GLAPI/glGetActiveUniformBlockName

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glGetActiveUniformBlockName
Core in version 4.4
Core since version 3.1

glGetActiveUniformBlockName: retrieve the name of an active uniform block

Function Definition

 void glGetActiveUniformBlockName(GLuint program​, GLuint uniformBlockIndex​, GLsizei bufSize​, GLsizei *length​, GLchar *uniformBlockName​);
program
Specifies the name of a program containing the uniform block.
uniformBlockIndex
Specifies the index of the uniform block within program​.
bufSize
Specifies the size of the buffer addressed by uniformBlockName​.
length
Specifies the address of a variable to receive the number of characters that were written to uniformBlockName​.
uniformBlockName
Specifies the address an array of characters to receive the name of the uniform block at uniformBlockIndex​.

Description

glGetActiveUniformBlockName retrieves the name of the active uniform block at uniformBlockIndex​ 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.

uniformBlockIndex​ is an active uniform block index of program​, and must be less than the value of GL_ACTIVE_UNIFORM_BLOCKS​.

Upon success, the name of the uniform block identified by unifomBlockIndex​ is returned into uniformBlockName​. The name is nul-terminated. The actual number of characters written into uniformBlockName​, excluding the nul terminator, is returned in length​. If length​ is NULL​, no length is returned.

bufSize​ contains the maximum number of characters (including the nul terminator) that will be written into uniformBlockName​.

If an error occurs, nothing will be written to uniformBlockName​ or length​.

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.

GL_INVALID_VALUE​ is generated if uniformBlockIndex​ is greater than or equal to the value of GL_ACTIVE_UNIFORM_BLOCKS​ or is not the index of an active uniform block in program​.

Notes

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

Associated Gets

glGetProgram with GL_ACTIVE_UNIFORM_BLOCKS​

glGetProgramInterface with GL_UNIFORM_BLOCK​ and GL_ACTIVE_RESOURCES​

glGetUniformBlockIndex

glGetProgramResourceIndex with GL_UNIFORM_BLOCK​

See Also

glGetActiveUniformBlock, glGetProgramResource, glGetProgramResourceName

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/.