glGetFragDataIndex - query the bindings of color indices to user-defined varying out variables

GLintglGetFragDataIndex(GLuintprogram,constchar*name);

       Copyright © 2010-2014 Khronos Group

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

glGetFragDataIndex returns the index of the fragment color to which the variable name was bound when the
       program object program was last linked. If name is not a varying out variable of program, or if an error
       occurs, -1 will be returned.

GL_INVALID_OPERATION is generated if program is not the name of a program object.

       glGetFragDataIndex - query the bindings of color indices to user-defined varying out variables

glGetFragDataIndex is available only if the GL version is 3.3 or greater.

program
           The name of the program containing varying out variable whose binding to query

       name
           The name of the user-defined varying out variable whose index to query

glCreateProgram(), glBindFragDataLocation(), glBindFragDataLocationIndexed(), glGetFragDataLocation()

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       │                    │                OpenGLVersion                                         │
       ├────────────────────┼─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┤
       │ Function           │ 2.0 │ 2.1 │ 3.0 │ 3.1 │ 3.2 │ 3.3 │ 4.0 │ 4.1 │ 4.2 │ 4.3 │ 4.4 │ 4.5 │
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       │ Feature            │     │     │     │     │     │     │     │     │     │     │     │     │
       │ Name               │     │     │     │     │     │     │     │     │     │     │     │     │
       ├────────────────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │ glGetFragDataIndex │  -  │  -  │  -  │  -  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
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