NAME¶
glUseProgram - Installs a program object as part of current rendering state
C SPECIFICATION¶
void
glUseProgram(GLuint program);
PARAMETERS¶
program
Specifies the handle of the program object whose
executables are to be used as part of current rendering state.
DESCRIPTION¶
glUseProgram installs the program object specified by
program as
part of current rendering state. One or more executables are created in a
program object by successfully attaching shader objects to it with
glAttachShader(), successfully compiling the shader objects with
glCompileShader(), and successfully linking the program object with
glLinkProgram().
A program object will contain an executable that will run on the vertex
processor if it contains one or more shader objects of type
GL_VERTEX_SHADER that have been successfully compiled and linked. A
program object will contain an executable that will run on the geometry
processor if it contains one or more shader objects of type
GL_GEOMETRY_SHADER that have been successfully compiled and linked.
Similarly, a program object will contain an executable that will run on the
fragment processor if it contains one or more shader objects of type
GL_FRAGMENT_SHADER that have been successfully compiled and linked.
While a program object is in use, applications are free to modify attached
shader objects, compile attached shader objects, attach additional shader
objects, and detach or delete shader objects. None of these operations will
affect the executables that are part of the current state. However, relinking
the program object that is currently in use will install the program object as
part of the current rendering state if the link operation was successful (see
glLinkProgram() ). If the program object currently in use is relinked
unsuccessfully, its link status will be set to
GL_FALSE, but the
executables and associated state will remain part of the current state until a
subsequent call to
glUseProgram removes it from use. After it is
removed from use, it cannot be made part of current state until it has been
successfully relinked.
If
program is zero, then the current rendering state refers to an
invalid program object and the results of shader execution are
undefined. However, this is not an error.
If
program does not contain shader objects of type
GL_FRAGMENT_SHADER, an executable will be installed on the vertex, and
possibly geometry processors, but the results of fragment shader execution
will be undefined.
NOTES¶
Like buffer and texture objects, the name space for program objects may be
shared across a set of contexts, as long as the server sides of the contexts
share the same address space. If the name space is shared across contexts, any
attached objects and the data associated with those attached objects are
shared as well.
Applications are responsible for providing the synchronization across API calls
when objects are accessed from different execution threads.
ERRORS¶
GL_INVALID_VALUE is generated if
program is neither 0 nor a value
generated by OpenGL.
GL_INVALID_OPERATION is generated if
program is not a program
object.
GL_INVALID_OPERATION is generated if
program could not be made
part of current state.
GL_INVALID_OPERATION is generated if transform feedback mode is active.
ASSOCIATED GETS¶
glGet() with the argument
GL_CURRENT_PROGRAM
glGetActiveAttrib() with a valid program object and the index of an
active attribute variable
glGetActiveUniform() with a valid program object and the index of an
active uniform variable
glGetAttachedShaders() with a valid program object
glGetAttribLocation() with a valid program object and the name of an
attribute variable
glGetProgram() with a valid program object and the parameter to be
queried
glGetProgramInfoLog() with a valid program object
glGetUniform() with a valid program object and the location of a uniform
variable
glGetUniformLocation() with a valid program object and the name of a
uniform variable
glIsProgram()
VERSION SUPPORT¶
|
OpenGL Version |
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Function / Feature Name |
2.0 |
2.1 |
3.0 |
3.1 |
3.2 |
3.3 |
4.0 |
4.1 |
4.2 |
4.3 |
4.4 |
4.5 |
glUseProgram |
✔ |
✔ |
✔ |
✔ |
✔ |
✔ |
✔ |
✔ |
✔ |
✔ |
✔ |
✔ |
SEE ALSO¶
glAttachShader(),
glBindAttribLocation(),
glCompileShader(),
glCreateProgram(),
glDeleteProgram(),
glDetachShader(),
glLinkProgram(),
glUniform(),
glValidateProgram(),
glVertexAttrib()
COPYRIGHT¶
Copyright © 2003-2005 3Dlabs Inc. Ltd. Copyright © 2010-2014
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/.
COPYRIGHT¶
Copyright © 2003-2005 3Dlabs Inc. Ltd.
Copyright © 2010-2014 Khronos Group