Safe Haskell | Safe-Inferred |
---|---|
Language | Haskell2010 |
Name
VK_EXT_primitives_generated_query - device extension
VK_EXT_primitives_generated_query
- Name String
VK_EXT_primitives_generated_query
- Extension Type
- Device extension
- Registered Extension Number
- 383
- Revision
- 1
- Ratification Status
- Not ratified
- Extension and Version Dependencies
- VK_EXT_transform_feedback
- Special Use
- Contact
- Extension Proposal
- VK_EXT_primitives_generated_query
Other Extension Metadata
- Last Modified Date
- 2022-01-24
- Contributors
- Shahbaz Youssefi, Google
- Piers Daniell, NVIDIA
- Faith Ekstrand, Collabora
- Jan-Harald Fredriksen, Arm
Description
This extension adds support for a new query type to match OpenGL’s
GL_PRIMITIVES_GENERATED
to support layering.
New Structures
Extending
PhysicalDeviceFeatures2
,DeviceCreateInfo
:
New Enum Constants
EXT_PRIMITIVES_GENERATED_QUERY_SPEC_VERSION
Extending
QueryType
:Extending
StructureType
:
Issues
1) Can the query from VK_EXT_transform_feedback
be used instead?
RESOLVED: No. While the query from VK_EXT_transform_feedback can
produce the same results as in this extension, it is only available
while transform feedback is active. The OpenGL GL_PRIMITIVES_GENERATED
query is independent from transform feedback. Emulation through
artificial transform feedback is unnecessarily inefficient.
2) Can
QUERY_PIPELINE_STATISTIC_CLIPPING_INVOCATIONS_BIT
be used instead?
RESOLVED: It could, but we prefer the extension for simplicity.
Vulkan requires that only one query be active at a time. If both the
GL_PRIMITIVES_GENERATED
and the GL_CLIPPING_INPUT_PRIMITIVES_ARB
queries need to be simultaneously enabled, emulation of both through
QUERY_PIPELINE_STATISTIC_CLIPPING_INVOCATIONS_BIT
is inconvenient.
3) On some hardware, this query cannot be implemented if
PipelineRasterizationStateCreateInfo
::rasterizerDiscardEnable
is enabled. How will this be handled?
RESOLVED: A feature flag is exposed by this extension for this. On said hardware, the GL implementation disables rasterizer-discard and achieves the same effect through other means. It will not be able to do the same in Vulkan due to lack of state information. A feature flag is exposed by this extension so the OpenGL implementation on top of Vulkan would be able to implement a similar workaround.
4) On some hardware, this query cannot be implemented for non-zero query indices. How will this be handled?
RESOLVED: A feature flag is exposed by this extension for this. If
this feature is not present, the query from VK_EXT_transform_feedback
can be used to the same effect.
5) How is the interaction of this extension with
transformFeedbackRasterizationStreamSelect
handled?
RESOLVED: Disallowed for non-zero streams. In OpenGL, the rasterization stream is always stream zero.
Version History
Revision 1, 2021-06-23 (Shahbaz Youssefi)
- Internal revisions
See Also
PhysicalDevicePrimitivesGeneratedQueryFeaturesEXT
Document Notes
For more information, see the Vulkan Specification
This page is a generated document. Fixes and changes should be made to the generator scripts, not directly.
Synopsis
- data PhysicalDevicePrimitivesGeneratedQueryFeaturesEXT = PhysicalDevicePrimitivesGeneratedQueryFeaturesEXT {}
- type EXT_PRIMITIVES_GENERATED_QUERY_SPEC_VERSION = 1
- pattern EXT_PRIMITIVES_GENERATED_QUERY_SPEC_VERSION :: forall a. Integral a => a
- type EXT_PRIMITIVES_GENERATED_QUERY_EXTENSION_NAME = "VK_EXT_primitives_generated_query"
- pattern EXT_PRIMITIVES_GENERATED_QUERY_EXTENSION_NAME :: forall a. (Eq a, IsString a) => a
Documentation
data PhysicalDevicePrimitivesGeneratedQueryFeaturesEXT Source #
VkPhysicalDevicePrimitivesGeneratedQueryFeaturesEXT - Structure describing support for primitives generated query
Members
This structure describes the following features:
Description
If the PhysicalDevicePrimitivesGeneratedQueryFeaturesEXT
structure is
included in the pNext
chain of the
PhysicalDeviceFeatures2
structure passed to
getPhysicalDeviceFeatures2
,
it is filled in to indicate whether each corresponding feature is
supported. PhysicalDevicePrimitivesGeneratedQueryFeaturesEXT
can
also be used in the pNext
chain of
DeviceCreateInfo
to selectively enable these
features.
Valid Usage (Implicit)
See Also
PhysicalDevicePrimitivesGeneratedQueryFeaturesEXT | |
|
Instances
pattern EXT_PRIMITIVES_GENERATED_QUERY_SPEC_VERSION :: forall a. Integral a => a Source #
type EXT_PRIMITIVES_GENERATED_QUERY_EXTENSION_NAME = "VK_EXT_primitives_generated_query" Source #
pattern EXT_PRIMITIVES_GENERATED_QUERY_EXTENSION_NAME :: forall a. (Eq a, IsString a) => a Source #