boilerplate-wsi-header, Window System-Specific Header Control>> section to describe the external headers included when each etext:VK_USE_PLATFORM_* macro is defined (public issue 376). Internal Issues: * Add "Revision History" to the PDF outputs following the table of contents, to match HTML outputs (internal issue 43). * Clarified that flink:vkMapMemory may fail due to virtual address space limitations (internal issue 346). * Add +refBody+ comment markup for ref page autoextraction when required (internal issue 400). * Document proper use of "mipmap" and "mip" in the style guide API naming rules, matching the spelling rules (internal issue 471). * Tweak the <<extensions,Layers and Extensions>> appendix to note that the Specification may be built with arbitrary combinations of extensions (internal issue 483). * Remove incorrect statement allowing slink:VkClearAttachment::pname:colorAttachment to be >= slink:VkSubpassDescription::pname:colorAttachmentCount (internal issue 488). * The <<features-limits-viewportboundsrange,viewportBoundsRange>> is expressed in terms of the pname:maxViewportDimensions but this is actually two values. Clarify that it's based on the larger of the two (if they differ) (internal issue 499). Other Issues: * Reflowed text of the entire spec using the 'reflow' Makefile gater, to (hopefully) reduce future internal git churn as edits are made and extensions added in return for one-time pain. This has no perceptible change on the spec outputs but considerable changes on the asciidoc source (internal issue 367).
2016-09-24 07:58:11 +00:00
*Rule 8* _The value of all defined components of_ code:TessCoord _will be in
the range [0, 1].
Additionally, for any defined component x of_ code:TessCoord, _the results
of computing 1.0-x in a tessellation evaluation shader will be exact.
If any floating-point values in the range [0, 1] fail to satisfy this
property, such values must: not be used as tessellation coordinate
components._