1 precision mediump float;
2 uniform mediump float uEffectStrength;
3 uniform mediump vec3 uLightPosition;
4 uniform mediump vec2 uLightXYOffset;
5 uniform mediump vec2 uLightSpinOffset;
6 uniform mediump float uLightIntensity;
7 uniform lowp vec4 uColor;
8 uniform sampler2D sTexture;
9 varying mediump vec4 vVertex;
10 varying mediump vec3 vNormal;
11 varying mediump vec2 vTexCoord;
12 varying mediump vec2 vTextureOffset;
14 vec3 rgb2hsl(vec3 rgb)
16 float epsilon = 1.0e-10;
17 vec4 K = vec4(0.0, -1.0 / 3.0, 2.0 / 3.0, -1.0);
18 vec4 P = mix(vec4(rgb.bg, K.wz), vec4(rgb.gb, K.xy), step(rgb.b, rgb.g));
19 vec4 Q = mix(vec4(P.xyw, rgb.r), vec4(rgb.r, P.yzx), step(P.x, rgb.r));
23 float chroma = Q.x - min(Q.w, Q.y);
24 float hue = abs(Q.z + (Q.w-Q.y) / (6.0*chroma+epsilon));
26 float lightness = value - chroma*0.5;
27 return vec3( hue, chroma/max( 1.0-abs(lightness*2.0-1.0), 1.0e-1 ), lightness );
30 vec3 hsl2rgb( vec3 hsl )
33 vec4 K = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
34 vec3 p = abs(fract(hsl.xxx + K.xyz) * 6.0 - K.www);
35 vec3 RGB = clamp(p - K.xxx, 0.0, 1.0);
37 float chroma = ( 1.0 - abs( hsl.z*2.0-1.0 ) ) * hsl.y;
38 return ( RGB - 0.5 ) * chroma + hsl.z;
43 vec3 normal = normalize( vNormal);
45 vec3 lightPosition = uLightPosition + vec3(uLightXYOffset+uLightSpinOffset, 0.0);
46 mediump vec3 vecToLight = normalize( (lightPosition - vVertex.xyz) * 0.01 );
47 mediump float spotEffect = pow( max(0.05, vecToLight.z ) - 0.05, 8.0);
49 spotEffect = spotEffect * uEffectStrength;
50 mediump float lightDiffuse = ( ( dot( vecToLight, normal )-0.75 ) *uLightIntensity ) * spotEffect;
52 lowp vec4 color = texture2D( sTexture, vTexCoord + vTextureOffset * spotEffect );
53 vec3 lightedColor = hsl2rgb( rgb2hsl(color.rgb) + vec3(0.0,0.0,lightDiffuse) );
55 gl_FragColor = vec4( lightedColor, color.a ) * uColor;