glShaderSource example c c++ java objc

Name

glShaderSource — Replaces the source code in a shader object

C Specification

void glShaderSource(	GLuint	shader,
	GLsizei	count,
	const GLchar **	string,
	const GLint *	length);

Parameters

shader

Specifies the handle of the shader object whose source code is to be replaced.

count

Specifies the number of elements in the string and length arrays.

string

Specifies an array of pointers to strings containing the source code to be loaded into the shader.

length

Specifies an array of string lengths.

Description

glShaderSource sets the source code in shader to the source code in the array of strings specified by string. Any source code previously stored in the shader object is completely replaced. The number of strings in the array is specified by count. If length is NULL, each string is assumed to be null terminated. If length is a value other than NULL, it points to an array containing a string length for each of the corresponding elements of string. Each element in the length array may contain the length of the corresponding string (the null character is not counted as part of the string length) or a value less than 0 to indicate that the string is null terminated. The source code strings are not scanned or parsed at this time; they are simply copied into the specified shader object.

Notes

glShaderSource is available only if the GL version is 2.0 or greater.
OpenGL copies the shader source code strings when glShaderSource is called, so an application may free its copy of the source code strings immediately after the function returns.

Errors

GL_INVALID_VALUE is generated if shader is not a value generated by OpenGL.
GL_INVALID_OPERATION is generated if shader is not a shader object.
GL_INVALID_VALUE is generated if count is less than 0.
GL_INVALID_OPERATION is generated if glShaderSource is executed between the execution of glBegin and the corresponding execution of glEnd.

Associated Gets

glGetShader with arguments shader and GL_SHADER_SOURCE_LENGTH
glGetShaderSource with argument shader
glIsShader

See Also

glCompileShader, glCreateShader, glDeleteShader

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 glShaderSource

/* 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);