also i did look into 3dnoise functions as suggested, i found this one which gens 3d noise from a 2d source quite cool some of the effects you can get out of the shader thou not really looking like fire, this one moves at high speed, a fire pinapple me thinks
the modified shader is below, i found a DDS plugin for photoshop and saved it as a 2d tga for the permTexture, u can get some crazy effects depending upon what noise pic u feed it
Code: Select all
uniform float time;
uniform float sideFade;
uniform float sideFadeSharpness;
uniform float wobbleScale;
uniform float burnSpeed;
uniform float randomnessRate;
uniform float yFade;
uniform float xScale;
uniform float yScale;
uniform sampler2D Flame;
varying vec2 vTexCoord;
float saturate(float inValue)
{
return clamp(inValue, 0.0, 1.0);
}
uniform sampler2D permTexture;
#define ONE 0.00390625
#define ONEHALF 0.001953125
float fade(float t) {
return t*t*t*(t*(t*6.0-15.0)+10.0); // Improved fade, yields C2-continuous noise
}
float genNoise3D(vec3 P)
{
vec3 Pi = ONE*floor(P)+ONEHALF; // Integer part, scaled so +1 moves one texel
// and offset 1/2 texel to sample texel centers
vec3 Pf = fract(P); // Fractional part for interpolation
// Noise contributions from (x=0, y=0), z=0 and z=1
float perm00 = texture2D(permTexture, Pi.xy).a ;
vec3 grad000 = texture2D(permTexture, vec2(perm00, Pi.z)).rgb * 4.0 - 1.0;
float n000 = dot(grad000, Pf);
vec3 grad001 = texture2D(permTexture, vec2(perm00, Pi.z + ONE)).rgb * 4.0 - 1.0;
float n001 = dot(grad001, Pf - vec3(0.0, 0.0, 1.0));
// Noise contributions from (x=0, y=1), z=0 and z=1
float perm01 = texture2D(permTexture, Pi.xy + vec2(0.0, ONE)).a ;
vec3 grad010 = texture2D(permTexture, vec2(perm01, Pi.z)).rgb * 4.0 - 1.0;
float n010 = dot(grad010, Pf - vec3(0.0, 1.0, 0.0));
vec3 grad011 = texture2D(permTexture, vec2(perm01, Pi.z + ONE)).rgb * 4.0 - 1.0;
float n011 = dot(grad011, Pf - vec3(0.0, 1.0, 1.0));
// Noise contributions from (x=1, y=0), z=0 and z=1
float perm10 = texture2D(permTexture, Pi.xy + vec2(ONE, 0.0)).a ;
vec3 grad100 = texture2D(permTexture, vec2(perm10, Pi.z)).rgb * 4.0 - 1.0;
float n100 = dot(grad100, Pf - vec3(1.0, 0.0, 0.0));
vec3 grad101 = texture2D(permTexture, vec2(perm10, Pi.z + ONE)).rgb * 4.0 - 1.0;
float n101 = dot(grad101, Pf - vec3(1.0, 0.0, 1.0));
// Noise contributions from (x=1, y=1), z=0 and z=1
float perm11 = texture2D(permTexture, Pi.xy + vec2(ONE, ONE)).a ;
vec3 grad110 = texture2D(permTexture, vec2(perm11, Pi.z)).rgb * 4.0 - 1.0;
float n110 = dot(grad110, Pf - vec3(1.0, 1.0, 0.0));
vec3 grad111 = texture2D(permTexture, vec2(perm11, Pi.z + ONE)).rgb * 4.0 - 1.0;
float n111 = dot(grad111, Pf - vec3(1.0, 1.0, 1.0));
// Blend contributions along x
vec4 n_x = mix(vec4(n000, n001, n010, n011),
vec4(n100, n101, n110, n111), fade(Pf.x));
// Blend contributions along y
vec2 n_xy = mix(n_x.xy, n_x.zw, fade(Pf.y));
// Blend contributions along z
float n_xyz = mix(n_xy.x, n_xy.y, fade(Pf.z));
// We're done, return the final noise value.
return n_xyz;
}
void main(void)
{
// Wobble for the noise to get a more realistic appearance
float wobbX = 2.0 * cos(6.0 * vTexCoord.x + time);
float wobbY = 7.0 * (1.0 - vTexCoord.y) * (1.0 - vTexCoord.y);
float wobble = sin(time + wobbX + wobbY);
vec3 coord;
// Wobble more in the flames than at the base
coord.x = xScale * vTexCoord.x + wobbleScale * (vTexCoord.y + 1.0) * wobble;
// Create an upwards movement
coord.y = yScale * vTexCoord.y - burnSpeed * time;
// Move in Z to get some randomness
coord.z = randomnessRate * time;
//float noisy = texture3D(Noise, coord).x;
float noisy = genNoise3D(coord);
// Define the shape of the fire
float t = sideFadeSharpness * (1.0 - sideFade * vTexCoord.x * vTexCoord.x);
// Get the color out of it all
float heat = saturate(t + noisy - yFade * vTexCoord.y);
vec4 flame = texture2D(Flame, vec2(heat,0.0));
gl_FragColor = flame;
}
still only good for a mess around thou, the thing am not sure if i got right is the noise function seems to sombine xyz and return just a float rather than a vec3, the noisy variable was only interested in x
still would like 3dnoise in a texture to work though really as i really want the inferno to be perfect, also must be less bloated code, must be faster aswell as the noise is already generated and loaded in memory.
Code: Select all
/*
* 2D, 3D and 4D Perlin noise, classic and simplex, in a GLSL fragment shader.
*
* Classic noise is implemented by the functions:
* float noise(vec2 P)
* float noise(vec3 P)
* float noise(vec4 P)
*
* Simplex noise is implemented by the functions:
* float snoise(vec2 P)
* float snoise(vec3 P)
* float snoise(vec4 P)
*
* Author: Stefan Gustavson ITN-LiTH (stegu@itn.liu.se) 2004-12-05
* You may use, modify and redistribute this code free of charge,
* provided that my name and this notice appears intact.
*/
/*
* NOTE: there is a formal problem with the dependent texture lookups.
* A texture coordinate of exactly 1.0 will wrap to 0.0, so strictly speaking,
* an error occurs every 256 units of the texture domain, and the same gradient
* is used for two adjacent noise cells. One solution is to set the texture
* wrap mode to "CLAMP" and do the wrapping explicitly in GLSL with the "mod"
* operator. This could also give you noise with repetition intervals other
* than 256 without any extra cost.
* This error is not even noticeable to the eye even if you isolate the exact
* position in the domain where it occurs and know exactly what to look for.
* The noise pattern is still visually correct, so I left the bug in there.
*
* The value of classic 4D noise goes above 1.0 and below -1.0 at some
* points. Not much and only very sparsely, but it happens.
*/
/*
* "permTexture" is a 256x256 texture that is used for both the permutations
* and the 2D and 3D gradient lookup. For details, see the main C program.
* "simplexTexture" is a small look-up table to determine a simplex traversal
* order for 3D and 4D simplex noise. Details are in the C program.
* "gradTexture" is a 256x256 texture with 4D gradients, similar to
* "permTexture" but with the permutation index in the alpha component
* replaced by the w component of the 4D gradient.
* 2D classic noise uses only permTexture.
* 2D simplex noise uses permTexture and simplexTexture.
* 3D classic noise uses only permTexture.
* 3D simplex noise uses permTexture and simplexTexture.
* 4D classic noise uses permTexture and gradTexture.
* 4D simplex noise uses all three textures.
*/
uniform sampler2D permTexture;
uniform sampler1D simplexTexture;
uniform sampler2D gradTexture;
/*
* To create offsets of one texel and one half texel in the
* texture lookup, we need to know the texture image size.
*/
#define ONE 0.00390625
#define ONEHALF 0.001953125
// The numbers above are 1/256 and 0.5/256, change accordingly
// if you change the code to use another texture size.
/*
* The interpolation function. This could be a 1D texture lookup
* to get some more speed, but it's not the main part of the algorithm.
*/
float fade(float t) {
// return t*t*(3.0-2.0*t); // Old fade, yields discontinuous second derivative
return t*t*t*(t*(t*6.0-15.0)+10.0); // Improved fade, yields C2-continuous noise
}
/*
* 2D classic Perlin noise. Fast, but less useful than 3D noise.
*/
float noise(vec2 P)
{
vec2 Pi = ONE*floor(P)+ONEHALF; // Integer part, scaled and offset for texture lookup
vec2 Pf = fract(P); // Fractional part for interpolation
// Noise contribution from lower left corner
vec2 grad00 = texture2D(permTexture, Pi).rg * 4.0 - 1.0;
float n00 = dot(grad00, Pf);
// Noise contribution from lower right corner
vec2 grad10 = texture2D(permTexture, Pi + vec2(ONE, 0.0)).rg * 4.0 - 1.0;
float n10 = dot(grad10, Pf - vec2(1.0, 0.0));
// Noise contribution from upper left corner
vec2 grad01 = texture2D(permTexture, Pi + vec2(0.0, ONE)).rg * 4.0 - 1.0;
float n01 = dot(grad01, Pf - vec2(0.0, 1.0));
// Noise contribution from upper right corner
vec2 grad11 = texture2D(permTexture, Pi + vec2(ONE, ONE)).rg * 4.0 - 1.0;
float n11 = dot(grad11, Pf - vec2(1.0, 1.0));
// Blend contributions along x
vec2 n_x = mix(vec2(n00, n01), vec2(n10, n11), fade(Pf.x));
// Blend contributions along y
float n_xy = mix(n_x.x, n_x.y, fade(Pf.y));
// We're done, return the final noise value.
return n_xy;
}
/*
* 3D classic noise. Slower, but a lot more useful than 2D noise.
*/
float noise(vec3 P)
{
vec3 Pi = ONE*floor(P)+ONEHALF; // Integer part, scaled so +1 moves one texel
// and offset 1/2 texel to sample texel centers
vec3 Pf = fract(P); // Fractional part for interpolation
// Noise contributions from (x=0, y=0), z=0 and z=1
float perm00 = texture2D(permTexture, Pi.xy).a ;
vec3 grad000 = texture2D(permTexture, vec2(perm00, Pi.z)).rgb * 4.0 - 1.0;
float n000 = dot(grad000, Pf);
vec3 grad001 = texture2D(permTexture, vec2(perm00, Pi.z + ONE)).rgb * 4.0 - 1.0;
float n001 = dot(grad001, Pf - vec3(0.0, 0.0, 1.0));
// Noise contributions from (x=0, y=1), z=0 and z=1
float perm01 = texture2D(permTexture, Pi.xy + vec2(0.0, ONE)).a ;
vec3 grad010 = texture2D(permTexture, vec2(perm01, Pi.z)).rgb * 4.0 - 1.0;
float n010 = dot(grad010, Pf - vec3(0.0, 1.0, 0.0));
vec3 grad011 = texture2D(permTexture, vec2(perm01, Pi.z + ONE)).rgb * 4.0 - 1.0;
float n011 = dot(grad011, Pf - vec3(0.0, 1.0, 1.0));
// Noise contributions from (x=1, y=0), z=0 and z=1
float perm10 = texture2D(permTexture, Pi.xy + vec2(ONE, 0.0)).a ;
vec3 grad100 = texture2D(permTexture, vec2(perm10, Pi.z)).rgb * 4.0 - 1.0;
float n100 = dot(grad100, Pf - vec3(1.0, 0.0, 0.0));
vec3 grad101 = texture2D(permTexture, vec2(perm10, Pi.z + ONE)).rgb * 4.0 - 1.0;
float n101 = dot(grad101, Pf - vec3(1.0, 0.0, 1.0));
// Noise contributions from (x=1, y=1), z=0 and z=1
float perm11 = texture2D(permTexture, Pi.xy + vec2(ONE, ONE)).a ;
vec3 grad110 = texture2D(permTexture, vec2(perm11, Pi.z)).rgb * 4.0 - 1.0;
float n110 = dot(grad110, Pf - vec3(1.0, 1.0, 0.0));
vec3 grad111 = texture2D(permTexture, vec2(perm11, Pi.z + ONE)).rgb * 4.0 - 1.0;
float n111 = dot(grad111, Pf - vec3(1.0, 1.0, 1.0));
// Blend contributions along x
vec4 n_x = mix(vec4(n000, n001, n010, n011),
vec4(n100, n101, n110, n111), fade(Pf.x));
// Blend contributions along y
vec2 n_xy = mix(n_x.xy, n_x.zw, fade(Pf.y));
// Blend contributions along z
float n_xyz = mix(n_xy.x, n_xy.y, fade(Pf.z));
// We're done, return the final noise value.
return n_xyz;
}
/*
* 4D classic noise. Slow, but very useful. 4D simplex noise is a lot faster.
*
* This function performs 8 texture lookups and 16 dependent texture lookups,
* 16 dot products, 4 mix operations and a lot of additions and multiplications.
* Needless to say, it's not super fast. But it's not dead slow either.
*/
float noise(vec4 P)
{
vec4 Pi = ONE*floor(P)+ONEHALF; // Integer part, scaled so +1 moves one texel
// and offset 1/2 texel to sample texel centers
vec4 Pf = fract(P); // Fractional part for interpolation
// "n0000" is the noise contribution from (x=0, y=0, z=0, w=0), and so on
float perm00xy = texture2D(permTexture, Pi.xy).a ;
float perm00zw = texture2D(permTexture, Pi.zw).a ;
vec4 grad0000 = texture2D(gradTexture, vec2(perm00xy, perm00zw)).rgba * 4.0 -1.0;
float n0000 = dot(grad0000, Pf);
float perm01zw = texture2D(permTexture, Pi.zw + vec2(0.0, ONE)).a ;
vec4 grad0001 = texture2D(gradTexture, vec2(perm00xy, perm01zw)).rgba * 4.0 - 1.0;
float n0001 = dot(grad0001, Pf - vec4(0.0, 0.0, 0.0, 1.0));
float perm10zw = texture2D(permTexture, Pi.zw + vec2(ONE, 0.0)).a ;
vec4 grad0010 = texture2D(gradTexture, vec2(perm00xy, perm10zw)).rgba * 4.0 - 1.0;
float n0010 = dot(grad0010, Pf - vec4(0.0, 0.0, 1.0, 0.0));
float perm11zw = texture2D(permTexture, Pi.zw + vec2(ONE, ONE)).a ;
vec4 grad0011 = texture2D(gradTexture, vec2(perm00xy, perm11zw)).rgba * 4.0 - 1.0;
float n0011 = dot(grad0011, Pf - vec4(0.0, 0.0, 1.0, 1.0));
float perm01xy = texture2D(permTexture, Pi.xy + vec2(0.0, ONE)).a ;
vec4 grad0100 = texture2D(gradTexture, vec2(perm01xy, perm00zw)).rgba * 4.0 - 1.0;
float n0100 = dot(grad0100, Pf - vec4(0.0, 1.0, 0.0, 0.0));
vec4 grad0101 = texture2D(gradTexture, vec2(perm01xy, perm01zw)).rgba * 4.0 - 1.0;
float n0101 = dot(grad0101, Pf - vec4(0.0, 1.0, 0.0, 1.0));
vec4 grad0110 = texture2D(gradTexture, vec2(perm01xy, perm10zw)).rgba * 4.0 - 1.0;
float n0110 = dot(grad0110, Pf - vec4(0.0, 1.0, 1.0, 0.0));
vec4 grad0111 = texture2D(gradTexture, vec2(perm01xy, perm11zw)).rgba * 4.0 - 1.0;
float n0111 = dot(grad0111, Pf - vec4(0.0, 1.0, 1.0, 1.0));
float perm10xy = texture2D(permTexture, Pi.xy + vec2(ONE, 0.0)).a ;
vec4 grad1000 = texture2D(gradTexture, vec2(perm10xy, perm00zw)).rgba * 4.0 - 1.0;
float n1000 = dot(grad1000, Pf - vec4(1.0, 0.0, 0.0, 0.0));
vec4 grad1001 = texture2D(gradTexture, vec2(perm10xy, perm01zw)).rgba * 4.0 - 1.0;
float n1001 = dot(grad1001, Pf - vec4(1.0, 0.0, 0.0, 1.0));
vec4 grad1010 = texture2D(gradTexture, vec2(perm10xy, perm10zw)).rgba * 4.0 - 1.0;
float n1010 = dot(grad1010, Pf - vec4(1.0, 0.0, 1.0, 0.0));
vec4 grad1011 = texture2D(gradTexture, vec2(perm10xy, perm11zw)).rgba * 4.0 - 1.0;
float n1011 = dot(grad1011, Pf - vec4(1.0, 0.0, 1.0, 1.0));
float perm11xy = texture2D(permTexture, Pi.xy + vec2(ONE, ONE)).a ;
vec4 grad1100 = texture2D(gradTexture, vec2(perm11xy, perm00zw)).rgba * 4.0 - 1.0;
float n1100 = dot(grad1100, Pf - vec4(1.0, 1.0, 0.0, 0.0));
vec4 grad1101 = texture2D(gradTexture, vec2(perm11xy, perm01zw)).rgba * 4.0 - 1.0;
float n1101 = dot(grad1101, Pf - vec4(1.0, 1.0, 0.0, 1.0));
vec4 grad1110 = texture2D(gradTexture, vec2(perm11xy, perm10zw)).rgba * 4.0 - 1.0;
float n1110 = dot(grad1110, Pf - vec4(1.0, 1.0, 1.0, 0.0));
vec4 grad1111 = texture2D(gradTexture, vec2(perm11xy, perm11zw)).rgba * 4.0 - 1.0;
float n1111 = dot(grad1111, Pf - vec4(1.0, 1.0, 1.0, 1.0));
// Blend contributions along x
float fadex = fade(Pf.x);
vec4 n_x0 = mix(vec4(n0000, n0001, n0010, n0011),
vec4(n1000, n1001, n1010, n1011), fadex);
vec4 n_x1 = mix(vec4(n0100, n0101, n0110, n0111),
vec4(n1100, n1101, n1110, n1111), fadex);
// Blend contributions along y
vec4 n_xy = mix(n_x0, n_x1, fade(Pf.y));
// Blend contributions along z
vec2 n_xyz = mix(n_xy.xy, n_xy.zw, fade(Pf.z));
// Blend contributions along w
float n_xyzw = mix(n_xyz.x, n_xyz.y, fade(Pf.w));
// We're done, return the final noise value.
return n_xyzw;
}
/*
* 2D simplex noise. Somewhat slower but much better looking than classic noise.
*/
float snoise(vec2 P) {
// Skew and unskew factors are a bit hairy for 2D, so define them as constants
// This is (sqrt(3.0)-1.0)/2.0
#define F2 0.366025403784
// This is (3.0-sqrt(3.0))/6.0
#define G2 0.211324865405
// Skew the (x,y) space to determine which cell of 2 simplices we're in
float s = (P.x + P.y) * F2; // Hairy factor for 2D skewing
vec2 Pi = floor(P + s);
float t = (Pi.x + Pi.y) * G2; // Hairy factor for unskewing
vec2 P0 = Pi - t; // Unskew the cell origin back to (x,y) space
Pi = Pi * ONE + ONEHALF; // Integer part, scaled and offset for texture lookup
vec2 Pf0 = P - P0; // The x,y distances from the cell origin
// For the 2D case, the simplex shape is an equilateral triangle.
// Find out whether we are above or below the x=y diagonal to
// determine which of the two triangles we're in.
vec2 o1;
if(Pf0.x > Pf0.y) o1 = vec2(1.0, 0.0); // +x, +y traversal order
else o1 = vec2(0.0, 1.0); // +y, +x traversal order
// Noise contribution from simplex origin
vec2 grad0 = texture2D(permTexture, Pi).rg * 4.0 - 1.0;
float t0 = 0.5 - dot(Pf0, Pf0);
float n0;
if (t0 < 0.0) n0 = 0.0;
else {
t0 *= t0;
n0 = t0 * t0 * dot(grad0, Pf0);
}
// Noise contribution from middle corner
vec2 Pf1 = Pf0 - o1 + G2;
vec2 grad1 = texture2D(permTexture, Pi + o1*ONE).rg * 4.0 - 1.0;
float t1 = 0.5 - dot(Pf1, Pf1);
float n1;
if (t1 < 0.0) n1 = 0.0;
else {
t1 *= t1;
n1 = t1 * t1 * dot(grad1, Pf1);
}
// Noise contribution from last corner
vec2 Pf2 = Pf0 - vec2(1.0-2.0*G2);
vec2 grad2 = texture2D(permTexture, Pi + vec2(ONE, ONE)).rg * 4.0 - 1.0;
float t2 = 0.5 - dot(Pf2, Pf2);
float n2;
if(t2 < 0.0) n2 = 0.0;
else {
t2 *= t2;
n2 = t2 * t2 * dot(grad2, Pf2);
}
// Sum up and scale the result to cover the range [-1,1]
return 70.0 * (n0 + n1 + n2);
}
/*
* 3D simplex noise. Comparable in speed to classic noise, better looking.
*/
float snoise(vec3 P) {
// The skewing and unskewing factors are much simpler for the 3D case
#define F3 0.333333333333
#define G3 0.166666666667
// Skew the (x,y,z) space to determine which cell of 6 simplices we're in
float s = (P.x + P.y + P.z) * F3; // Factor for 3D skewing
vec3 Pi = floor(P + s);
float t = (Pi.x + Pi.y + Pi.z) * G3;
vec3 P0 = Pi - t; // Unskew the cell origin back to (x,y,z) space
Pi = Pi * ONE + ONEHALF; // Integer part, scaled and offset for texture lookup
vec3 Pf0 = P - P0; // The x,y distances from the cell origin
// For the 3D case, the simplex shape is a slightly irregular tetrahedron.
// To find out which of the six possible tetrahedra we're in, we need to
// determine the magnitude ordering of x, y and z components of Pf0.
// The method below is explained briefly in the C code. It uses a small
// 1D texture as a lookup table. The table is designed to work for both
// 3D and 4D noise, so only 8 (only 6, actually) of the 64 indices are
// used here.
float c1 = (Pf0.x > Pf0.y) ? 0.5078125 : 0.0078125; // 1/2 + 1/128
float c2 = (Pf0.x > Pf0.z) ? 0.25 : 0.0;
float c3 = (Pf0.y > Pf0.z) ? 0.125 : 0.0;
float sindex = c1 + c2 + c3;
vec3 offsets = texture1D(simplexTexture, sindex).rgb;
vec3 o1 = step(0.375, offsets);
vec3 o2 = step(0.125, offsets);
// Noise contribution from simplex origin
float perm0 = texture2D(permTexture, Pi.xy).a;
vec3 grad0 = texture2D(permTexture, vec2(perm0, Pi.z)).rgb * 4.0 - 1.0;
float t0 = 0.6 - dot(Pf0, Pf0);
float n0;
if (t0 < 0.0) n0 = 0.0;
else {
t0 *= t0;
n0 = t0 * t0 * dot(grad0, Pf0);
}
// Noise contribution from second corner
vec3 Pf1 = Pf0 - o1 + G3;
float perm1 = texture2D(permTexture, Pi.xy + o1.xy*ONE).a;
vec3 grad1 = texture2D(permTexture, vec2(perm1, Pi.z + o1.z*ONE)).rgb * 4.0 - 1.0;
float t1 = 0.6 - dot(Pf1, Pf1);
float n1;
if (t1 < 0.0) n1 = 0.0;
else {
t1 *= t1;
n1 = t1 * t1 * dot(grad1, Pf1);
}
// Noise contribution from third corner
vec3 Pf2 = Pf0 - o2 + 2.0 * G3;
float perm2 = texture2D(permTexture, Pi.xy + o2.xy*ONE).a;
vec3 grad2 = texture2D(permTexture, vec2(perm2, Pi.z + o2.z*ONE)).rgb * 4.0 - 1.0;
float t2 = 0.6 - dot(Pf2, Pf2);
float n2;
if (t2 < 0.0) n2 = 0.0;
else {
t2 *= t2;
n2 = t2 * t2 * dot(grad2, Pf2);
}
// Noise contribution from last corner
vec3 Pf3 = Pf0 - vec3(1.0-3.0*G3);
float perm3 = texture2D(permTexture, Pi.xy + vec2(ONE, ONE)).a;
vec3 grad3 = texture2D(permTexture, vec2(perm3, Pi.z + ONE)).rgb * 4.0 - 1.0;
float t3 = 0.6 - dot(Pf3, Pf3);
float n3;
if(t3 < 0.0) n3 = 0.0;
else {
t3 *= t3;
n3 = t3 * t3 * dot(grad3, Pf3);
}
// Sum up and scale the result to cover the range [-1,1]
return 32.0 * (n0 + n1 + n2 + n3);
}
/*
* 4D simplex noise. A lot faster than classic 4D noise, and better looking.
*/
float snoise(vec4 P) {
// The skewing and unskewing factors are hairy again for the 4D case
// This is (sqrt(5.0)-1.0)/4.0
#define F4 0.309016994375
// This is (5.0-sqrt(5.0))/20.0
#define G4 0.138196601125
// Skew the (x,y,z,w) space to determine which cell of 24 simplices we're in
float s = (P.x + P.y + P.z + P.w) * F4; // Factor for 4D skewing
vec4 Pi = floor(P + s);
float t = (Pi.x + Pi.y + Pi.z + Pi.w) * G4;
vec4 P0 = Pi - t; // Unskew the cell origin back to (x,y,z,w) space
Pi = Pi * ONE + ONEHALF; // Integer part, scaled and offset for texture lookup
vec4 Pf0 = P - P0; // The x,y distances from the cell origin
// For the 4D case, the simplex is a 4D shape I won't even try to describe.
// To find out which of the 24 possible simplices we're in, we need to
// determine the magnitude ordering of x, y, z and w components of Pf0.
// The method below is presented without explanation. It uses a small 1D
// texture as a lookup table. The table is designed to work for both
// 3D and 4D noise and contains 64 indices, of which only 24 are actually
// used. An extension to 5D would require a larger texture here.
float c1 = (Pf0.x > Pf0.y) ? 0.5078125 : 0.0078125; // 1/2 + 1/128
float c2 = (Pf0.x > Pf0.z) ? 0.25 : 0.0;
float c3 = (Pf0.y > Pf0.z) ? 0.125 : 0.0;
float c4 = (Pf0.x > Pf0.w) ? 0.0625 : 0.0;
float c5 = (Pf0.y > Pf0.w) ? 0.03125 : 0.0;
float c6 = (Pf0.z > Pf0.w) ? 0.015625 : 0.0;
float sindex = c1 + c2 + c3 + c4 + c5 + c6;
vec4 offsets = texture1D(simplexTexture, sindex).rgba;
vec4 o1 = step(0.625, offsets);
vec4 o2 = step(0.375, offsets);
vec4 o3 = step(0.125, offsets);
// Noise contribution from simplex origin
float perm0xy = texture2D(permTexture, Pi.xy).a;
float perm0zw = texture2D(permTexture, Pi.zw).a;
vec4 grad0 = texture2D(gradTexture, vec2(perm0xy, perm0zw)).rgba * 4.0 - 1.0;
float t0 = 0.6 - dot(Pf0, Pf0);
float n0;
if (t0 < 0.0) n0 = 0.0;
else {
t0 *= t0;
n0 = t0 * t0 * dot(grad0, Pf0);
}
// Noise contribution from second corner
vec4 Pf1 = Pf0 - o1 + G4;
o1 = o1 * ONE;
float perm1xy = texture2D(permTexture, Pi.xy + o1.xy).a;
float perm1zw = texture2D(permTexture, Pi.zw + o1.zw).a;
vec4 grad1 = texture2D(gradTexture, vec2(perm1xy, perm1zw)).rgba * 4.0 - 1.0;
float t1 = 0.6 - dot(Pf1, Pf1);
float n1;
if (t1 < 0.0) n1 = 0.0;
else {
t1 *= t1;
n1 = t1 * t1 * dot(grad1, Pf1);
}
// Noise contribution from third corner
vec4 Pf2 = Pf0 - o2 + 2.0 * G4;
o2 = o2 * ONE;
float perm2xy = texture2D(permTexture, Pi.xy + o2.xy).a;
float perm2zw = texture2D(permTexture, Pi.zw + o2.zw).a;
vec4 grad2 = texture2D(gradTexture, vec2(perm2xy, perm2zw)).rgba * 4.0 - 1.0;
float t2 = 0.6 - dot(Pf2, Pf2);
float n2;
if (t2 < 0.0) n2 = 0.0;
else {
t2 *= t2;
n2 = t2 * t2 * dot(grad2, Pf2);
}
// Noise contribution from fourth corner
vec4 Pf3 = Pf0 - o3 + 3.0 * G4;
o3 = o3 * ONE;
float perm3xy = texture2D(permTexture, Pi.xy + o3.xy).a;
float perm3zw = texture2D(permTexture, Pi.zw + o3.zw).a;
vec4 grad3 = texture2D(gradTexture, vec2(perm3xy, perm3zw)).rgba * 4.0 - 1.0;
float t3 = 0.6 - dot(Pf3, Pf3);
float n3;
if (t3 < 0.0) n3 = 0.0;
else {
t3 *= t3;
n3 = t3 * t3 * dot(grad3, Pf3);
}
// Noise contribution from last corner
vec4 Pf4 = Pf0 - vec4(1.0-4.0*G4);
float perm4xy = texture2D(permTexture, Pi.xy + vec2(ONE, ONE)).a;
float perm4zw = texture2D(permTexture, Pi.zw + vec2(ONE, ONE)).a;
vec4 grad4 = texture2D(gradTexture, vec2(perm4xy, perm4zw)).rgba * 4.0 - 1.0;
float t4 = 0.6 - dot(Pf4, Pf4);
float n4;
if(t4 < 0.0) n4 = 0.0;
else {
t4 *= t4;
n4 = t4 * t4 * dot(grad4, Pf4);
}
// Sum up and scale the result to cover the range [-1,1]
return 27.0 * (n0 + n1 + n2 + n3 + n4);
}
Theres your problem.
.