NAME

       glGetActiveSubroutineUniformName - query the name of an active shader subroutine uniform

C SPECIFICATION

       void glGetActiveSubroutineUniformName(GLuint program, GLenum shadertype, GLuint index,
                                             GLsizei bufsize, GLsizei *length, GLchar *name);

PARAMETERS

       program
           Specifies the name of the program containing the subroutine.

       shadertype
           Specifies the shader stage from which to query for the subroutine parameter.
           shadertype must be one of GL_VERTEX_SHADER, GL_TESS_CONTROL_SHADER,
           GL_TESS_EVALUATION_SHADER, GL_GEOMETRY_SHADER or GL_FRAGMENT_SHADER.

       index
           Specifies the index of the shader subroutine uniform.

       bufsize
           Specifies the size of the buffer whose address is given in name.

       length
           Specifies the address of a variable into which is written the number of characters
           copied into name.

       name
           Specifies the address of a buffer that will receive the name of the specified shader
           subroutine uniform.

DESCRIPTION

       glGetActiveSubroutineUniformName retrieves the name of an active shader subroutine
       uniform.  program contains the name of the program containing the uniform.  shadertype
       specifies the stage for which which the uniform location, given by index, is valid.  index
       must be between zero and the value of GL_ACTIVE_SUBROUTINE_UNIFORMS minus one for the
       shader stage.

       The uniform name is returned as a null-terminated string in name. The actual number of
       characters written into name, excluding the null terminator is returned in length. If
       length is NULL, no length is returned. The maximum number of characters that may be
       written into name, including the null terminator, is specified by bufsize. The length of
       the longest subroutine uniform name in program and shadertype is given by the value of
       GL_ACTIVE_SUBROUTINE_UNIFORM_MAX_LENGTH, which can be queried with glGetProgramStage().

ERRORS

       GL_INVALID_ENUM is generated if shadertype or pname is not one of the accepted values.

       GL_INVALID_VALUE is generated if index is greater than or equal to the value of
       GL_ACTIVE_SUBROUTINES.

       GL_INVALID_VALUE is generated if program is not the name of an existing program object.

ASSOCIATED GETS

       glGetProgramStage() with argument GL_ACTIVE_SUBROUTINE_UNIFORMS

SEE ALSO

       glGetSubroutineIndex(), glGetActiveSubroutineUniform(), glGetProgramStage()

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/.

AUTHORS

       opengl.org