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NAME
gl_InvocationID - contains the invocation index of the current shader
DECLARATION
in int gl_InvocationID ;.SH "DESCRIPTION"
In the tessellation control language, gl_InvocationID contains the index of the output patch vertex
assigned to the shader invocation. It is assigned an integer value in the range [0, N-1] where N is the
number of output patch vertices.
In the geometry language, gl_InvocationID identifies the invocation number assigned to the geometry
shader invocation. It is assigned an integer value in the range [0, N-1] where N is the number of
geometry shader invocations per primitive.
VERSION SUPPORT
┌─────────────────┬───────────────────────────────────────────────────────────────────────────────────┐
│ │ OpenGL Shading Language Version │
├─────────────────┼──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┤
│ Variable │ 1.10 │ 1.20 │ 1.30 │ 1.40 │ 1.50 │ 3.30 │ 4.00 │ 4.10 │ 4.20 │ 4.30 │ 4.40 │ 4.50 │
│ Name │ │ │ │ │ │ │ │ │ │ │ │ │
├─────────────────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┤
│ gl_InvocationID │ - │ - │ - │ - │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │
└─────────────────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┘
[1] Versions 1.50 to 3.30 - geometry shaders only.
SEE ALSO
gl_InstanceID()
COPYRIGHT
Copyright © 2011-2014 Khronos Group. This material may be distributed subject to the terms and conditions
set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.
COPYRIGHT
Copyright © 2011-2014 Khronos Group
[FIXME: source] 01/03/2018 GL_INVOCATIONID(3G)