2010 Khronos Group.
glGetUniformSubroutine 3G
glGetUniformSubroutine retrieve the value of a subroutine uniform of a given shader stage of the current program

## C Specification

void `glGetUniformSubroutineuiv` GLenum shadertype GLint location GLuint *values

## Parameters

shadertype

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

location

  Specifies the location of the subroutine uniform.

values

  Specifies the address of a variable to receive the value or values of the subroutine uniform.

## Description

`glGetUniformSubroutine` retrieves the value of the subroutine uniform at location location for shader stage shadertype of the current program. location must be less than the value of `GL_ACTIVE_SUBROUTINE_UNIFORM_LOCATIONS` for the shader currently in use at shader stage shadertype. The value of the subroutine uniform is returned in values.

## Errors

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

`GL_INVALID_VALUE` is generated if location is greater than or equal to the value of `GL_ACTIVE_SUBROUTINE_UNIFORM_LOCATIONS` for the shader currently in use at shader stage shadertype.

`GL_INVALID_OPERATION` is generated if no program is active.

## See Also

glGetProgram, glGetActiveSubroutineUniform, glGetActiveSubroutineUniformName, glGetUniformLocation

## 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/.