概述
   
    不同平台OpenGL开发环境的配置大同小异,我认为可以分为4部分:
    
    1. OpenGL库:Mac OS X、Windows已经预安装,可以直接使用,linux和unix则需要自己安装,安装方法自行Google,在此不做详解。
    
    2. OpenGL扩展库:GLEW提供了高效的运行机制,来决定哪个OpenGL扩展在目标平台上是否支持。它将OpenGL核心和扩展功能暴露在一个头文件,以供使用。安装方法自行Google,在此不做详解。
    
    3. 应用程序框架:OpenGL是一种应用程序编程接口,本身不具有创建窗口、接收外设事件等功能,所以需要第三方软件库。目前应用较广泛的有GLUT和GLFW等,安装方法自行Google,在此不做详解。
    
    4. 其他实用工具库:
   
    Mac OS X平台通用步骤:
   
- 链接GLUT.framwork和OpenGL.framwork库。
- 导入GLEW扩展库。
    基于xcode7的示例:
   
- 
     链接GLUT.framwork和OpenGL.framwork库。
 
 
- 
     导入GLEW扩展库。
 
 
 
 
- 基本配置已经完成,引用OpenGL编程指南(第8版)的triangles实例,来展示一个OpenGL应用的基本结构。
triangles.cpp
#include <stdio.h>
#include <iostream>
#include <gl/glew.h>
#include <GLUT/GLUT.h>
#include "LoadShaders.h"
#define BUFFER_OFFSET(x)  ((const void*) (x))
enum VAO_IDs { Triangles, NumVAOs };
enum Buffer_IDs { ArrayBuffer, NumBuffers };
enum Attrib_IDs { vPosition = 0 };
GLuint VAOs[NumVAOs];
GLuint Buffers[NumBuffers];
const GLuint NumVertices = 6;
void init(void)
{
    glGenVertexArrays(NumVAOs, VAOs);
    glBindVertexArray(VAOs[Triangles]);
    GLfloat vertices[NumVertices][2] = {
        { -0.90, -0.90 },
        {  0.85, -0.90 },
        { -0.90,  0.85 },
        {  0.90, -0.85 },
        {  0.90,  0.90 },
        { -0.85,  0.90 }
    };
    glGenBuffers(NumBuffers, Buffers);
    glBindBuffer(GL_ARRAY_BUFFER, Buffers[ArrayBuffer]);
    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
    ShaderInfo shaders[] = {
        { GL_VERTEX_SHADER, "/Users/LXY/Desktop/test_opengl/triangles.vert" },
        { GL_FRAGMENT_SHADER, "/Users/LXY/Desktop/test_opengl/triangles.frag" },
        { GL_NONE, NULL }
    };
    GLuint program = LoadShaders(shaders);
    glUseProgram(program);
    glVertexAttribPointer(vPosition, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
    glEnableVertexAttribArray(vPosition);
}
void display(void)
{
    glClear(GL_COLOR_BUFFER_BIT);
    glBindVertexArray(VAOs[Triangles]);
    glDrawArrays(GL_TRIANGLES, 0, NumVertices);
    glFlush();
}
int main(int argc, const char * argv[])
{
    glutInit(&argc, (char**)argv);
    glutInitDisplayMode(GLUT_3_2_CORE_PROFILE | GLUT_RGBA);
    glutInitWindowSize(512, 512);
    glutCreateWindow(argv[0]);
    glewExperimental = GL_TRUE;
    GLenum err = glewInit();
    if (GLEW_OK != err) {
        fprintf(stderr, "Error: %s\n", glewGetErrorString(err));
    }
    fprintf(stdout, "Status: Using GLEW %s\n", glewGetString(GLEW_VERSION));
    if (GLEW_VERSION_4_1) {
        std::cout << "Yay! OpenGL 4.1 is supported!" << std::endl;
    }
    init();
    glutDisplayFunc(display);
    glutMainLoop();
}
}LoadShaders.h
//////////////////////////////////////////////////////////////////////////////
//
//  --- LoadShaders.h ---
//
//////////////////////////////////////////////////////////////////////////////
#ifndef __LOAD_SHADERS_H__
#define __LOAD_SHADERS_H__
#include <OpenGL/OpenGL.h>
#ifdef __cplusplus
extern "C" {
#endif  // __cplusplus
//----------------------------------------------------------------------------
//
//  LoadShaders() takes an array of ShaderFile structures, each of which
//    contains the type of the shader, and a pointer a C-style character
//    string (i.e., a NULL-terminated array of characters) containing the
//    entire shader source.
//
//  The array of structures is terminated by a final Shader with the
//    "type" field set to GL_NONE.
//
//  LoadShaders() returns the shader program value (as returned by
//    glCreateProgram()) on success, or zero on failure. 
//
typedef struct {
    GLenum       type;
    const char*  filename;
    GLuint       shader;
} ShaderInfo;
GLuint LoadShaders( ShaderInfo* );
//----------------------------------------------------------------------------
#ifdef __cplusplus
};
#endif // __cplusplus
#endif // __LOAD_SHADERS_H__
LoadShaders.cpp
//////////////////////////////////////////////////////////////////////////////
//
//  --- LoadShaders.cxx ---
//
//////////////////////////////////////////////////////////////////////////////
#include <cstdlib>
#include <iostream>
#define GLEW_STATIC
#include <GL/glew.h>
#include "LoadShaders.h"
#ifdef __cplusplus
extern "C" {
#endif // __cplusplus
//----------------------------------------------------------------------------
static const GLchar*
ReadShader( const char* filename )
{
#ifdef WIN32
    FILE* infile;
    fopen_s( &infile, filename, "rb" );
#else
    FILE* infile = fopen( filename, "rb" );
#endif // WIN32
    if ( !infile ) {
#ifdef _DEBUG
        std::cerr << "Unable to open file '" << filename << "'" << std::endl;
#endif /* DEBUG */
        return NULL;
    }
    fseek( infile, 0, SEEK_END );
    int len = ftell( infile );
    fseek( infile, 0, SEEK_SET );
    GLchar* source = new GLchar[len+1];
    fread( source, 1, len, infile );
    fclose( infile );
    source[len] = 0;
    return const_cast<const GLchar*>(source);
}
//----------------------------------------------------------------------------
GLuint
LoadShaders( ShaderInfo* shaders )
{
    if ( shaders == NULL ) { return 0; }
    GLuint program = glCreateProgram();
    ShaderInfo* entry = shaders;
    while ( entry->type != GL_NONE ) {
        GLuint shader = glCreateShader( entry->type );
        entry->shader = shader;
        const GLchar* source = ReadShader( entry->filename );
        if ( source == NULL ) {
            for ( entry = shaders; entry->type != GL_NONE; ++entry ) {
                glDeleteShader( entry->shader );
                entry->shader = 0;
            }
            return 0;
        }
        glShaderSource( shader, 1, &source, NULL );
        delete [] source;
        glCompileShader( shader );
        GLint compiled;
        glGetShaderiv( shader, GL_COMPILE_STATUS, &compiled );
        if ( !compiled ) {
#ifdef _DEBUG
            GLsizei len;
            glGetShaderiv( shader, GL_INFO_LOG_LENGTH, &len );
            GLchar* log = new GLchar[len+1];
            glGetShaderInfoLog( shader, len, &len, log );
            std::cerr << "Shader compilation failed: " << log << std::endl;
            delete [] log;
#endif /* DEBUG */
            return 0;
        }
        glAttachShader( program, shader );
        ++entry;
    }
#ifdef GL_VERSION_4_1
    if ( GLEW_VERSION_4_1 ) {
        // glProgramParameteri( program, GL_PROGRAM_SEPARABLE, GL_TRUE );
    }
#endif /* GL_VERSION_4_1 */
    glLinkProgram( program );
    GLint linked;
    glGetProgramiv( program, GL_LINK_STATUS, &linked );
    if ( !linked ) {
#ifdef _DEBUG
        GLsizei len;
        glGetProgramiv( program, GL_INFO_LOG_LENGTH, &len );
        GLchar* log = new GLchar[len+1];
        glGetProgramInfoLog( program, len, &len, log );
        std::cerr << "Shader linking failed: " << log << std::endl;
        delete [] log;
#endif /* DEBUG */
        for ( entry = shaders; entry->type != GL_NONE; ++entry ) {
            glDeleteShader( entry->shader );
            entry->shader = 0;
        }
        return 0;
    }
    return program;
}
//----------------------------------------------------------------------------
#ifdef __cplusplus
}
#endif // __cplusplus
    result:
    
    
   
 
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