From b723101be7be773ec4a16137ee68b3059704011a Mon Sep 17 00:00:00 2001
From: bvanroll <beppe.vanrolleghem@gmail.com>
Date: Sat, 8 Jun 2024 00:16:02 +0200
Subject: [PATCH] alles van -1 naar 1 nu

---
 learning/refactor/main.frag     | 94 +++++++++++++++++++++++++++++++++
 learning/shapes/polar_test.frag |  8 +--
 2 files changed, 98 insertions(+), 4 deletions(-)
 create mode 100644 learning/refactor/main.frag

diff --git a/learning/refactor/main.frag b/learning/refactor/main.frag
new file mode 100644
index 0000000..56036d8
--- /dev/null
+++ b/learning/refactor/main.frag
@@ -0,0 +1,94 @@
+#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 hexSDF(vec2 st) {
+  st = abs(st);
+  return max(abs(st.y),st.x*.866025+st.y*.5);
+}
+
+float polySDF(vec2 st, float angles) {
+  float a = atan(st.x,st.y)+PI;
+  float r = length(st);
+  float v = (2.*PI)/angles;
+  return cos(floor(.5+a/v)*v-a)*r;
+}
+
+vec2 rotate(vec2 st, float a) {
+  st = mat2(cos(a),-sin(a),sin(a),cos(a))*(st);
+  return st;
+}
+
+float triSDF(vec2 st) {
+  st = st*2.;
+  return max(abs(st.x)*.866025+st.y*.5,-st.y*.5);
+}
+
+float vesicaSDF(vec2 st, float w) {
+  vec2 offset1 = st-vec2(w,.0);
+  vec2 offset2 = st+vec2(w,.0);
+  float circle1 = length(offset1);
+  float circle2 = length(offset2);
+  return max(circle1, circle2);
+}
+
+float rhombSDF(vec2 st) {
+  vec2 st1 = (st)*2.;
+  vec2 st2 = (vec2(st.x,0.-st.y))*2.;
+  float triangle1 = max(abs(st1.x)*.866025+st1.y*.5,-st1.y*.5);
+  float triangle2 = max(abs(st2.x)*.866025+st2.y*.5,-st2.y*.5);
+  return max(triangle1, triangle2);
+}
+
+float stroke(in float x_coor, float s, float width){
+  float d = step(s,x_coor+width*.5)-step(s,x_coor-width*.5);
+  return clamp(d, 0.,1.);
+}
+
+float crossSDF(vec2 st, float s) {
+  vec2 size = vec2(.25, s);
+  float rect1 = max(abs(st.x/size.x),abs(st.y/size.y));
+  float rect2 = max(abs(st.x/size.y),abs(st.y/size.x));
+  return min(rect1,rect2);
+}
+
+float circle(in vec2 st, in float radius){
+  vec2 dist = st-vec2(.5);
+  return 1.-smoothstep(radius-(radius*.01),
+                       radius+(radius*.01),
+                       dot(st,st)*4.);
+}
+
+void main() {
+  vec2 st = gl_FragCoord.xy/u_resolution;
+  st.x *= u_resolution.x/u_resolution.y;
+  st = (st-.5)*2.;
+  vec3 color = vec3(0.0,0.0,0.0);
+  float alpha = 1.0;
+  //st = rotate(st, radians(90.*sin(u_time)));
+  //color = vec3(hexSDF(st));
+  //color = vec3(polySDF(st, 3.));
+  //color = vec3(
+  //color = vec3(triSDF(st));
+  float v = rhombSDF(st);
+  v = crossSDF(st, .9);
+  v = circle(st, .9);
+  color = vec3(stroke(v,.5,.9));
+  
+
+  gl_FragColor = vec4(color, alpha);
+}
diff --git a/learning/shapes/polar_test.frag b/learning/shapes/polar_test.frag
index 3d5ea09..e5992e9 100644
--- a/learning/shapes/polar_test.frag
+++ b/learning/shapes/polar_test.frag
@@ -44,16 +44,16 @@ void main() {
   m *= u_resolution.x/u_resolution.y;
   m = abs(m);
   float alpha = 1.0;
-  float fq = 2.;
-  float pos = radians(dot(m,m)*360.);
-  float c = circleSDF(st);
+  float fq = 3.;
+  float pos =radians(180.*u_time);
+  float circle = circleSDF(st);
   float r = rectSDF(st, vec2(1.));
   float a = atan(st.y,st.x);
   float f = (cos(a*fq+pos)/2.+.5)*.1;
   float s = polySDF(st, 6.);
   //a = abs(cos(a+u_time))*.1;
   //a = mix(a, .1, sin(u_time));
-  color += stroke(s,.5,.1+f);
+  color += stroke(circle,.5,f);
   //color += c;
   
   gl_FragColor = vec4(color, alpha);