第一章在VS2008下如何配置好CG环境

第一步：去官网上下载Cg ToolKit并安装

https://developer.nvidia.com/cg-toolkit-download

写此文时，最新版本是

Cg Toolkit 3.1 - April 2012 (3.1.0013)

Windows 32/64-bit
- installer for Windows XP, Vista and Win7.
Mac OS X ppc/i386/x86_64
- dmg for Tiger, Leopard and Snow Leopard.
Linux 32-bit
- tgz tarball
- rpm for RedHat
- deb for Debian and Ubuntu.
Linux 64-bit
- tgz tarball
- rpm for RedHat
- deb for Debian and Ubuntu.

选择适合自己的操作系统，下载好了，就安装吧！

我的安装路径D:\Program Files\NVIDIA Corporation\Cg

第二步：设置路径

1.新建用户变量

变量：CG_HOME

变量值：D:\Program Files\NVIDIA Corporation\Cg

2.在path路径添加：D:\Program Files\NVIDIA Corporation\Cg\bin;

3.VS2008工具－选项－项目和解决方案－VC++目录

包含文件目录添加：$(CG_HOME)\include

库文件目录添加：$(CG_HOME)\lib

第三步：尝试在OPENGL里面使用（因为DX暂时没学。。。）

1.先打开D:\Program Files\NVIDIA Corporation\Cg\examples\OpenGL\basic\01_vertex_program文件夹。你可以看下里面的内容，这就是我们程序所需要的一些文件，这是书上的例子

2.新建－项目(我这里项目名是The_first_Cg_program)，这里选择Win32控制台应用程序

3.项目－属性－配置属性－链接器－输入－附加依赖项，写上cg.lib cgGl.lib

4.新建源文件（我这里源文件名是main.cpp），将先前已打开的文件夹下面的01_vertex_program.c里面文件内容复制到源文件中

5.需要将cg源文件复制到项目目录下，将先前打开的文件夹下面的C2E1v_green.cg复制到你的项目文件夹（我这里是E:\《The Cg Turorial》\chap1\The_first_Cg_program\The_first_Cg_program）。

另外补充说明，其实这样就可以执行了，但是了方便的编辑Cg源文件，这里强烈推荐这样做

找到解决方案资源管理器，右键单击The_first_Cg_program项目，添加－新建筛选器，命名为Cg，右键点击Cg文件夹，添加－现有项，选择刚才拷贝过来的C2E1v_green.cg，这样以后就可以直接在vs2008里面编辑Cg源文件了

6.OK，编译执行。绿色三角形终于出来了，结果如下图：

最后，为了方便那些伸手党，我给main.cpp和C2E1v_green.cg的源码贴上

main.cpp文件

/* 01_vertex_program.c - OpenGL-based very simple vertex program exampleusing Cg program from Chapter 2 of "The Cg Tutorial" (Addison-Wesley,ISBN 0321194969). *//* Requires the OpenGL Utility Toolkit (GLUT) and Cg runtime (version1.0 or higher). */#include <stdio.h>    /* for printf and NULL */
#include <stdlib.h>   /* for exit */
#if __APPLE__
#include <GLUT/glut.h>
#else
#include <GL/glut.h>
#endif
#include <Cg/cg.h>    /* Can't include this?  Is Cg Toolkit installed! */
#include <Cg/cgGL.h>static CGcontext   myCgContext;
static CGprofile   myCgVertexProfile;
static CGprogram   myCgVertexProgram;static const char *myProgramName = "01_vertex_program",*myVertexProgramFileName = "C2E1v_green.cg",
/* Page 38 */     *myVertexProgramName = "C2E1v_green";static void checkForCgError(const char *situation)
{CGerror error;const char *string = cgGetLastErrorString(&error);if (error != CG_NO_ERROR) {printf("%s: %s: %s\n",myProgramName, situation, string);if (error == CG_COMPILER_ERROR) {printf("%s\n", cgGetLastListing(myCgContext));}exit(1);}
}/* Forward declared GLUT callbacks registered by main. */
static void display(void);
static void keyboard(unsigned char c, int x, int y);int main(int argc, char **argv)
{glutInitWindowSize(400, 400);glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);glutInit(&argc, argv);glutCreateWindow(myProgramName);glutDisplayFunc(display);glutKeyboardFunc(keyboard);glClearColor(0.1, 0.3, 0.6, 0.0);  /* Blue background */myCgContext = cgCreateContext();checkForCgError("creating context");cgGLSetDebugMode(CG_FALSE);cgSetParameterSettingMode(myCgContext, CG_DEFERRED_PARAMETER_SETTING);myCgVertexProfile = cgGLGetLatestProfile(CG_GL_VERTEX);cgGLSetOptimalOptions(myCgVertexProfile);checkForCgError("selecting vertex profile");myCgVertexProgram =cgCreateProgramFromFile(myCgContext,              /* Cg runtime context */CG_SOURCE,                /* Program in human-readable form */myVertexProgramFileName,  /* Name of file containing program */myCgVertexProfile,        /* Profile: OpenGL ARB vertex program */myVertexProgramName,      /* Entry function name */NULL);                    /* No extra compiler options */checkForCgError("creating vertex program from file");cgGLLoadProgram(myCgVertexProgram);checkForCgError("loading vertex program");glutMainLoop();return 0;
}static void display(void)
{glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);cgGLBindProgram(myCgVertexProgram);checkForCgError("binding vertex program");cgGLEnableProfile(myCgVertexProfile);checkForCgError("enabling vertex profile");/* Rendering code verbatim from Chapter 1, Section 2.4.1 "Renderinga Triangle with OpenGL" (page 57). */glBegin(GL_TRIANGLES);glVertex2f(-0.8, 0.8);glVertex2f(0.8, 0.8);glVertex2f(0.0, -0.8);glEnd();cgGLDisableProfile(myCgVertexProfile);checkForCgError("disabling vertex profile");glutSwapBuffers();
}static void keyboard(unsigned char c, int x, int y)
{switch (c) {case 27:  /* Esc key *//* Demonstrate proper deallocation of Cg runtime data structures.Not strictly necessary if we are simply going to exit. */cgDestroyProgram(myCgVertexProgram);cgDestroyContext(myCgContext);exit(0);break;}
}

C2E1v_green.cg源码，注意这里只用了顶点着色器

// This is C2E1v_green from "The Cg Tutorial" (Addison-Wesley, ISBN
// 0321194969) by Randima Fernando and Mark J. Kilgard.  See page 38.struct C2E1v_Output {float4 position : POSITION;float3 color    : COLOR;
};C2E1v_Output C2E1v_green(float2 position : POSITION)
{   C2E1v_Output OUT;OUT.position = float4(position,0,1);OUT.color = float3(0,1,0);return OUT;
}