fixing errors

07/circle.frag

@@ -10,10 +10,10 @@ uniform vec2 u_mouse;
 uniform float u_time;
 
 float circle(in vec2 _st, in float _radius){
-    vec2 l = _st-vec2(0.5);
+    vec2 dist = _st-vec2(0.5);
 	return 1.-smoothstep(_radius-(_radius*0.01),
                          _radius+(_radius*0.01),
-                         dot(l,l)*4.0);
+                         dot(dist,dist)*4.0);
 }
 
 void main(){

09/tmp/checker.frag

@@ -0,0 +1,32 @@
+// Author @patriciogv ( patriciogonzalezvivo.com ) - 2015
+
+#ifdef GL_ES
+precision mediump float;
+#endif
+
+uniform vec2 u_resolution;
+uniform vec2 u_mouse;
+uniform float u_time;
+
+vec2 tile(vec2 _st, float _zoom){
+  _st *= _zoom;
+  return fract(_st);
+}
+
+float circle(vec2 _st, float _radius){
+  vec2 pos = vec2(0.5)-_st;
+  _radius *= 0.75;
+  return 1.-smoothstep(_radius-(_radius*0.05),_radius+(_radius*0.05),dot(pos,pos)*3.14);
+}
+
+void main(){
+
+  vec2 st = gl_FragCoord.xy/u_resolution.xy;
+  st.x *= u_resolution.x/u_resolution.y;
+
+  float pct = 0.0;
+  vec2 st_i = floor(st*10.);
+  pct += step(0.5,abs(mod(st_i.x,2.)-mod(st_i.y+1.,2.)));
+
+  gl_FragColor = vec4(vec3(pct),1.0);
+}

09/tmp/dots-tide.frag

@@ -0,0 +1,33 @@
+// Author @patriciogv ( patriciogonzalezvivo.com ) - 2015
+
+#ifdef GL_ES
+precision mediump float;
+#endif
+
+uniform vec2 u_resolution;
+uniform vec2 u_mouse;
+uniform float u_time;
+
+vec2 tile(vec2 _st, float _zoom){
+  _st *= _zoom;
+  return fract(_st);
+}
+
+float circle(vec2 _st, float _radius){
+  vec2 pos = vec2(0.5)-_st;
+  _radius *= 0.75;
+  return 1.-smoothstep(_radius-(_radius*0.05),_radius+(_radius*0.05),dot(pos,pos)*3.14);
+}
+
+void main(){
+
+  vec2 st = gl_FragCoord.xy/u_resolution.xy;
+  st.x *= u_resolution.x/u_resolution.y;
+  st = tile(st,5.);
+  float size = .45;
+  float pct = circle(st,size);
+  st = abs(st-.5);
+  pct += circle(st,size);
+
+  gl_FragColor = vec4(vec3(pct),1.0);
+}

09/tmp/dots.frag

@@ -0,0 +1,30 @@
+// Author @patriciogv ( patriciogonzalezvivo.com ) - 2015
+
+#ifdef GL_ES
+precision mediump float;
+#endif
+
+uniform vec2 u_resolution;
+uniform vec2 u_mouse;
+uniform float u_time;
+
+vec2 tile(vec2 _st, float _zoom){
+  _st *= _zoom;
+  return fract(_st);
+}
+
+float circle(vec2 _st, float _radius){
+  vec2 pos = vec2(0.5)-_st;
+  _radius *= 0.75;
+  return 1.-smoothstep(_radius-(_radius*0.05),_radius+(_radius*0.05),dot(pos,pos)*3.14);
+}
+
+void main(){
+
+  vec2 st = gl_FragCoord.xy/u_resolution.xy;
+  st.x *= u_resolution.x/u_resolution.y;
+  st = tile(st,5.);
+  vec3 color = vec3(circle(st, 0.2));
+
+  gl_FragColor = vec4(color,1.0);
+}

09/truchet.frag

@@ -32,13 +32,13 @@ vec2 rotateTilePattern(vec2 _st){
     float index = 0.0;    
     index += step(1., mod(_st.x,2.0));
     index += step(1., mod(_st.y,2.0))*2.0;
-
+    
     //      |
-    //  0   |   1
+    //  2   |   3
     //      |
     //--------------
     //      |
-    //  2   |   3
+    //  0   |   1
     //      |
 
     // Make each cell between 0.0 - 1.0