mirror of
https://github.com/status-im/Vulkan-Docs.git
synced 2025-01-22 04:09:25 +00:00
e24e42dcff
* Update release number to 91.
Public Issues:
* Update Ubuntu subsystem build instructions in `BUILD.adoc` (public pull
request 624).
* Delete the `VK_KHR_mir_surface` extension from the Specification and
XML, due to EOL of the only driver known to have supported it, and
near-EOL of Mir itself (public issue 814).
* Fix options for some figures that were using old ones (public pull
request 841).
* Fix various accidentally repeated words (public pull request 843).
* Use `time.process_time()`, introduced in Python 3.3, in the scripts
instead of `time.clock()`, which will be removed in Python 3.8 (public
pull request 844).
Internal Issues:
* Update valid usage statements for
`VK_ANDROID_external_memory_android_hardware_buffer` in
slink:VkMemoryAllocateInfo,
slink:VkImportAndroidHardwareBufferInfoANDROID, and
flink:vkGetAndroidHardwareBufferPropertiesANDROID to actually be
verifiable (internal issue 1419).
* Update valid usage statements for
`VK_ANDROID_external_memory_android_hardware_buffer` in
slink:VkMemoryAllocateInfo, slink:VkImageCreateInfo, and
slink:VkImageViewCreateInfo to move valid usage statements in
doubly-nested bullet points up one level, accomodating limitations of
the valid usage extraction script that creates `validusage.json`
(internal issue 1434).
* Fix typo etext:VK_ACCESS_SHADING_RATE_IMAGE_BIT_NV to the correct
ename:VK_ACCESS_SHADING_RATE_IMAGE_READ_BIT_NV.
* Add missing etext:VK_STRUCTURE_TYPE_* tokens to appendices for
extensions missing them.
New Extensions:
* `VK_AMD_memory_overallocation_behavior`
* `VK_NV_ray_tracing`, replacing `VK_NVX_raytracing`
78 lines
2.7 KiB
Plaintext
78 lines
2.7 KiB
Plaintext
include::meta/VK_NV_framebuffer_mixed_samples.txt[]
|
|
|
|
*Last Modified Date*::
|
|
2017-06-04
|
|
*Contributors*::
|
|
- Jeff Bolz, NVIDIA
|
|
|
|
This extension allows multisample rendering with a raster and depth/stencil
|
|
sample count that is larger than the color sample count.
|
|
Rasterization and the results of the depth and stencil tests together
|
|
determine the portion of a pixel that is "`covered`".
|
|
It can be useful to evaluate coverage at a higher frequency than color
|
|
samples are stored.
|
|
This coverage is then "`reduced`" to a collection of covered color samples,
|
|
each having an opacity value corresponding to the fraction of the color
|
|
sample covered.
|
|
The opacity can optionally be blended into individual color samples.
|
|
|
|
Rendering with fewer color samples than depth/stencil samples greatly
|
|
reduces the amount of memory and bandwidth consumed by the color buffer.
|
|
However, converting the coverage values into opacity introduces artifacts
|
|
where triangles share edges and may: not be suitable for normal triangle
|
|
mesh rendering.
|
|
|
|
One expected use case for this functionality is Stencil-then-Cover path
|
|
rendering (similar to the OpenGL GL_NV_path_rendering extension).
|
|
The stencil step determines the coverage (in the stencil buffer) for an
|
|
entire path at the higher sample frequency, and then the cover step draws
|
|
the path into the lower frequency color buffer using the coverage
|
|
information to antialias path edges.
|
|
With this two-step process, internal edges are fully covered when
|
|
antialiasing is applied and there is no corruption on these edges.
|
|
|
|
The key features of this extension are:
|
|
|
|
* It allows render pass and framebuffer objects to be created where the
|
|
number of samples in the depth/stencil attachment in a subpass is a
|
|
multiple of the number of samples in the color attachments in the
|
|
subpass.
|
|
* A coverage reduction step is added to Fragment Operations which converts
|
|
a set of covered raster/depth/stencil samples to a set of color samples
|
|
that perform blending and color writes.
|
|
The coverage reduction step also includes an optional coverage
|
|
modulation step, multiplying color values by a fractional opacity
|
|
corresponding to the number of associated raster/depth/stencil samples
|
|
covered.
|
|
|
|
=== New Object Types
|
|
|
|
None.
|
|
|
|
=== New Enum Constants
|
|
|
|
* Extending elink:VkStructureType
|
|
** ename:VK_STRUCTURE_TYPE_PIPELINE_COVERAGE_MODULATION_STATE_CREATE_INFO_NV
|
|
|
|
=== New Enums
|
|
|
|
* elink:VkCoverageModulationModeNV
|
|
* elink:VkPipelineCoverageModulationStateCreateFlagsNV
|
|
|
|
=== New Structures
|
|
|
|
* slink:VkPipelineCoverageModulationStateCreateInfoNV
|
|
|
|
=== New Functions
|
|
|
|
None.
|
|
|
|
=== Issues
|
|
|
|
None.
|
|
|
|
=== Version History
|
|
|
|
* Revision 1, 2017-06-04 (Jeff Bolz)
|
|
- Internal revisions
|