glBindFragDataLocation — bind a user-defined varying out variable to a fragment shader color number
void glBindFragDataLocation( | GLuint | program, |
GLuint | colorNumber, | |
const char * | name) ; |
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
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.
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.
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.
glGetFragDataLocation with a valid program object and the the name of a user-defined varying out variable
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/.