smoothstep lijkt super interessant

learning/shaping/main.frag

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+#ifdef GL_ES
+precision mediump float;
+#endif
+
+uniform vec2 u_resolution;
+uniform vec2 u_mouse;
+uniform float u_time;
+
+// Plot a line on Y using a value between 0.0-1.0
+float plot(vec2 st) {
+  return smoothstep(0.02,0.0, abs(st.y - st.x));
+}
+
+void main() {
+  vec2 st = gl_FragCoord.xy/u_resolution;
+  float y = st.x;
+
+  vec3 color = vec3(y);
+
+  float pct = plot(st);
+  color = (1.0-pct)*color+pct*vec3(0.0,1.0,0.0);
+
+  gl_FragColor = vec4(color, 1.0);
+}

learning/shaping/pow.frag

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+#ifdef GL_ES
+precision mediump float;
+#endif
+
+uniform vec2 u_resolution;
+uniform vec2 u_mouse;
+uniform float u_time;
+
+#define PI 3.14159265359
+
+
+// Plot a line on Y using a value between 0.0-1.0
+float plot(vec2 st, float pct) {
+  return smoothstep( pct-0.02, pct, st.y) - smoothstep( pct, pct+0.02, st.y);
+}
+
+void main() {
+  vec2 st = gl_FragCoord.xy/u_resolution;
+  // float y = pow(st.x, 2.0);
+  // float y = pow(st.x, PI);
+  float y = sqrt(st.x);
+  vec3 color = vec3(y);
+
+  float pct = plot(st,y);
+  color = (1.0-pct)*color+pct*vec3(0.0,1.0,0.0);
+
+  gl_FragColor = vec4(color, 1.0);
+}

learning/shaping/step.frag

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+#ifdef GL_ES
+precision mediump float;
+#endif
+
+uniform vec2 u_resolution;
+uniform vec2 u_mouse;
+uniform float u_time;
+
+#define PI 3.14159265359
+
+
+// Plot a line on Y using a value between 0.0-1.0
+float plot(vec2 st, float pct) {
+  return smoothstep( pct-0.02, pct, st.y) - smoothstep( pct, pct+0.02, st.y);
+}
+
+void main() {
+  vec2 st = gl_FragCoord.xy/u_resolution;
+  // float y = pow(st.x, 2.0);
+  // float y = pow(st.x, PI);
+  // float y = sqrt(st.x);
+  // float y = step(0.5, st.x);
+  // float y = smoothstep(0.3,0.9,st.x);
+  // this code creates a smooth gradient for a line edge from 0.4 to 0.5 and 0.5 to 0.6 since it's only checking the x coors
+  float y = smoothstep(0.4,0.5,st.x) - smoothstep(0.5,0.6,st.x);
+  vec3 color = vec3(y);
+
+  float pct = plot(st,y);
+  color = (1.0-pct)*color+pct*vec3(0.0,1.0,0.0);
+
+  gl_FragColor = vec4(color, 1.0);
+}