Description

ClipDistance

Decorating a variable with the ClipDistance built-in decoration will make that variable contain the mechanism for controlling user clipping. ClipDistance is an array such that the ith element of the array specifies the clip distance for plane i. A clip distance of 0 means the vertex is on the plane, a positive distance means the vertex is inside the clip half-space, and a negative distance means the vertex is outside the clip half-space.

Note

The array variable decorated with ClipDistance is explicitly sized by the shader.
Note

In the last pre-rasterization shader stage, these values will be linearly interpolated across the primitive and the portion of the primitive with interpolated distances less than 0 will be considered outside the clip volume. If ClipDistance is then used by a fragment shader, ClipDistance contains these linearly interpolated values.
Valid Usage

  • VUID-ClipDistance-ClipDistance-04187
    The ClipDistance decoration must be used only within the MeshEXT, MeshNV, Vertex, Fragment, TessellationControl, TessellationEvaluation, or Geometry Execution Model

  • VUID-ClipDistance-ClipDistance-04188
    The variable decorated with ClipDistance within the MeshEXT, MeshNV, or Vertex Execution Model must be declared using the Output Storage Class

  • VUID-ClipDistance-ClipDistance-04189
    The variable decorated with ClipDistance within the Fragment Execution Model must be declared using the Input Storage Class

  • VUID-ClipDistance-ClipDistance-04190
    The variable decorated with ClipDistance within the TessellationControl, TessellationEvaluation, or Geometry Execution Model must not be declared in a Storage Class other than Input or Output

  • VUID-ClipDistance-ClipDistance-04191
    The variable decorated with ClipDistance must be declared as an array of 32-bit floating-point values

See Also

No cross-references are available

Document Notes

For more information, see the Vulkan Specification

This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification, not directly.

Copyright

Copyright 2014-2024 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0