Stefan Dresselhaus
5f313c4495
- added fps to window-name - hsSDL2 needs update (as i changed functions in there which got merged) - wrote simplistic procedural texture shader
129 lines
3.6 KiB
GLSL
129 lines
3.6 KiB
GLSL
//
|
|
// Description : Array and textureless GLSL 2D/3D/4D simplex
|
|
// noise functions.
|
|
// Author : Ian McEwan, Ashima Arts.
|
|
// Maintainer : ijm
|
|
// Lastmod : 20110822 (ijm)
|
|
// License : Copyright (C) 2011 Ashima Arts. All rights reserved.
|
|
// Distributed under the MIT License. See LICENSE file.
|
|
// https://github.com/ashima/webgl-noise
|
|
//
|
|
|
|
vec4 mod289(vec4 x) {
|
|
return x - floor(x * (1.0 / 289.0)) * 289.0; }
|
|
|
|
float mod289(float x) {
|
|
return x - floor(x * (1.0 / 289.0)) * 289.0; }
|
|
|
|
vec4 permute(vec4 x) {
|
|
return mod289(((x*34.0)+1.0)*x);
|
|
}
|
|
|
|
float permute(float x) {
|
|
return mod289(((x*34.0)+1.0)*x);
|
|
}
|
|
|
|
vec4 taylorInvSqrt(vec4 r)
|
|
{
|
|
return 1.79284291400159 - 0.85373472095314 * r;
|
|
}
|
|
|
|
float taylorInvSqrt(float r)
|
|
{
|
|
return 1.79284291400159 - 0.85373472095314 * r;
|
|
}
|
|
|
|
vec4 grad4(float j, vec4 ip)
|
|
{
|
|
const vec4 ones = vec4(1.0, 1.0, 1.0, -1.0);
|
|
vec4 p,s;
|
|
|
|
p.xyz = floor( fract (vec3(j) * ip.xyz) * 7.0) * ip.z - 1.0;
|
|
p.w = 1.5 - dot(abs(p.xyz), ones.xyz);
|
|
s = vec4(lessThan(p, vec4(0.0)));
|
|
p.xyz = p.xyz + (s.xyz*2.0 - 1.0) * s.www;
|
|
|
|
return p;
|
|
}
|
|
|
|
// (sqrt(5) - 1)/4 = F4, used once below
|
|
#define F4 0.309016994374947451
|
|
|
|
float snoise(vec4 v)
|
|
{
|
|
const vec4 C = vec4( 0.138196601125011, // (5 - sqrt(5))/20 G4
|
|
0.276393202250021, // 2 * G4
|
|
0.414589803375032, // 3 * G4
|
|
-0.447213595499958); // -1 + 4 * G4
|
|
|
|
// First corner
|
|
vec4 i = floor(v + dot(v, vec4(F4)) );
|
|
vec4 x0 = v - i + dot(i, C.xxxx);
|
|
|
|
// Other corners
|
|
|
|
// Rank sorting originally contributed by Bill Licea-Kane, AMD (formerly ATI)
|
|
vec4 i0;
|
|
vec3 isX = step( x0.yzw, x0.xxx );
|
|
vec3 isYZ = step( x0.zww, x0.yyz );
|
|
// i0.x = dot( isX, vec3( 1.0 ) );
|
|
i0.x = isX.x + isX.y + isX.z;
|
|
i0.yzw = 1.0 - isX;
|
|
// i0.y += dot( isYZ.xy, vec2( 1.0 ) );
|
|
i0.y += isYZ.x + isYZ.y;
|
|
i0.zw += 1.0 - isYZ.xy;
|
|
i0.z += isYZ.z;
|
|
i0.w += 1.0 - isYZ.z;
|
|
|
|
// i0 now contains the unique values 0,1,2,3 in each channel
|
|
vec4 i3 = clamp( i0, 0.0, 1.0 );
|
|
vec4 i2 = clamp( i0-1.0, 0.0, 1.0 );
|
|
vec4 i1 = clamp( i0-2.0, 0.0, 1.0 );
|
|
|
|
// x0 = x0 - 0.0 + 0.0 * C.xxxx
|
|
// x1 = x0 - i1 + 1.0 * C.xxxx
|
|
// x2 = x0 - i2 + 2.0 * C.xxxx
|
|
// x3 = x0 - i3 + 3.0 * C.xxxx
|
|
// x4 = x0 - 1.0 + 4.0 * C.xxxx
|
|
vec4 x1 = x0 - i1 + C.xxxx;
|
|
vec4 x2 = x0 - i2 + C.yyyy;
|
|
vec4 x3 = x0 - i3 + C.zzzz;
|
|
vec4 x4 = x0 + C.wwww;
|
|
|
|
// Permutations
|
|
i = mod289(i);
|
|
float j0 = permute( permute( permute( permute(i.w) + i.z) + i.y) + i.x);
|
|
vec4 j1 = permute( permute( permute( permute (
|
|
i.w + vec4(i1.w, i2.w, i3.w, 1.0 ))
|
|
+ i.z + vec4(i1.z, i2.z, i3.z, 1.0 ))
|
|
+ i.y + vec4(i1.y, i2.y, i3.y, 1.0 ))
|
|
+ i.x + vec4(i1.x, i2.x, i3.x, 1.0 ));
|
|
|
|
// Gradients: 7x7x6 points over a cube, mapped onto a 4-cross polytope
|
|
// 7*7*6 = 294, which is close to the ring size 17*17 = 289.
|
|
vec4 ip = vec4(1.0/294.0, 1.0/49.0, 1.0/7.0, 0.0) ;
|
|
|
|
vec4 p0 = grad4(j0, ip);
|
|
vec4 p1 = grad4(j1.x, ip);
|
|
vec4 p2 = grad4(j1.y, ip);
|
|
vec4 p3 = grad4(j1.z, ip);
|
|
vec4 p4 = grad4(j1.w, ip);
|
|
|
|
// Normalise gradients
|
|
vec4 norm = taylorInvSqrt(vec4(dot(p0,p0), dot(p1,p1), dot(p2, p2), dot(p3,p3)));
|
|
p0 *= norm.x;
|
|
p1 *= norm.y;
|
|
p2 *= norm.z;
|
|
p3 *= norm.w;
|
|
p4 *= taylorInvSqrt(dot(p4,p4));
|
|
|
|
// Mix contributions from the five corners
|
|
vec3 m0 = max(0.6 - vec3(dot(x0,x0), dot(x1,x1), dot(x2,x2)), 0.0);
|
|
vec2 m1 = max(0.6 - vec2(dot(x3,x3), dot(x4,x4) ), 0.0);
|
|
m0 = m0 * m0;
|
|
m1 = m1 * m1;
|
|
return 49.0 * ( dot(m0*m0, vec3( dot( p0, x0 ), dot( p1, x1 ), dot( p2, x2 )))
|
|
+ dot(m1*m1, vec2( dot( p3, x3 ), dot( p4, x4 ) ) ) ) ;
|
|
|
|
}
|