ok, kben er

experiments/exercises/offset_patterns.frag

@@ -1,43 +1,6 @@
-#ifdef GL_ES
 precision mediump float;
-#endif
-uniform vec2 u_resolution;
-uniform vec2 u_mouse;
-uniform float u_time;
-
-#define PI 3.14159265359
-
-const vec3 uAColor = vec3(.5,.5,.5);
-const vec3 uBColor = vec3(.5,.5,.5);
-const vec3 uCColor = vec3(1.,1.,1.);
-const vec3 uDColor = vec3(.0,.33,.67);
-
-//get colors from http://dev.thi.ng/gradients/
-vec3 cosPalette(float t) { return uAColor + uBColor*cos(6.28318*(uCColor*t+uDColor)); }
-
-float fill(float x, float size) { return 1.-step(size, x); }
-
-float circleSDF(vec2 st) { return length(st); }
-
-void main() {
-  vec2 st = (gl_FragCoord.xy*2. - u_resolution.xy)/u_resolution.y;
-  vec3 color = vec3(0.0,0.0,0.0);
-  float alpha = 1.0;
-  float sp = u_time/8.;
-  float m = step(mod(sp*10.,2.),1.);
-  vec2 st2 = st;
-  //vec2 st2 = fract(st*10.)-.5;
-  vec2 u = vec2(1.);
-  u.x = step(mod(st2.y*10.,2.),1.)*2.-1.;
-  u.y = step(mod(st2.x*10.,2.),1.)*2.-1.;
-  st2.x += u.x*fract(sp*m);
-  st2.y += u.y*fract(sp*(1.-m));
-  st2 = fract(st2*10.)-.5;
-  st2 *= 2.;
-  float circle = (circleSDF(st2));
-  float circle2 = (circle);
-  color += fill(circle,.2);
-  color += fill(min(circle,circle2),.5);
-
-  gl_FragColor = vec4(color, alpha);
-}
+uniform vec2 iResolution;
+uniform float iTime;
+float fi(float x,float s){return 1.-step(s, x);}
+float cs(vec2 s){return length(s);}
+void main(){vec2 st=(gl_FragCoord.xy*2.-iResolution.xy)/iResolution.y; vec3 co=vec3(0.0);float sp=iTime/8.;float m=step(mod(sp*10.,2.),1.);vec2 st2=st;vec2 u=vec2(1.);u.x=step(mod(st2.y*10.,2.),1.)*2.-1.;u.y=step(mod(st2.x*10.,2.),1.)*2.-1.;st2.x+=u.x*fract(sp*m);st2.y+=u.y*fract(sp*(1.-m));st2=fract(st2*10.)-.5;st2*=2.;float c=(cs(st2));float c2=(c);co+=fi(c,.2);co+=fi(min(c,c2),.5);gl_FragColor=vec4(co, 1.);}

learning/patterns/rotates.frag

@@ -0,0 +1,59 @@
+#ifdef GL_ES
+precision mediump float;
+#endif
+uniform vec2 u_resolution;
+uniform vec2 u_mouse;
+uniform float u_time;
+
+#define PI 3.14159265359
+
+vec2 rotate2D (vec2 st, float angle) {
+  st -= .5;
+  st = mat2(cos(angle),-sin(angle),
+            sin(angle),cos(angle))*st;
+  st += .5;
+  return st;
+
+}
+
+vec2 tile (vec2 st, float zoom) {
+  st *= zoom;
+  return fract(st);
+}
+
+vec2 rotateTilePatter(vec2 st) {
+  st *= 2.;
+  float index = 0.0;
+  index += step(1., mod(st.x,2.));
+  index += step(1.,mod(st.y,2.))*2.;
+  st = fract(st);
+
+  if(index == 1.) {
+    st = rotate2D(st, PI*.5);
+  } else if (index == 2.){
+    st = rotate2D(st, PI*-.5);
+  } else if (index == 3.){
+    st = rotate2D(st, PI);
+  }
+
+  return st;
+}
+
+
+void main() {
+  vec2 st = (gl_FragCoord.xy*2. - u_resolution.xy)/u_resolution.y;
+//  vec2 st = gl_FragCoord.xy/u_resolution.xy;
+
+  vec3 color = vec3(0.0,0.0,0.0);
+  float alpha = 1.0;
+  st = fract(st*2.);
+  st = rotateTilePatter(st);
+  
+  color += step(st.x,st.y);
+
+
+
+  
+
+  gl_FragColor = vec4(color, alpha);
+}