卡通(Toon)着色

CPU端代码设置:

// This function does any needed initialization on the rendering// context. void SetupRC(void){// BackgroundglClearColor(0.025f, 0.25f, 0.25f, 1.0f );glEnable(GL_DEPTH_TEST);    shaderManager.InitializeStockShaders();    viewFrame.MoveForward(4.0f);    // Make the torus    gltMakeTorus(torusBatch, .80f, 0.25f, 52, 26);toonShader = gltLoadShaderPairWithAttributes("ToonShader.vp", "ToonShader.fp", 2, GLT_ATTRIBUTE_VERTEX, "vVertex",GLT_ATTRIBUTE_NORMAL, "vNormal");locLight = glGetUniformLocation(toonShader, "vLightPosition");locMVP = glGetUniformLocation(toonShader, "mvpMatrix");locMV  = glGetUniformLocation(toonShader, "mvMatrix");locNM  = glGetUniformLocation(toonShader, "normalMatrix");        locColorTable = glGetUniformLocation(toonShader, "colorTable");glGenTextures(1, &texture);glBindTexture(GL_TEXTURE_1D, texture);GLubyte textureData[4][3] = { 32,  0, 0,                                      64,  0, 0,                                                  128, 0, 0,                              255, 0, 0};glTexImage1D(GL_TEXTURE_1D, 0, GL_RGB, 4, 0, GL_RGB, GL_UNSIGNED_BYTE, textureData);glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);}

顶点着色器:

// Cell lighting Shader// Vertex Shader// Richard S. Wright Jr.// OpenGL SuperBible#version 130// Incoming per vertex... position and normalin vec4 vVertex;in vec3 vNormal;smooth out float textureCoordinate;uniform vec3vLightPosition;uniform mat4mvpMatrix;uniform mat4mvMatrix;uniform mat3normalMatrix;void main(void)     {     // Get surface normal in eye coordinates    vec3 vEyeNormal = normalMatrix * vNormal;    // Get vertex position in eye coordinates    vec4 vPosition4 = mvMatrix * vVertex;    vec3 vPosition3 = vPosition4.xyz / vPosition4.w;    // Get vector to light source    vec3 vLightDir = normalize(vLightPosition - vPosition3);    // Dot product gives us diffuse intensity    textureCoordinate = max(0.0, dot(vEyeNormal, vLightDir)); // cos(theta), 值越大说明夹角越小, 对应的颜色越亮    // Don't forget to transform the geometry!    gl_Position = mvpMatrix * vVertex;    }

片断着色器：

// Cell lighting Shader// Fragment Shader// Richard S. Wright Jr.// OpenGL SuperBible#version 130uniform sampler1D colorTable;out vec4 vFragColor;smooth in float textureCoordinate;void main(void)   {    vFragColor = texture(colorTable, textureCoordinate);   }

 

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