4_0_gnoise
コード 4.1, 図 4.3:
4_0_gnoise.frag
#version 300 esprecision highp float;precision highp int;out vec4 fragColor;uniform float u_time;uniform vec2 u_resolution;int channel;//start hashuvec3 k = uvec3(0x456789abu, 0x6789ab45u, 0x89ab4567u);uvec3 u = uvec3(1, 2, 3);const uint UINT_MAX = 0xffffffffu;uint uhash11(uint n){n ^= (n << u.x);n ^= (n >> u.x);n *= k.x;n ^= (n << u.x);return n * k.x;}uvec2 uhash22(uvec2 n){n ^= (n.yx << u.xy);n ^= (n.yx >> u.xy);n *= k.xy;n ^= (n.yx << u.xy);return n * k.xy;}uvec3 uhash33(uvec3 n){n ^= (n.yzx << u);n ^= (n.yzx >> u);n *= k;n ^= (n.yzx << u);return n * k;}float hash11(float p){uint n = floatBitsToUint(p);return float(uhash11(n)) / float(UINT_MAX);}float hash21(vec2 p){uvec2 n = floatBitsToUint(p);return float(uhash22(n).x) / float(UINT_MAX);}float hash31(vec3 p){uvec3 n = floatBitsToUint(p);return float(uhash33(n).x) / float(UINT_MAX);}vec2 hash22(vec2 p){uvec2 n = floatBitsToUint(p);return vec2(uhash22(n)) / vec2(UINT_MAX);}vec3 hash33(vec3 p){uvec3 n = floatBitsToUint(p);return vec3(uhash33(n)) / vec3(UINT_MAX);}//end hashfloat gnoise21(vec2 p){vec2 n = floor(p);vec2 f = fract(p);float[4] v;for (int j = 0; j < 2; j ++){for (int i = 0; i < 2; i++){vec2 g = normalize(hash22(n + vec2(i,j)) - vec2(0.5));v[i+2*j] = dot(g, f - vec2(i, j));}}f = f * f * f * (10.0 - 15.0 * f + 6.0 * f * f);return 0.5 * mix(mix(v[0], v[1], f[0]), mix(v[2], v[3], f[0]), f[1]) + 0.5;}float gnoise31(vec3 p){vec3 n = floor(p);vec3 f = fract(p);float[8] v;for (int k = 0; k < 2; k++ ){for (int j = 0; j < 2; j++ ){for (int i = 0; i < 2; i++){vec3 g = normalize(hash33(n + vec3(i, j, k)) - vec3(0.5));v[i+2*j+4*k] = dot(g, f - vec3(i, j, k));}}}f = f * f * f * (10.0 - 15.0 * f + 6.0 * f * f);float[2] w;for (int i = 0; i < 2; i++){w[i] = mix(mix(v[4*i], v[4*i+1], f[0]), mix(v[4*i+2], v[4*i+3], f[0]), f[1]);}return 0.5 * mix(w[0], w[1], f[2]) + 0.5;}void main(){vec2 pos = gl_FragCoord.xy/min(u_resolution.x, u_resolution.y);channel = int(gl_FragCoord.x * 2.0 / u_resolution.x);pos = 10.0 * pos + u_time;if (channel < 1){fragColor = vec4(gnoise21(pos)); //left} else {fragColor = vec4(gnoise31(vec3(pos, u_time)));}fragColor.a = 1.0;}