gl_GlobalInvocationID - OpenGL 4 Reference Pages

## Name

gl_GlobalInvocationID — contains the global index of work item currently being operated on by a compute shader

## Declaration

`in uvec3 gl_GlobalInvocationID ;`

## Description

In the compute language, `gl_GlobalInvocationID` is a derived input variable containing the n-dimensional index of the work invocation within the global work group that the current shader is executing on. The value of `gl_GlobalInvocationID` is equal to `gl_WorkGroupID` * `gl_WorkGroupSize` + `gl_LocalInvocationID`.

## Version Support

| OpenGL Shading Language Version
--- | ---
Variable Name | 1.10 | 1.20 | 1.30 | 1.40 | 1.50 | 3.30 | 4.00 | 4.10 | 4.20 | 4.30 | 4.40 | 4.50
gl_GlobalInvocationID | - | - | - | - | - | - | - | - | - | ✔ | ✔ | ✔

## See Also

gl_NumWorkGroups, gl_WorkGroupID, gl_WorkGroupSize, gl_LocalInvocationID

## 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/.