Merge pull request #26 from bmabsout/patch-2

Created the smooth_cheese.fsh shader

app/src/main/assets/Shaders/smooth_cheese.fsh

@@ -0,0 +1,99 @@
+#version 300 es
+
+/*
+ * Title: Smooth Cheese
+ * Author: Bassel EL Mabsout
+ * SIMPLEX noise implementation taken from: 
+ * https://www.shadertoy.com/view/XsX3zB
+ *
+ * The MIT License
+ * Copyright © 2013 Nikita Miropolskiy
+ * 
+ * ( license has been changed from CCA-NC-SA 3.0 to MIT
+ *
+ *   but thanks for attributing your source code when deriving from this sample 
+ *   with a following link: https://www.shadertoy.com/view/XsX3zB )
+ */
+
+precision highp float;
+
+uniform float iTime;
+uniform vec3 iResolution;
+
+in vec2 textureCoord;
+out vec4 fragColor;
+
+/* discontinuous pseudorandom uniformly distributed in [-0.5, +0.5]^3 */
+vec3 random3(vec3 c) {
+	float j = 4096.0*sin(dot(c,vec3(17.0, 59.4, 15.0)));
+	vec3 r;
+	r.z = fract(512.0*j);
+	j *= .125;
+	r.x = fract(512.0*j);
+	j *= .125;
+	r.y = fract(512.0*j);
+	return r-0.5;
+}
+
+/* skew constants for 3d simplex functions */
+const float F3 =  0.3333333;
+const float G3 =  0.1666667;
+
+/* 3d simplex noise */
+float simplex3d(vec3 p) {
+	 /* 1. find current tetrahedron T and it's four vertices */
+	 /* s, s+i1, s+i2, s+1.0 - absolute skewed (integer) coordinates of T vertices */
+	 /* x, x1, x2, x3 - unskewed coordinates of p relative to each of T vertices*/  
+	 /* calculate s and x */
+	 vec3 s = floor(p + dot(p, vec3(F3)));
+	 vec3 x = p - s + dot(s, vec3(G3));
+
+	 /* calculate i1 and i2 */
+	 vec3 e = step(vec3(0.0), x - x.yzx);
+	 vec3 i1 = e*(1.0 - e.zxy);
+	 vec3 i2 = 1.0 - e.zxy*(1.0 - e);
+
+	 /* x1, x2, x3 */
+	 vec3 x1 = x - i1 + G3;
+	 vec3 x2 = x - i2 + 2.0*G3;
+	 vec3 x3 = x - 1.0 + 3.0*G3;
+
+	 /* 2. find four surflets and store them in d */
+	 vec4 w, d;
+
+	 /* calculate surflet weights */
+	 w.x = dot(x, x);
+	 w.y = dot(x1, x1);
+	 w.z = dot(x2, x2);
+	 w.w = dot(x3, x3);
+
+	 /* w fades from 0.6 at the center of the surflet to 0.0 at the margin */
+	 w = max(0.6 - w, 0.0);
+
+	 /* calculate surflet components */
+	 d.x = dot(random3(s), x);
+	 d.y = dot(random3(s + i1), x1);
+	 d.z = dot(random3(s + i2), x2);
+	 d.w = dot(random3(s + 1.0), x3);
+
+	 /* multiply d by w^4 */
+	 w *= w;
+	 w *= w;
+	 d *= w;
+
+	 /* 3. return the sum of the four surflets */
+	 return dot(d, vec4(52.0));
+}
+
+void main()
+{
+	vec2 p = textureCoord;
+	vec3 p3 = vec3(p, iTime*0.015)+vec3(iTime*0.015,0.0,0.0);
+
+	float value = pow(abs(simplex3d(p3*2.0)),1.5);
+	float red = 0.5 + 0.5*simplex3d(p3*2.0 + 38274.9);
+	float green = abs(0.2+0.5*simplex3d(p3*2.0 + 3824.9));
+	float blue = abs(simplex3d(p3*2.0 + 98274.9));
+
+	fragColor = vec4(sqrt(value*vec3(red, green, blue)), 1.0);
+}