aspect ratio

learning/shapes/circle.frag

@@ -0,0 +1,18 @@
+#ifdef GL_ES
+precision mediump float;
+#endif
+
+uniform vec2 u_resolution;
+uniform vec2 u_mouse;
+uniform float u_time;
+
+#define PI 3.14159265359
+
+void main() {
+  vec2 st = gl_FragCoord.xy/u_resolution;
+  // vec3 color = vec3(0.0,0.0,0.0);
+
+  float pct = distance(gl_FragCoord.xy, (vec2(0.5)*u_resolution)) // find a way to make this a circle even when non 1:1 aspect ratio
+  vec3 color = vec3(pct);
+  gl_FragColor = vec4(color, 1.0);
+}