Package org.lwjgl.vulkan

Class NVXMultiviewPerViewAttributes

java.lang.Object
org.lwjgl.vulkan.NVXMultiviewPerViewAttributes
public final class NVXMultiviewPerViewAttributes extends Object
This extension adds a new way to write shaders to be used with multiview subpasses, where the attributes for all views are written out by a single invocation of the pre-rasterization shader stages. Related SPIR-V and GLSL extensions SPV_NVX_multiview_per_view_attributes and GL_NVX_multiview_per_view_attributes introduce per-view position and viewport mask attributes arrays, and this extension defines how those per-view attribute arrays are interpreted by Vulkan. Pipelines using per-view attributes may only execute the pre-rasterization shader stages once for all views rather than once per-view, which reduces redundant shading work.

A subpass creation flag controls whether the subpass uses this extension. A subpass must either exclusively use this extension or not use it at all.

Some Vulkan implementations only support the position attribute varying between views in the X component. A subpass can declare via a second creation flag whether all pipelines compiled for this subpass will obey this restriction.

Shaders that use the new per-view outputs (e.g. gl_PositionPerViewNV) must also write the non-per-view output (gl_Position), and the values written must be such that gl_Position = gl_PositionPerViewNV[gl_ViewIndex] for all views in the subpass. Implementations are free to either use the per-view outputs or the non-per-view outputs, whichever would be more efficient.

If the VK_NV_viewport_array2 extension is not also supported and enabled, the per-view viewport mask must not be used.

Examples

 #version 450 core
 
 #extension GL_KHX_multiview : enable
 #extension GL_NVX_multiview_per_view_attributes : enable
 
 layout(location = 0) in vec4 position;
 layout(set = 0, binding = 0) uniform Block { mat4 mvpPerView[2]; } buf;
 
 void main()
 {
     // Output both per-view positions and gl_Position as a function
     // of gl_ViewIndex
     gl_PositionPerViewNV[0] = buf.mvpPerView[0] * position;
     gl_PositionPerViewNV[1] = buf.mvpPerView[1] * position;
     gl_Position = buf.mvpPerView[gl_ViewIndex] * position;
 }
Name String
VK_NVX_multiview_per_view_attributes
Extension Type
Device extension
Registered Extension Number
98
Revision
1
Extension and Version Dependencies
VK_KHR_multiview or Version 1.1
API Interactions
  • Interacts with VK_VERSION_1_3
  • Interacts with VK_KHR_dynamic_rendering
SPIR-V Dependencies
Contact
Other Extension Metadata
Last Modified Date
2017-01-13
IP Status
No known IP claims.
Interactions and External Dependencies
Contributors
  • Jeff Bolz, NVIDIA
  • Daniel Koch, NVIDIA