cocos2dx Material System讲解一

- 日理万妓 2022-08-09 14:44 142阅读 0赞

cocos2dx 增加了材料系统，因为之前我深入研究过RenderMonkey这个软件，又深入学习了OpenGl es2.0，所以理解起来还是挺轻松的。但是有些写法还是不太一样，所以在这里记下，和大家分享一下。

首先，我们先看一个material：

material mf
    {
    
    technique m0
       {
       pass 0
       {
           renderState
           {
               cullFace=true
               depthTest=true
           }
           shader
           {
               vertexShader=shaders/molecular_formula.vert
               fragmentShader=shaders/molecular_formula.frag
               u_lightLocation=0,0,0
               u_Camera=0,0,0
               uColorR=0.1
               uColorG=0.6
               uColorB=0.9
               uColorA=0.0
    		   transparent=0.0
           }
       }
       }
    
       technique m1
       {
       pass 1
       {
           renderState
           {
               cullFace=true
               depthTest=true
           }
           shader
           {
               vertexShader=shaders/molecular_formula.vert
               fragmentShader=shaders/molecular_formula.frag
               u_lightLocation=0,0,0
               u_Camera=0,0,0
               uColorR=0.1
               uColorG=0.6
               uColorB=0.9
               uColorA=1.0
    		   transparent=0.7
           }
       }
       }
    
     technique m2
       {
       pass 2
       {
           renderState
           {
               cullFace=true
               depthTest=true
           }
           shader
           {
               vertexShader=shaders/molecular_formula.vert
               fragmentShader=shaders/molecular_formula.frag
               u_lightLocation=0,0,-20
               u_Camera=0,0,10
               uColorR=0.95
               uColorG=0.95
               uColorB=0.10
               uColorA=1.0
    		   transparent=0.7
           }
       }
       }
    
        technique m3
       {
       pass 3
       {
           renderState
           {
               cullFace=true
               depthTest=true
           }
           shader
           {
               vertexShader=shaders/molecular_formula.vert
               fragmentShader=shaders/molecular_formula.frag
               u_lightLocation=10,0,-20
               u_Camera=0,0,100
               uColorR=0.95
               uColorG=0.45
               uColorB=0.25
               uColorA=1.0
    		   transparent=0.7
           }
       }
       }
    
        technique m4
       {
       pass 1
       {
           renderState
           {
               cullFace=true
               depthTest=true
           }
           shader
           {
               vertexShader=shaders/molecular_formula.vert
               fragmentShader=shaders/molecular_formula.frag
               u_lightLocation=-100,0,100
               u_Camera=100,0,50
               uColorR=0.1
               uColorG=0.6
               uColorB=0.9
               uColorA=1.0
    		   transparent=0.7
           }
       }
       }
    
    }

molecular\_formula.vert

attribute vec4 a_position;
    attribute vec3 a_normal;
    attribute vec2 a_texCoord;
    
    uniform vec3 u_lightLocation;
    uniform vec3 u_Camera;
    
    varying vec2 v_texture_coord;
    varying vec4 v_ambient;
    varying vec4 v_diffuse;
    varying vec4 v_specular;
    
    void pointLight(
      in vec3 normal,
      inout vec4 ambient,
      inout vec4 diffuse,
      inout vec4 specular,
      in vec3 lightLocation,
      in vec4 lightAmbient,
      in vec4 lightDiffuse,
      in vec4 lightSpecular
     ){
      ambient=lightAmbient;
      vec3 normalTarget= a_position.xyz+normal;
      vec3 newNormal=(CC_MVMatrix*vec4(normalTarget,1)).xyz-(CC_MVMatrix*a_position).xyz;
      newNormal=normalize(newNormal);
      vec3 eye=normalize(u_Camera-(CC_MVMatrix*a_position).xyz);
      vec3 vp=normalize(lightLocation-(CC_MVMatrix*a_position).xyz);
      vp=normalize(vp);
      vec3 halfVector=normalize(vp+eye);
      float shininess=50.0;
      float nDotViewPosition=max(0.0,dot(newNormal,vp));
      diffuse=lightDiffuse*nDotViewPosition;
      float nDotViewHalfVector=dot(newNormal,halfVector);
      float powerFactor=max(0.0,pow(nDotViewHalfVector,shininess));
      specular=lightSpecular*powerFactor;
      }
    
    void main(void)
    {
        gl_Position = CC_MVPMatrix * a_position;
        
        vec4 ambientTemp,diffuseTemp,specularTemp;
        
        pointLight(normalize(a_normal),ambientTemp,diffuseTemp,specularTemp,u_lightLocation,
        vec4(0.8,0.8,0.8,1.0),vec4(0.8,0.8,0.8,1.0),vec4(0.9,0.9,0.9,1.0));
        
        v_ambient=ambientTemp;
        v_diffuse=diffuseTemp;
        v_specular=specularTemp;
        
        v_texture_coord = a_texCoord;
        v_texture_coord.y = (1.0 - v_texture_coord.y);
    }

molecular\_formula.frag

#ifdef GL_ES
    precision mediump float;
    #endif
    
    uniform vec4  u_color;
    uniform float uColorR;
    uniform float uColorG;
    uniform float uColorB;
    uniform float uColorA;
    uniform float transparent;
    
    varying vec4 v_ambient;
    varying vec4 v_diffuse;
    varying vec4 v_specular;
    
    void main(void)
    {
    	 vec4 finalColor =vec4(uColorR,uColorG,uColorB,uColorA);
    	 vec4 color=finalColor*v_ambient+finalColor*v_diffuse+finalColor*v_specular;
         gl_FragColor=color*u_color*transparent;
        
    }

下面是效果图：

![20151028101342606][]

未完待续

[20151028101342606]: /images/20220731/1bb4a136a8444355a49d084897866ae6.png