Class NVXMultiviewPerViewAttributes


  • public final class NVXMultiviewPerViewAttributes
    extends java.lang.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 vertex processing 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 vertex processing 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 VK_NV_viewport_array2 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
    Contact
    Last Modified Date
    2017-01-13
    IP Status
    No known IP claims.
    Interactions and External Dependencies
    Contributors
    • Jeff Bolz, NVIDIA
    • Daniel Koch, NVIDIA