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案例在前一个基础上将计算过程放到了片段着色器，来增强细节处理。

// ADS Point lighting Shader// Vertex Shader// Richard S. Wright Jr.// OpenGL SuperBible#version 130// Incoming per vertex... position and normalin vec4 vVertex;in vec3 vNormal;uniform mat4   mvpMatrix;uniform mat4   mvMatrix;uniform mat3   normalMatrix;uniform vec3   vLightPosition;// Color to fragment programsmooth out vec3 vVaryingNormal;smooth out vec3 vVaryingLightDir;void main(void)     {     // Get surface normal in eye coordinates    vVaryingNormal = normalMatrix * vNormal;    // Get vertex position in eye coordinates    vec4 vPosition4 = mvMatrix * vVertex;    vec3 vPosition3 = vPosition4.xyz / vPosition4.w;    // Get vector to light source    vVaryingLightDir = normalize(vLightPosition - vPosition3);    // Don't forget to transform the geometry!    gl_Position = mvpMatrix * vVertex;    }

// ADS Point lighting Shader// Fragment Shader// Richard S. Wright Jr.// OpenGL SuperBible#version 130out vec4 vFragColor;uniform vec4    ambientColor;uniform vec4    diffuseColor;   uniform vec4    specularColor;smooth in vec3 vVaryingNormal;smooth in vec3 vVaryingLightDir;void main(void)    {     // Dot product gives us diffuse intensity    float diff = max(0.0, dot(normalize(vVaryingNormal), normalize(vVaryingLightDir)));    // Multiply intensity by diffuse color, force alpha to 1.0    vFragColor = diff * diffuseColor;    // Add in ambient light    vFragColor += ambientColor;    // Specular Light    vec3 vReflection = normalize(reflect(-normalize(vVaryingLightDir), normalize(vVaryingNormal)));    float spec = max(0.0, dot(normalize(vVaryingNormal), vReflection));    if(diff != 0) {        float fSpec = pow(spec, 128.0);        vFragColor.rgb += vec3(fSpec, fSpec, fSpec);        }    }

// DiffuseLight.cpp// OpenGL SuperBible// Demonstrates simple diffuse lighting// Program by Richard S. Wright Jr.#pragma comment(lib, "gltools.lib")#include 
   
    	// OpenGL toolkit#include 
    
     #include 
     
      #include 
      
       #include 
       
        #include 
        
         #include 
         
          #ifdef __APPLE__#include 
          
           #else#define FREEGLUT_STATIC#include 
           
            #endifGLFrame viewFrame;GLFrustum viewFrustum;GLTriangleBatch sphereBatch;GLMatrixStack modelViewMatrix;GLMatrixStack projectionMatrix;GLGeometryTransform transformPipeline;GLShaderManager shaderManager;GLuint ADSLightShader; // The diffuse light shaderGLint locAmbient; // The location of the ambient colorGLint locDiffuse; // The location of the diffuse colorGLint locSpecular; // The location of the specular colorGLint locLight; // The location of the Light in eye coordinatesGLint locMVP; // The location of the ModelViewProjection matrix uniformGLint locMV; // The location of the ModelView matrix uniformGLint locNM; // The location of the Normal matrix uniform// This function does any needed initialization on the rendering// context. void SetupRC(void){ // Background glClearColor(0.0f, 0.0f, 0.0f, 1.0f); glEnable(GL_DEPTH_TEST); glEnable(GL_CULL_FACE); shaderManager.InitializeStockShaders(); viewFrame.MoveForward(4.0f); // Make the sphere gltMakeSphere(sphereBatch, 1.0f, 26, 13); ADSLightShader = shaderManager.LoadShaderPairWithAttributes("ADSPhong.vp", "ADSPhong.fp", 2, GLT_ATTRIBUTE_VERTEX, "vVertex", GLT_ATTRIBUTE_NORMAL, "vNormal"); locAmbient = glGetUniformLocation(ADSLightShader, "ambientColor"); locDiffuse = glGetUniformLocation(ADSLightShader, "diffuseColor"); locSpecular = glGetUniformLocation(ADSLightShader, "specularColor"); locLight = glGetUniformLocation(ADSLightShader, "vLightPosition"); locMVP = glGetUniformLocation(ADSLightShader, "mvpMatrix"); locMV = glGetUniformLocation(ADSLightShader, "mvMatrix"); locNM = glGetUniformLocation(ADSLightShader, "normalMatrix");}// Cleanupvoid ShutdownRC(void){}// Called to draw scenevoid RenderScene(void){ static CStopWatch rotTimer; // Clear the window and the depth buffer glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); modelViewMatrix.PushMatrix(viewFrame); modelViewMatrix.Rotate(rotTimer.GetElapsedSeconds() * 10.0f, 0.0f, 1.0f, 0.0f); GLfloat vEyeLight[] = { -100.0f, 100.0f, 100.0f }; GLfloat vAmbientColor[] = { 0.1f, 0.1f, 0.1f, 1.0f }; GLfloat vDiffuseColor[] = { 0.0f, 0.0f, 1.0f, 1.0f }; GLfloat vSpecularColor[] = { 1.0f, 1.0f, 1.0f, 1.0f }; glUseProgram(ADSLightShader); glUniform4fv(locAmbient, 1, vAmbientColor); glUniform4fv(locDiffuse, 1, vDiffuseColor); glUniform4fv(locSpecular, 1, vSpecularColor); glUniform3fv(locLight, 1, vEyeLight); glUniformMatrix4fv(locMVP, 1, GL_FALSE, transformPipeline.GetModelViewProjectionMatrix()); glUniformMatrix4fv(locMV, 1, GL_FALSE, transformPipeline.GetModelViewMatrix()); glUniformMatrix3fv(locNM, 1, GL_FALSE, transformPipeline.GetNormalMatrix()); sphereBatch.Draw(); modelViewMatrix.PopMatrix(); glutSwapBuffers(); glutPostRedisplay();}void ChangeSize(int w, int h){ // Prevent a divide by zero if (h == 0) h = 1; // Set Viewport to window dimensions glViewport(0, 0, w, h); viewFrustum.SetPerspective(35.0f, float(w) / float(h), 1.0f, 100.0f); projectionMatrix.LoadMatrix(viewFrustum.GetProjectionMatrix()); transformPipeline.SetMatrixStacks(modelViewMatrix, projectionMatrix);}///// Main entry point for GLUT based programsint main(int argc, char* argv[]){ gltSetWorkingDirectory(argv[0]); glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH | GLUT_STENCIL); glutInitWindowSize(800, 600); glutCreateWindow("ADS Lighting, Phong Shading"); glutReshapeFunc(ChangeSize); glutDisplayFunc(RenderScene); GLenum err = glewInit(); if (GLEW_OK != err) { fprintf(stderr, "GLEW Error: %s\n", glewGetErrorString(err)); return 1; } SetupRC(); glutMainLoop(); ShutdownRC(); return 0;}