From 01a8e0a656deabe44b5103cfc0322f4132b536d8 Mon Sep 17 00:00:00 2001
From: hellerve <veit@veitheller.de>
Date: Tue, 6 Jun 2017 12:01:53 -0400
Subject: [PATCH] weird: added hud

---
 weird/hud.glsl | 105 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 105 insertions(+)
 create mode 100644 weird/hud.glsl

diff --git a/weird/hud.glsl b/weird/hud.glsl
new file mode 100644
index 0000000..1b167c8
--- /dev/null
+++ b/weird/hud.glsl
@@ -0,0 +1,105 @@
+#ifdef GL_ES
+precision mediump float;
+#endif
+
+#define PI 3.14159265359
+#define blue1 vec3(0.74,0.95,1.00)
+#define blue2 vec3(0.87,0.98,1.00)
+#define blue3 vec3(0.35,0.76,0.83)
+#define blue4 vec3(0.953,0.969,0.89)
+#define red   vec3(1.00,0.38,0.227)
+
+uniform vec2 u_resolution;
+uniform float u_time;
+
+mat2 rotate2d(float a) {
+    float c = cos(a);
+    return mat2(c, -sin(a), sin(a), c);
+}
+
+vec2 get_center() {
+    return(u_resolution/2.)/min(u_resolution.x, u_resolution.y);
+}
+
+vec2 get_st() {
+    return gl_FragCoord.xy/min(u_resolution.x, u_resolution.y);
+}
+
+float dist(vec2 center) {  
+    vec2 st = get_st();
+    return distance(st, center); 
+}
+
+vec3 circle(vec2 center, float width, float rad, vec3 color) {
+    float e = 0.003;
+    float d = dist(center);
+    vec3 res = color;
+    res *= smoothstep(rad-width/2.-e, rad-width/2., d);
+    res *= 1.-smoothstep(rad+width/2., rad+width/2.+e, d);
+    return res;
+}
+
+vec3 circle_with_trace(vec2 center, float width, float rad, vec3 color) {
+    float e = 0.003;
+    float d = dist(center);
+    float trace = 0.08;
+    vec3 res = color;
+    res *= smoothstep(rad-width/2.-e, rad-width/2., d);
+    res *= 1.-smoothstep(rad+width/2., rad+width/2.+e, d);
+    return (res+color*.5*(smoothstep(rad-trace, rad, d)-step(rad, d)));
+}
+
+float circle_clip(float radius) {
+    float d = dist(get_center());
+    return 1.-step(radius, d);
+}
+
+vec3 floating_circle() {
+    vec2 pos = vec2(cos(u_time)*sin(u_time), sin(u_time))*.5+get_center();
+    return circle(pos, 0.002, 0.002, vec3(1.));
+}
+
+vec3 line(float width, float angle, vec3 color, vec2 origin) {
+    float e = 0.003;
+    vec2 st = get_st();
+    st -= origin;
+    st *= rotate2d(angle);
+    return color*((smoothstep(-e, 0., st.x)-smoothstep(0., e, st.x)));
+}
+
+vec3 line_with_trace(float width, float angle, vec3 color, vec2 origin) {
+    float e = 0.003;
+    float trace = 0.9 * dist(get_center());
+    vec2 origst = get_st();
+    vec2 st = origst - origin;
+    st *= rotate2d(angle);
+    return (color*(smoothstep(-e, 0., st.x)-smoothstep(0., e, st.x))+color*.5*(step(0., st.x)-smoothstep(0., trace, st.x)))*step(0., -st.y);
+}
+
+vec3 target() {
+    vec2 center = vec2(cos(u_time*0.5), sin(u_time*0.5))*0.2+get_center()+vec2(cos(u_time*0.3), sin(u_time*0.3))*0.25;
+    vec3 blink = circle(center, 0.01, 0.005, red) * step(0.5, abs(sin(u_time*8.)));
+    vec3 border = circle(center, 0.003, 0.02, red);
+    vec3 impulse = circle_with_trace(center, 0.003, mod(u_time, 1.)*0.12+0.03, red);
+    return blink+border+impulse;
+}
+
+void main(){
+    vec3 color = vec3(0.0);
+    vec2 st = get_st();
+    float clip = circle_clip(.5);
+    
+    
+	color += circle(get_center(), 0.002, 0.02, blue1);
+	color += circle(get_center(), 0.002, 0.3, blue1);
+	color += circle(get_center(), 0.002, 0.4, blue1);
+	color += circle(get_center(), 0.005, 0.5, vec3(0.8));  
+	color += circle(get_center(), 0.007, 0.6, blue1);
+    color += clip*line(0.001, PI/4., vec3(.5), get_center());
+    color += clip*line(0.001, -PI/4., vec3(.5), get_center());   
+    color += clip*line_with_trace(0.001, u_time, blue2, get_center());
+    color += floating_circle();
+    color += target();
+    
+    gl_FragColor = vec4(color,1.0);
+}