some basic shaders

src/lib/shaders/basic.vert

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+void main() {
+    gl_Position = vec4( position, 1.0 );
+}

src/lib/shaders/utils/brickTile.frag

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+precision mediump float;
+
+vec2 brickTile(vec2 _st, float _zoom){
+    _st *= _zoom;
+
+    // Here is where the offset is happening
+    _st.x += step(1., mod(_st.y,2.0)) * 0.5;
+
+    return fract(_st);
+}

src/lib/shaders/utils/circle.frag

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+precision mediump float;
+
+mediump float circle(in vec2 _st, in float _radius){
+    vec2 dist = _st-vec2(0.5);
+	return 1.-smoothstep(_radius-(_radius*0.01),
+        _radius+(_radius*0.01),
+        dot(dist,dist)*4.0);
+}

src/lib/shaders/utils/cog.frag

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+precision mediump float;
+
+mediump float cog(in vec2 st){
+    vec2 pos = vec2(0.5)-st;
+
+    float r = length(pos)*2.0;
+    float a = atan(pos.y,pos.x);
+
+    return smoothstep(
+        -1.2, // lower cog part
+        1.5,  // upper cog part
+        cos(
+            a * 10. // number of teeth
+        ))
+    *0.5 // inner size
+    + 0.5; // outer size
+}

src/lib/shaders/utils/move.frag

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+precision mediump float;
+
+vec2 move(in vec2 st, in vec2 move) {
+    return st + move;
+}

src/lib/shaders/utils/polygon.frag

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+precision mediump float;
+
+#define PI 3.14159265359
+#define TWO_PI 6.28318530718
+
+// sides should probably be an integer, but it can be abused for morphin effects
+mediump float polygon(in vec2 st, in float sides){
+    vec3 color = vec3(0.0);
+
+    // Remap the space to -1. to 1.
+    st = st *2. -1.;
+
+    // Angle and radius from the current pixel
+    float a = atan(st.x,st.y)+PI;
+    float r = TWO_PI/float(sides);
+
+    // Shaping function that modulate the distance
+    return cos(floor(0.500+a/r)*r-a)*length(st);
+    // when it's not 0.5 exactly, the triangles will not match perfectly for the polygon to take shape. Can be abused for cool effects
+    // (possibly transitions)
+}

src/lib/shaders/utils/random.frag

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+precision mediump float;
+
+float random (vec2 st) {
+    return fract(sin(dot(st.xy,
+        vec2(12.9898,78.233)))*
+        43758.5453123);
+}
+
+vec2 random2(vec2 st){
+    st = vec2( dot(st,vec2(127.1,311.7)),
+              dot(st,vec2(269.5,183.3)) );
+    return -1.0 + 2.0*fract(sin(st)*43758.5453123);
+}
+
+// Gradient Noise by Inigo Quilez - iq/2013
+// https://www.shadertoy.com/view/XdXGW8
+float noise(vec2 st) {
+    vec2 i = floor(st);
+    vec2 f = fract(st);
+
+    vec2 u = f*f*(3.0-2.0*f);
+
+    return mix( mix( dot( random2(i + vec2(0.0,0.0) ), f - vec2(0.0,0.0) ),
+                     dot( random2(i + vec2(1.0,0.0) ), f - vec2(1.0,0.0) ), u.x),
+                mix( dot( random2(i + vec2(0.0,1.0) ), f - vec2(0.0,1.0) ),
+                     dot( random2(i + vec2(1.0,1.0) ), f - vec2(1.0,1.0) ), u.x), u.y);
+}

src/lib/shaders/utils/repeat.frag

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+precision mediump float;
+
+vec2 repeat(in vec2 st, in float repeat) {
+    return st * repeat;
+}
+
+vec2 repeat(in vec2 st, in vec2 repeat) {
+    return vec2(st.x * repeat.x, st.y * repeat.y);
+}

src/lib/shaders/utils/rotate2d.frag

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+precision mediump float;
+
+mat2 mat_rotate2d(in float angle){
+    return mat2(cos(angle),-sin(angle),
+        sin(angle),cos(angle));
+}
+
+vec2 rotate2d(in vec2 _st, in float angle) {
+    vec2 st = _st;
+    st -= 0.5;
+    st *= mat_rotate2d(angle);
+    st += 0.5;
+    return st;
+}

src/lib/shaders/utils/scale.frag

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+precision mediump float;
+
+mat2 mat_scale(vec2 _scale){
+    return mat2(_scale.x,0.0,
+                0.0,_scale.y);
+}
+
+vec2 scale(in vec2 _st, in vec2 _scale) {
+    vec2 st = _st;
+    st -= 0.5;
+    st *= mat_scale(_scale);
+    st += 0.5;
+    return st;
+}