[[VK_NV_external_memory]] == VK_NV_external_memory *Name String*:: +VK_NV_external_memory+ *Extension Type*:: Device extension *Registered Extension Number*:: 57 *Status*:: Complete *Last Modified Date*:: 2016-08-19 *Revision*:: 1 *IP Status*:: No known IP claims. *Dependencies*:: - This extension is written against version 1.0 of the Vulkan API. - Requires +VK_NV_external_memory_capabilities+. *Contributors*:: - James Jones, NVIDIA - Carsten Rohde, NVIDIA *Contact*:: - James Jones (jajones 'at' nvidia.com) Applications may wish to export memory to other Vulkan instances or other APIs, or import memory from other Vulkan instances or other APIs to enable Vulkan workloads to be split up across application module, process, or API boundaries. This extension enables applications to create exportable Vulkan memory objects such that the underlying resources can be referenced outside the Vulkan instance that created them. === New Object Types None. === New Enum Constants Extending elink:VkStructureType: ** ename:VK_STRUCTURE_TYPE_EXTERNAL_MEMORY_IMAGE_CREATE_INFO_NV ** ename:VK_STRUCTURE_TYPE_EXPORT_MEMORY_ALLOCATE_INFO_NV === New Enums None. === New Structures * Extending slink:VkImageCreateInfo: ** slink:VkExternalMemoryImageCreateInfoNV * Extending slink:VkMemoryAllocateInfo ** slink:VkExportMemoryAllocateInfoNV === New Functions None. === Issues 1) If memory objects are shared between processes and APIs, is this considered aliasing according to the rules outlined in the <> section? *RESOLVED*: Yes, but strict exceptions to the rules are added to allow some forms of aliasing in these cases. Further, other extensions may build upon these new aliasing rules to define specific support usage within Vulkan for imported native memory objects, or memory objects from other APIs. 2) Are new image layouts or metadata required to specify image layouts and layout transitions compatible with non-Vulkan APIs, or with other instances of the same Vulkan driver? *RESOLVED*: No. Separate instances of the same Vulkan driver running on the same GPU should have identical internal layout semantics, so applictions have the tools they need to ensure views of images are consistent between the two instances. Other APIs will fall into two categories: Those that are Vulkan compatible (A term to be defined by subsequent interopability extensions), or Vulkan incompatible. When sharing images with Vulkan incompatible APIs, the Vulkan image must be transitioned to the GENERAL layout before handing it off to the external API. Note this does not attempt to address cross-device transitions, nor transitions to engines on the same device which are not visible within the Vulkan API. Both of these are beyond the scope of this extension. === Examples [source,c++] ---------------------------------------- // TODO: Write some sample code here. ---------------------------------------- === Version History * Revision 1, 2016-08-19 (James Jones) - Initial draft