float hash(vec4 p) { p = fract(p * 0.3183099 + 0.1); p *= 17.0; return (fract(p.x * p.y * p.z * p.w * (p.x + p.y + p.z + p.w)) - 0.5) * 2.0; } float snoise(in vec4 x) { vec4 p = floor(x); vec4 f = fract(x); f = f * f * (3.0 - 2.0 * f); return mix( mix( mix( mix(hash(p + vec4(0,0,0,0)), hash(p + vec4(1,0,0,0)), f.x), mix(hash(p + vec4(0,1,0,0)), hash(p + vec4(1,1,0,0)), f.x), f.y), mix( mix(hash(p + vec4(0,0,1,0)), hash(p + vec4(1,0,1,0)), f.x), mix(hash(p + vec4(0,1,1,0)), hash(p + vec4(1,1,1,0)), f.x), f.y), f.z), mix( mix( mix(hash(p + vec4(0,0,0,1)), hash(p + vec4(1,0,0,1)), f.x), mix(hash(p + vec4(0,1,0,1)), hash(p + vec4(1,1,0,1)), f.x), f.y), mix( mix(hash(p + vec4(0,0,1,1)), hash(p + vec4(1,0,1,1)), f.x), mix(hash(p + vec4(0,1,1,1)), hash(p + vec4(1,1,1,1)), f.x), f.y), f.z), f.w); } vec3 rand_perm_3(vec3 pos) { return abs(sin(pos * vec3(1473.7 * pos.z + 472.3, 8891.1 * pos.x + 723.1, 3813.3 * pos.y + 982.5))); } vec4 rand_perm_4(vec4 pos) { return sin(473.3 * pos * vec4(317.3 * pos.w + 917.7, 1473.7 * pos.z + 472.3, 8891.1 * pos.x + 723.1, 3813.3 * pos.y + 982.5) / pos.yxwz); } vec3 smooth_rand(vec3 pos, float lerp_axis) { return vec3(snoise(vec4(pos, lerp_axis)), snoise(vec4(pos + 400.0, lerp_axis)), snoise(vec4(pos + 1000.0, lerp_axis))); vec3 r0 = rand_perm_3(vec3(pos.x, pos.y, pos.z) + floor(lerp_axis)); vec3 r1 = rand_perm_3(vec3(pos.x, pos.y, pos.z) + floor(lerp_axis + 1.0)); return r0 + (r1 - r0) * fract(lerp_axis); }