port from perforce

hgplus/ShaderMinifier/tests/real/motion_blur.frag

@@ -0,0 +1,41 @@
+uniform vec2 resolution;
+uniform float time;
+uniform sampler2D tex0;
+uniform sampler2D tex1;
+uniform sampler2D tex2;
+uniform sampler2D tex3;
+
+vec3 deform( in vec2 p, float scale )
+{
+    vec2 uv;
+   
+    float mtime = scale+time;
+    float a = atan(p.y,p.x);
+    float r = sqrt(dot(p,p));
+    float s = r * (1.0+0.5*cos(mtime*1.7));
+
+    uv.x = .1*mtime +.05*p.y+.05*cos(-mtime+a*3.0)/s;
+    uv.y = .1*mtime +.05*p.x+.05*sin(-mtime+a*3.0)/s;
+
+    float w = 0.8-0.2*cos(mtime+3.0*a);
+
+    vec3 res = texture2D(tex0,uv).xyz*w;
+    return  res*res;
+
+}
+
+void main(void)
+{
+    vec2 p = -1.0 + 2.0 * gl_FragCoord.xy / resolution.xy;
+    vec3 total = vec3(0.0);
+    float w = 0.0;
+    for( int i=0; i<20; i++ )
+    {
+        vec3 res = deform(p,w);
+        total += res;
+        w += 0.02;
+    }
+    total /= 20.0;
+
+    gl_FragColor = vec4( 3.0*total,1.0);
+}