Friday, April 19, 2013

GL_FRAGMENT_SHADER example c c++ java objc


GL_FRAGMENT_SHADER description.

Name

glCreateShader — Creates a shader object

C Specification

GLuint glCreateShader(GLenum shaderType);

Parameters

shaderType
Specifies the type of shader to be created. Must be one of GL_VERTEX_SHADERGL_TESS_CONTROL_SHADERGL_TESS_EVALUATION_SHADERGL_GEOMETRY_SHADER, or GL_FRAGMENT_SHADER.

Description

(GL_FRAGMENT_SHADER)glCreateShader creates an empty shader object and returns a non-zero value by which it can be referenced. A shader object is used to maintain the source code strings that define a shader. shaderType indicates the type of shader to be created. Five types of shader are supported. A shader of type GL_VERTEX_SHADER is a shader that is intended to run on the programmable vertex processor. A shader of type GL_TESS_CONTROL_SHADER is a shader that is intended to run on the programmable tessellation processor in the control stage. A shader of type GL_TESS_EVALUATION_SHADER is a shader that is intended to run on the programmable tessellation processor in the evaluation stage. A shader of type GL_GEOMETRY_SHADER is a shader that is intended to run on the programmable geometry processor. A shader of type GL_FRAGMENT_SHADER is a shader that is intended to run on the programmable fragment processor.
When created, a shader object's GL_SHADER_TYPE parameter is set to either GL_VERTEX_SHADERGL_TESS_CONTROL_SHADERGL_TESS_EVALUATION_SHADERGL_GEOMETRY_SHADER or GL_FRAGMENT_SHADER, depending on the value of shaderType.

Notes

Like buffer and texture objects, the name space for shader 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

This function returns 0 if an error occurs creating the shader object.
GL_INVALID_ENUM is generated if shaderType is not an accepted value.

Associated Gets

glGetShader with a valid shader object and the parameter to be queried
glGetShaderInfoLog with a valid shader object
glGetShaderSource with a valid shader object
glIsShader

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


{
/* 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);
 }