2010-2013
Khronos Group
glBindFragDataLocation
3G
glBindFragDataLocation
bind a user-defined varying out variable to a fragment shader color number
C Specification
void glBindFragDataLocation
GLuint program
GLuint colorNumber
const char * name
Parameters
program
The name of the program containing varying out variable whose binding to modify
colorNumber
The color number to bind the user-defined varying out variable to
name
The name of the user-defined varying out variable whose binding to modify
Description
glBindFragDataLocation explicitly specifies the binding of the user-defined varying out variable
name to fragment shader color number colorNumber for program
program. If name was bound previously, its assigned binding is replaced
with colorNumber. name must be a null-terminated string. colorNumber
must be less than GL_MAX_DRAW_BUFFERS.
The bindings specified by glBindFragDataLocation have no effect until program
is next linked. Bindings may be specified at any time after program has been created. Specifically,
they may be specified before shader objects are attached to the program. Therefore, any name may be specified in name,
including a name that is never used as a varying out variable in any fragment shader object. Names beginning with gl_ are
reserved by the GL.
In addition to the errors generated by glBindFragDataLocation, the
program program will fail to link if:
The number of active outputs is greater than the value GL_MAX_DRAW_BUFFERS.
More than one varying out variable is bound to the same color number.
Notes
Varying out varyings may have indexed locations assigned explicitly in the shader text using a location
layout qualifier. If a shader statically assigns a location to a varying out variable in the shader text,
that location is used and any location assigned with glBindFragDataLocation is ignored.
Errors
GL_INVALID_VALUE is generated if colorNumber is greater than or equal to GL_MAX_DRAW_BUFFERS.
GL_INVALID_OPERATION is generated if name starts with the reserved gl_ prefix.
GL_INVALID_OPERATION is generated if program is not the name of a program object.
Associated Gets
glGetFragDataLocation with a valid program object
and the the name of a user-defined varying out variable
See Also
glCreateProgram,
glGetFragDataLocation
Copyright
Copyright 2010-2013 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/.