glGetUniformBlockIndex - retrieve the index of a named uniform block

GLuintglGetUniformBlockIndex(GLuintprogram,constGLchar*uniformBlockName);

       Copyright © 2010-2014 Khronos Group

[FIXME: source]                                    11/18/2024                           GLGETUNIFORMBLOCKIND(3G)

glGetUniformBlockIndex retrieves the index of a uniform block 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.

       uniformBlockName must contain a nul-terminated string specifying the name of the uniform block.

       glGetUniformBlockIndex returns the uniform block index for the uniform block named uniformBlockName of
       program. If uniformBlockName does not identify an active uniform block of program, glGetUniformBlockIndex
       returns the special identifier, GL_INVALID_INDEX. Indices of the active uniform blocks of a program are
       assigned in consecutive order, beginning with zero.

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

       glGetUniformBlockIndex - retrieve the index of a named uniform block

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

program
           Specifies the name of a program containing the uniform block.

       uniformBlockName
           Specifies the address an array of characters to containing the name of the uniform block whose index
           to retrieve.

glGetActiveUniformBlockName(), glGetActiveUniformBlock(), glLinkProgram()

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       ├────────────────────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │ glGetUniformBlockIndex │  -  │  -  │  -  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
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