37 lines
947 B
Bash
37 lines
947 B
Bash
precision mediump float;
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varying vec2 vTextureCoord; //接收从顶点着色器过来的参数
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uniform sampler2D sTexture;//纹理内容数据
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varying float currY;
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uniform sampler2D sTextureGrass;//纹理内容数据（草皮）
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uniform sampler2D sTextureRock;//纹理内容数据（岩石）
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uniform float landStartY;//陆地起始Y
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uniform float landYSpan;//陆地Y偏移量
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void main()
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{
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float min=0.25;
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float max=0.7;
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float currYRatio=(currY-landStartY)/landYSpan;
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vec4 gColor=texture2D(sTextureGrass, vTextureCoord);
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vec4 rColor=texture2D(sTextureRock, vTextureCoord);
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vec4 finalColor;
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if(currYRatio<min)
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{
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finalColor=gColor;
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}
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else if(currYRatio>max)
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{
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finalColor=rColor;
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}
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else
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{
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float rockBL=(currYRatio-min)/(max-min);
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finalColor=rockBL*rColor+(1.0-rockBL)*gColor;
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}
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//给此片元从纹理中采样出颜色值
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gl_FragColor = finalColor;
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} |