GLAPI/glGetUniformIndices

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glGetUniformIndices
Core in version 4.4
Core since version 3.1

glGetUniformIndices: retrieve the index of a named uniform block

Function Definition

 void glGetUniformIndices(GLuint program​, GLsizei uniformCount​, const GLchar **uniformNames​, GLuint *uniformIndices​);
program
Specifies the name of a program containing uniforms whose indices to query.
uniformCount
Specifies the number of uniforms whose indices to query.
uniformNames
Specifies the address of an array of pointers to buffers containing the names of the queried uniforms.
uniformIndices
Specifies the address of an array that will receive the indices of the uniforms.

Description

glGetUniformIndices retrieves the indices of a number of uniforms within program​.

program​ must be the name of a program object for which the command glLinkProgram must have been called in the past, although it is not required that glLinkProgram must have succeeded. The link could have failed because the number of active uniforms exceeded the limit.

uniformCount​ indicates both the number of elements in the array of names uniformNames​ and the number of indices that may be written to uniformIndices​.

uniformNames​ contains a list of uniformCount​ name strings identifying the uniform names to be queried for indices. For each name string in uniformNames​, the index assigned to the active uniform of that name will be written to the corresponding element of uniformIndices​. If a string in uniformNames​ is not the name of an active uniform, the special value GL_INVALID_INDEX​ will be written to the corresponding element of uniformIndices​.

If an error occurs, nothing is written to uniformIndices​.

Errors

GL_INVALID_OPERATION​ is generated if program​ is not the name of a program object for which glLinkProgram has been called in the past.

Notes

glGetUniformIndices is available only if the GL version is 3.1 or greater.

See Also

glGetActiveUniform, glGetActiveUniformName, glGetProgramResourceIndex

Copyright

Copyright © 2010 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/.