glAttachShader example c c++ objc java

Name

glAttachShader — Attaches a shader object to a program object

C Specification

void glAttachShader(	GLuint	program,
	GLuint	shader);

Parameters

program

Specifies the program object to which a shader object will be attached.

shader

Specifies the shader object that is to be attached.

Description for glAttachShader

In order to create an executable, there must be a way to specify the list of things that will be linked together. Program objects provide this mechanism. Shaders that are to be linked together in a program object must first be attached to that program object. glAttachShader attaches the shader object specified by shader to the program object specified by program. This indicates that shader will be included in link operations that will be performed on program.
All operations that can be performed on a shader object are valid whether or not the shader object is attached to a program object. It is permissible to attach a shader object to a program object before source code has been loaded into the shader object or before the shader object has been compiled. It is permissible to attach multiple shader objects of the same type because each may contain a portion of the complete shader. It is also permissible to attach a shader object to more than one program object. If a shader object is deleted while it is attached to a program object, it will be flagged for deletion, and deletion will not occur until glDetachShader is called to detach it from all program objects to which it is attached.

Notes

glAttachShader is available only if the GL version is 2.0 or greater.

Errors

GL_INVALID_VALUE is generated if either program or shader is not a value generated by OpenGL.
GL_INVALID_OPERATION is generated if program is not of type GL_PROGRAM_OBJECT.
GL_INVALID_OPERATION is generated if shader is not of type GL_SHADER_OBJECT.
GL_INVALID_OPERATION is generated if shader is already attached to program.
GL_INVALID_OPERATION is generated if glAttachShader is executed between the execution of glBegin and the corresponding execution of glEnd.

Associated Gets

glGetAttachedShaders with the handle of a valid program object
glIsProgram
glIsShader

See Also

glCompileShader, glDetachShader, glLinkProgram, glShaderSource

Copyright

Copyright © 2003-2005 3Dlabs Inc. Ltd. 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/.

Example of glAttachShader

Code collected from GLWiki.

/* The vertex shader */
 char *vsSource = file2string("wave.vert");
 char *fsSource = file2string("wave.frag");
 
 /* Compile and load the program */
 
 GLuint vs, /* Vertex Shader */
     fs, /* Fragment Shader */
     sp; /* Shader Program */
 
 
 vs = glCreateShader(GL_VERTEX_SHADER);
 glShaderSource(vs, 1, &vsSource, NULL);
 glCompileShader(vs);
 printLog(vs);
 
 fs = glCreateShader(GL_FRAGMENT_SHADER);
 glShaderSource(fs, 1, &fsSource, NULL);
 glCompileShader(fs);
 printLog(fs);
 
 free(vsSource);
 free(fsSource);
 
 sp = glCreateProgram();
 glAttachShader(sp, vs);
 glAttachShader(sp, fs);
 glLinkProgram(sp);
 printLog(sp);
 
 glUseProgram(sp);