Remove carriage-return chars *ONLY*.

1 files changed, 501 insertions, 501 deletions

diff --git a/src/mesa/shader/slang/slang_library_noise.c b/src/mesa/shader/slang/slang_library_noise.c
index d0081c542a..b30bb30ce2 100644
--- a/src/mesa/shader/slang/slang_library_noise.c
+++ b/src/mesa/shader/slang/slang_library_noise.c
@@ -1,501 +1,501 @@
-/*

- * Mesa 3-D graphics library

- * Version:  6.5

- *

- * Copyright (C) 2006  Brian Paul   All Rights Reserved.

- *

- * Permission is hereby granted, free of charge, to any person obtaining a

- * copy of this software and associated documentation files (the "Software"),

- * to deal in the Software without restriction, including without limitation

- * the rights to use, copy, modify, merge, publish, distribute, sublicense,

- * and/or sell copies of the Software, and to permit persons to whom the

- * Software is furnished to do so, subject to the following conditions:

- *

- * The above copyright notice and this permission notice shall be included

- * in all copies or substantial portions of the Software.

- *

- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

- * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL

- * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN

- * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

- */

-

-/*

- * SimplexNoise1234

- * Copyright © 2003-2005, Stefan Gustavson

- *

- * Contact: stegu@itn.liu.se

- */

-

-/** \file

-    \brief C implementation of Perlin Simplex Noise over 1,2,3, and 4 dimensions.

-    \author Stefan Gustavson (stegu@itn.liu.se)

-*/

-

-/*

- * This implementation is "Simplex Noise" as presented by

- * Ken Perlin at a relatively obscure and not often cited course

- * session "Real-Time Shading" at Siggraph 2001 (before real

- * time shading actually took on), under the title "hardware noise".

- * The 3D function is numerically equivalent to his Java reference

- * code available in the PDF course notes, although I re-implemented

- * it from scratch to get more readable code. The 1D, 2D and 4D cases

- * were implemented from scratch by me from Ken Perlin's text.

- *

- * This file has no dependencies on any other file, not even its own

- * header file. The header file is made for use by external code only.

- */

-

-

-#include "imports.h"

-#include "slang_library_noise.h"

-

-#define FASTFLOOR(x) ( ((x)>0) ? ((int)x) : (((int)x)-1) )

-

-/*

- * ---------------------------------------------------------------------

- * Static data

- */

-

-/*

- * Permutation table. This is just a random jumble of all numbers 0-255,

- * repeated twice to avoid wrapping the index at 255 for each lookup.

- * This needs to be exactly the same for all instances on all platforms,

- * so it's easiest to just keep it as static explicit data.

- * This also removes the need for any initialisation of this class.

- *

- * Note that making this an int[] instead of a char[] might make the

- * code run faster on platforms with a high penalty for unaligned single

- * byte addressing. Intel x86 is generally single-byte-friendly, but

- * some other CPUs are faster with 4-aligned reads.

- * However, a char[] is smaller, which avoids cache trashing, and that

- * is probably the most important aspect on most architectures.

- * This array is accessed a *lot* by the noise functions.

- * A vector-valued noise over 3D accesses it 96 times, and a

- * float-valued 4D noise 64 times. We want this to fit in the cache!

- */

-unsigned char perm[512] = {151,160,137,91,90,15,

-  131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,

-  190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,

-  88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,

-  77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,

-  102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,

-  135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,

-  5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,

-  223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,

-  129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,

-  251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,

-  49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,

-  138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180,

-  151,160,137,91,90,15,

-  131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,

-  190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,

-  88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,

-  77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,

-  102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,

-  135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,

-  5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,

-  223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,

-  129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,

-  251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,

-  49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,

-  138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180 

-};

-

-/*

- * ---------------------------------------------------------------------

- */

-

-/*

- * Helper functions to compute gradients-dot-residualvectors (1D to 4D)

- * Note that these generate gradients of more than unit length. To make

- * a close match with the value range of classic Perlin noise, the final

- * noise values need to be rescaled to fit nicely within [-1,1].

- * (The simplex noise functions as such also have different scaling.)

- * Note also that these noise functions are the most practical and useful

- * signed version of Perlin noise. To return values according to the

- * RenderMan specification from the SL noise() and pnoise() functions,

- * the noise values need to be scaled and offset to [0,1], like this:

- * float SLnoise = (SimplexNoise1234::noise(x,y,z) + 1.0) * 0.5;

- */

-

-static float  grad1( int hash, float x ) {

-    int h = hash & 15;

-    float grad = 1.0f + (h & 7);   /* Gradient value 1.0, 2.0, ..., 8.0 */

-    if (h&8) grad = -grad;         /* Set a random sign for the gradient */

-    return ( grad * x );           /* Multiply the gradient with the distance */

-}

-

-static float  grad2( int hash, float x, float y ) {

-    int h = hash & 7;      /* Convert low 3 bits of hash code */

-    float u = h<4 ? x : y;  /* into 8 simple gradient directions, */

-    float v = h<4 ? y : x;  /* and compute the dot product with (x,y). */

-    return ((h&1)? -u : u) + ((h&2)? -2.0f*v : 2.0f*v);

-}

-

-static float  grad3( int hash, float x, float y , float z ) {

-    int h = hash & 15;     /* Convert low 4 bits of hash code into 12 simple */

-    float u = h<8 ? x : y; /* gradient directions, and compute dot product. */

-    float v = h<4 ? y : h==12||h==14 ? x : z; /* Fix repeats at h = 12 to 15 */

-    return ((h&1)? -u : u) + ((h&2)? -v : v);

-}

-

-static float  grad4( int hash, float x, float y, float z, float t ) {

-    int h = hash & 31;      /* Convert low 5 bits of hash code into 32 simple */

-    float u = h<24 ? x : y; /* gradient directions, and compute dot product. */

-    float v = h<16 ? y : z;

-    float w = h<8 ? z : t;

-    return ((h&1)? -u : u) + ((h&2)? -v : v) + ((h&4)? -w : w);

-}

-

-  /* A lookup table to traverse the simplex around a given point in 4D. */

-  /* Details can be found where this table is used, in the 4D noise method. */

-  /* TODO: This should not be required, backport it from Bill's GLSL code! */

-  static unsigned char simplex[64][4] = {

-    {0,1,2,3},{0,1,3,2},{0,0,0,0},{0,2,3,1},{0,0,0,0},{0,0,0,0},{0,0,0,0},{1,2,3,0},

-    {0,2,1,3},{0,0,0,0},{0,3,1,2},{0,3,2,1},{0,0,0,0},{0,0,0,0},{0,0,0,0},{1,3,2,0},

-    {0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},

-    {1,2,0,3},{0,0,0,0},{1,3,0,2},{0,0,0,0},{0,0,0,0},{0,0,0,0},{2,3,0,1},{2,3,1,0},

-    {1,0,2,3},{1,0,3,2},{0,0,0,0},{0,0,0,0},{0,0,0,0},{2,0,3,1},{0,0,0,0},{2,1,3,0},

-    {0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},

-    {2,0,1,3},{0,0,0,0},{0,0,0,0},{0,0,0,0},{3,0,1,2},{3,0,2,1},{0,0,0,0},{3,1,2,0},

-    {2,1,0,3},{0,0,0,0},{0,0,0,0},{0,0,0,0},{3,1,0,2},{0,0,0,0},{3,2,0,1},{3,2,1,0}};

-

-/* 1D simplex noise */

-GLfloat _slang_library_noise1 (GLfloat x)

-{

-  int i0 = FASTFLOOR(x);

-  int i1 = i0 + 1;

-  float x0 = x - i0;

-  float x1 = x0 - 1.0f;

-  float t1 = 1.0f - x1*x1;

-  float n0, n1;

-

-  float t0 = 1.0f - x0*x0;

-/*  if(t0 < 0.0f) t0 = 0.0f; // this never happens for the 1D case */

-  t0 *= t0;

-  n0 = t0 * t0 * grad1(perm[i0 & 0xff], x0);

-

-/*  if(t1 < 0.0f) t1 = 0.0f; // this never happens for the 1D case */

-  t1 *= t1;

-  n1 = t1 * t1 * grad1(perm[i1 & 0xff], x1);

-  /* The maximum value of this noise is 8*(3/4)^4 = 2.53125 */

-  /* A factor of 0.395 would scale to fit exactly within [-1,1], but */

-  /* we want to match PRMan's 1D noise, so we scale it down some more. */

-  return 0.25f * (n0 + n1);

-}

-

-/* 2D simplex noise */

-GLfloat _slang_library_noise2 (GLfloat x, GLfloat y)

-{

-#define F2 0.366025403f /* F2 = 0.5*(sqrt(3.0)-1.0) */

-#define G2 0.211324865f /* G2 = (3.0-Math.sqrt(3.0))/6.0 */

-

-    float n0, n1, n2; /* Noise contributions from the three corners */

-

-    /* Skew the input space to determine which simplex cell we're in */

-    float s = (x+y)*F2; /* Hairy factor for 2D */

-    float xs = x + s;

-    float ys = y + s;

-    int i = FASTFLOOR(xs);

-    int j = FASTFLOOR(ys);

-

-    float t = (float)(i+j)*G2;

-    float X0 = i-t; /* Unskew the cell origin back to (x,y) space */

-    float Y0 = j-t;

-    float x0 = x-X0; /* The x,y distances from the cell origin */

-    float y0 = y-Y0;

-

-    float x1, y1, x2, y2;

-    int ii, jj;

-    float t0, t1, t2;

-

-    /* For the 2D case, the simplex shape is an equilateral triangle. */

-    /* Determine which simplex we are in. */

-    int i1, j1; /* Offsets for second (middle) corner of simplex in (i,j) coords */

-    if(x0>y0) {i1=1; j1=0;} /* lower triangle, XY order: (0,0)->(1,0)->(1,1) */

-    else {i1=0; j1=1;}      /* upper triangle, YX order: (0,0)->(0,1)->(1,1) */

-

-    /* A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and */

-    /* a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where */

-    /* c = (3-sqrt(3))/6 */

-

-    x1 = x0 - i1 + G2; /* Offsets for middle corner in (x,y) unskewed coords */

-    y1 = y0 - j1 + G2;

-    x2 = x0 - 1.0f + 2.0f * G2; /* Offsets for last corner in (x,y) unskewed coords */

-    y2 = y0 - 1.0f + 2.0f * G2;

-

-    /* Wrap the integer indices at 256, to avoid indexing perm[] out of bounds */

-    ii = i % 256;

-    jj = j % 256;

-

-    /* Calculate the contribution from the three corners */

-    t0 = 0.5f - x0*x0-y0*y0;

-    if(t0 < 0.0f) n0 = 0.0f;

-    else {

-      t0 *= t0;

-      n0 = t0 * t0 * grad2(perm[ii+perm[jj]], x0, y0); 

-    }

-

-    t1 = 0.5f - x1*x1-y1*y1;

-    if(t1 < 0.0f) n1 = 0.0f;

-    else {

-      t1 *= t1;

-      n1 = t1 * t1 * grad2(perm[ii+i1+perm[jj+j1]], x1, y1);

-    }

-

-    t2 = 0.5f - x2*x2-y2*y2;

-    if(t2 < 0.0f) n2 = 0.0f;

-    else {

-      t2 *= t2;

-      n2 = t2 * t2 * grad2(perm[ii+1+perm[jj+1]], x2, y2);

-    }

-

-    /* Add contributions from each corner to get the final noise value. */

-    /* The result is scaled to return values in the interval [-1,1]. */

-    return 40.0f * (n0 + n1 + n2); /* TODO: The scale factor is preliminary! */

-}

-

-/* 3D simplex noise */

-GLfloat _slang_library_noise3 (GLfloat x, GLfloat y, GLfloat z)

-{

-/* Simple skewing factors for the 3D case */

-#define F3 0.333333333f

-#define G3 0.166666667f

-

-    float n0, n1, n2, n3; /* Noise contributions from the four corners */

-

-    /* Skew the input space to determine which simplex cell we're in */

-    float s = (x+y+z)*F3; /* Very nice and simple skew factor for 3D */

-    float xs = x+s;

-    float ys = y+s;

-    float zs = z+s;

-    int i = FASTFLOOR(xs);

-    int j = FASTFLOOR(ys);

-    int k = FASTFLOOR(zs);

-

-    float t = (float)(i+j+k)*G3; 

-    float X0 = i-t; /* Unskew the cell origin back to (x,y,z) space */

-    float Y0 = j-t;

-    float Z0 = k-t;

-    float x0 = x-X0; /* The x,y,z distances from the cell origin */

-    float y0 = y-Y0;

-    float z0 = z-Z0;

-

-    float x1, y1, z1, x2, y2, z2, x3, y3, z3;

-    int ii, jj, kk;

-    float t0, t1, t2, t3;

-

-    /* For the 3D case, the simplex shape is a slightly irregular tetrahedron. */

-    /* Determine which simplex we are in. */

-    int i1, j1, k1; /* Offsets for second corner of simplex in (i,j,k) coords */

-    int i2, j2, k2; /* Offsets for third corner of simplex in (i,j,k) coords */

-

-/* This code would benefit from a backport from the GLSL version! */

-    if(x0>=y0) {

-      if(y0>=z0)

-        { i1=1; j1=0; k1=0; i2=1; j2=1; k2=0; } /* X Y Z order */

-        else if(x0>=z0) { i1=1; j1=0; k1=0; i2=1; j2=0; k2=1; } /* X Z Y order */

-        else { i1=0; j1=0; k1=1; i2=1; j2=0; k2=1; } /* Z X Y order */

-      }

-    else { /* x0<y0 */

-      if(y0<z0) { i1=0; j1=0; k1=1; i2=0; j2=1; k2=1; } /* Z Y X order */

-      else if(x0<z0) { i1=0; j1=1; k1=0; i2=0; j2=1; k2=1; } /* Y Z X order */

-      else { i1=0; j1=1; k1=0; i2=1; j2=1; k2=0; } /* Y X Z order */

-    }

-

-    /* A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z), */

-    /* a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and */

-    /* a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where */

-    /* c = 1/6. */

-

-    x1 = x0 - i1 + G3; /* Offsets for second corner in (x,y,z) coords */

-    y1 = y0 - j1 + G3;

-    z1 = z0 - k1 + G3;

-    x2 = x0 - i2 + 2.0f*G3; /* Offsets for third corner in (x,y,z) coords */

-    y2 = y0 - j2 + 2.0f*G3;

-    z2 = z0 - k2 + 2.0f*G3;

-    x3 = x0 - 1.0f + 3.0f*G3; /* Offsets for last corner in (x,y,z) coords */

-    y3 = y0 - 1.0f + 3.0f*G3;

-    z3 = z0 - 1.0f + 3.0f*G3;

-

-    /* Wrap the integer indices at 256, to avoid indexing perm[] out of bounds */

-    ii = i % 256;

-    jj = j % 256;

-    kk = k % 256;

-

-    /* Calculate the contribution from the four corners */

-    t0 = 0.6f - x0*x0 - y0*y0 - z0*z0;

-    if(t0 < 0.0f) n0 = 0.0f;

-    else {

-      t0 *= t0;

-      n0 = t0 * t0 * grad3(perm[ii+perm[jj+perm[kk]]], x0, y0, z0);

-    }

-

-    t1 = 0.6f - x1*x1 - y1*y1 - z1*z1;

-    if(t1 < 0.0f) n1 = 0.0f;

-    else {

-      t1 *= t1;

-      n1 = t1 * t1 * grad3(perm[ii+i1+perm[jj+j1+perm[kk+k1]]], x1, y1, z1);

-    }

-

-    t2 = 0.6f - x2*x2 - y2*y2 - z2*z2;

-    if(t2 < 0.0f) n2 = 0.0f;

-    else {

-      t2 *= t2;

-      n2 = t2 * t2 * grad3(perm[ii+i2+perm[jj+j2+perm[kk+k2]]], x2, y2, z2);

-    }

-

-    t3 = 0.6f - x3*x3 - y3*y3 - z3*z3;

-    if(t3<0.0f) n3 = 0.0f;

-    else {

-      t3 *= t3;

-      n3 = t3 * t3 * grad3(perm[ii+1+perm[jj+1+perm[kk+1]]], x3, y3, z3);

-    }

-

-    /* Add contributions from each corner to get the final noise value. */

-    /* The result is scaled to stay just inside [-1,1] */

-    return 32.0f * (n0 + n1 + n2 + n3); /* TODO: The scale factor is preliminary! */

-}

-

-/* 4D simplex noise */

-GLfloat _slang_library_noise4 (GLfloat x, GLfloat y, GLfloat z, GLfloat w)

-{

-  /* The skewing and unskewing factors are hairy again for the 4D case */

-#define F4 0.309016994f /* F4 = (Math.sqrt(5.0)-1.0)/4.0 */

-#define G4 0.138196601f /* G4 = (5.0-Math.sqrt(5.0))/20.0 */

-

-    float n0, n1, n2, n3, n4; /* Noise contributions from the five corners */

-

-    /* Skew the (x,y,z,w) space to determine which cell of 24 simplices we're in */

-    float s = (x + y + z + w) * F4; /* Factor for 4D skewing */

-    float xs = x + s;

-    float ys = y + s;

-    float zs = z + s;

-    float ws = w + s;

-    int i = FASTFLOOR(xs);

-    int j = FASTFLOOR(ys);

-    int k = FASTFLOOR(zs);

-    int l = FASTFLOOR(ws);

-

-    float t = (i + j + k + l) * G4; /* Factor for 4D unskewing */

-    float X0 = i - t; /* Unskew the cell origin back to (x,y,z,w) space */

-    float Y0 = j - t;

-    float Z0 = k - t;

-    float W0 = l - t;

-

-    float x0 = x - X0;  /* The x,y,z,w distances from the cell origin */

-    float y0 = y - Y0;

-    float z0 = z - Z0;

-    float w0 = w - W0;

-

-    /* 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 x0, y0, z0 and w0. */

-    /* The method below is a good way of finding the ordering of x,y,z,w and */

-    /* then find the correct traversal order for the simplex we’re in. */

-    /* First, six pair-wise comparisons are performed between each possible pair */

-    /* of the four coordinates, and the results are used to add up binary bits */

-    /* for an integer index. */

-    int c1 = (x0 > y0) ? 32 : 0;

-    int c2 = (x0 > z0) ? 16 : 0;

-    int c3 = (y0 > z0) ? 8 : 0;

-    int c4 = (x0 > w0) ? 4 : 0;

-    int c5 = (y0 > w0) ? 2 : 0;

-    int c6 = (z0 > w0) ? 1 : 0;

-    int c = c1 + c2 + c3 + c4 + c5 + c6;

-

-    int i1, j1, k1, l1; /* The integer offsets for the second simplex corner */

-    int i2, j2, k2, l2; /* The integer offsets for the third simplex corner */

-    int i3, j3, k3, l3; /* The integer offsets for the fourth simplex corner */

-

-    float x1, y1, z1, w1, x2, y2, z2, w2, x3, y3, z3, w3, x4, y4, z4, w4;

-    int ii, jj, kk, ll;

-    float t0, t1, t2, t3, t4;

-

-    /* simplex[c] is a 4-vector with the numbers 0, 1, 2 and 3 in some order. */

-    /* Many values of c will never occur, since e.g. x>y>z>w makes x<z, y<w and x<w */

-    /* impossible. Only the 24 indices which have non-zero entries make any sense. */

-    /* We use a thresholding to set the coordinates in turn from the largest magnitude. */

-    /* The number 3 in the "simplex" array is at the position of the largest coordinate. */

-    i1 = simplex[c][0]>=3 ? 1 : 0;

-    j1 = simplex[c][1]>=3 ? 1 : 0;

-    k1 = simplex[c][2]>=3 ? 1 : 0;

-    l1 = simplex[c][3]>=3 ? 1 : 0;

-    /* The number 2 in the "simplex" array is at the second largest coordinate. */

-    i2 = simplex[c][0]>=2 ? 1 : 0;

-    j2 = simplex[c][1]>=2 ? 1 : 0;

-    k2 = simplex[c][2]>=2 ? 1 : 0;

-    l2 = simplex[c][3]>=2 ? 1 : 0;

-    /* The number 1 in the "simplex" array is at the second smallest coordinate. */

-    i3 = simplex[c][0]>=1 ? 1 : 0;

-    j3 = simplex[c][1]>=1 ? 1 : 0;

-    k3 = simplex[c][2]>=1 ? 1 : 0;

-    l3 = simplex[c][3]>=1 ? 1 : 0;

-    /* The fifth corner has all coordinate offsets = 1, so no need to look that up. */

-

-    x1 = x0 - i1 + G4; /* Offsets for second corner in (x,y,z,w) coords */

-    y1 = y0 - j1 + G4;

-    z1 = z0 - k1 + G4;

-    w1 = w0 - l1 + G4;

-    x2 = x0 - i2 + 2.0f*G4; /* Offsets for third corner in (x,y,z,w) coords */

-    y2 = y0 - j2 + 2.0f*G4;

-    z2 = z0 - k2 + 2.0f*G4;

-    w2 = w0 - l2 + 2.0f*G4;

-    x3 = x0 - i3 + 3.0f*G4; /* Offsets for fourth corner in (x,y,z,w) coords */

-    y3 = y0 - j3 + 3.0f*G4;

-    z3 = z0 - k3 + 3.0f*G4;

-    w3 = w0 - l3 + 3.0f*G4;

-    x4 = x0 - 1.0f + 4.0f*G4; /* Offsets for last corner in (x,y,z,w) coords */

-    y4 = y0 - 1.0f + 4.0f*G4;

-    z4 = z0 - 1.0f + 4.0f*G4;

-    w4 = w0 - 1.0f + 4.0f*G4;

-

-    /* Wrap the integer indices at 256, to avoid indexing perm[] out of bounds */

-    ii = i % 256;

-    jj = j % 256;

-    kk = k % 256;

-    ll = l % 256;

-

-    /* Calculate the contribution from the five corners */

-    t0 = 0.6f - x0*x0 - y0*y0 - z0*z0 - w0*w0;

-    if(t0 < 0.0f) n0 = 0.0f;

-    else {

-      t0 *= t0;

-      n0 = t0 * t0 * grad4(perm[ii+perm[jj+perm[kk+perm[ll]]]], x0, y0, z0, w0);

-    }

-

-   t1 = 0.6f - x1*x1 - y1*y1 - z1*z1 - w1*w1;

-    if(t1 < 0.0f) n1 = 0.0f;

-    else {

-      t1 *= t1;

-      n1 = t1 * t1 * grad4(perm[ii+i1+perm[jj+j1+perm[kk+k1+perm[ll+l1]]]], x1, y1, z1, w1);

-    }

-

-   t2 = 0.6f - x2*x2 - y2*y2 - z2*z2 - w2*w2;

-    if(t2 < 0.0f) n2 = 0.0f;

-    else {

-      t2 *= t2;

-      n2 = t2 * t2 * grad4(perm[ii+i2+perm[jj+j2+perm[kk+k2+perm[ll+l2]]]], x2, y2, z2, w2);

-    }

-

-   t3 = 0.6f - x3*x3 - y3*y3 - z3*z3 - w3*w3;

-    if(t3 < 0.0f) n3 = 0.0f;

-    else {

-      t3 *= t3;

-      n3 = t3 * t3 * grad4(perm[ii+i3+perm[jj+j3+perm[kk+k3+perm[ll+l3]]]], x3, y3, z3, w3);

-    }

-

-   t4 = 0.6f - x4*x4 - y4*y4 - z4*z4 - w4*w4;

-    if(t4 < 0.0f) n4 = 0.0f;

-    else {

-      t4 *= t4;

-      n4 = t4 * t4 * grad4(perm[ii+1+perm[jj+1+perm[kk+1+perm[ll+1]]]], x4, y4, z4, w4);

-    }

-

-    /* Sum up and scale the result to cover the range [-1,1] */

-    return 27.0f * (n0 + n1 + n2 + n3 + n4); /* TODO: The scale factor is preliminary! */

-}

-

+/*
+ * Mesa 3-D graphics library
+ * Version:  6.5
+ *
+ * Copyright (C) 2006  Brian Paul   All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/*
+ * SimplexNoise1234
+ * Copyright © 2003-2005, Stefan Gustavson
+ *
+ * Contact: stegu@itn.liu.se
+ */
+
+/** \file
+    \brief C implementation of Perlin Simplex Noise over 1,2,3, and 4 dimensions.
+    \author Stefan Gustavson (stegu@itn.liu.se)
+*/
+
+/*
+ * This implementation is "Simplex Noise" as presented by
+ * Ken Perlin at a relatively obscure and not often cited course
+ * session "Real-Time Shading" at Siggraph 2001 (before real
+ * time shading actually took on), under the title "hardware noise".
+ * The 3D function is numerically equivalent to his Java reference
+ * code available in the PDF course notes, although I re-implemented
+ * it from scratch to get more readable code. The 1D, 2D and 4D cases
+ * were implemented from scratch by me from Ken Perlin's text.
+ *
+ * This file has no dependencies on any other file, not even its own
+ * header file. The header file is made for use by external code only.
+ */
+
+
+#include "imports.h"
+#include "slang_library_noise.h"
+
+#define FASTFLOOR(x) ( ((x)>0) ? ((int)x) : (((int)x)-1) )
+
+/*
+ * ---------------------------------------------------------------------
+ * Static data
+ */
+
+/*
+ * Permutation table. This is just a random jumble of all numbers 0-255,
+ * repeated twice to avoid wrapping the index at 255 for each lookup.
+ * This needs to be exactly the same for all instances on all platforms,
+ * so it's easiest to just keep it as static explicit data.
+ * This also removes the need for any initialisation of this class.
+ *
+ * Note that making this an int[] instead of a char[] might make the
+ * code run faster on platforms with a high penalty for unaligned single
+ * byte addressing. Intel x86 is generally single-byte-friendly, but
+ * some other CPUs are faster with 4-aligned reads.
+ * However, a char[] is smaller, which avoids cache trashing, and that
+ * is probably the most important aspect on most architectures.
+ * This array is accessed a *lot* by the noise functions.
+ * A vector-valued noise over 3D accesses it 96 times, and a
+ * float-valued 4D noise 64 times. We want this to fit in the cache!
+ */
+unsigned char perm[512] = {151,160,137,91,90,15,
+  131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
+  190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
+  88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
+  77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
+  102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
+  135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
+  5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
+  223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
+  129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
+  251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
+  49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
+  138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180,
+  151,160,137,91,90,15,
+  131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
+  190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
+  88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
+  77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
+  102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
+  135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
+  5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
+  223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
+  129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
+  251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
+  49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
+  138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180 
+};
+
+/*
+ * ---------------------------------------------------------------------
+ */
+
+/*
+ * Helper functions to compute gradients-dot-residualvectors (1D to 4D)
+ * Note that these generate gradients of more than unit length. To make
+ * a close match with the value range of classic Perlin noise, the final
+ * noise values need to be rescaled to fit nicely within [-1,1].
+ * (The simplex noise functions as such also have different scaling.)
+ * Note also that these noise functions are the most practical and useful
+ * signed version of Perlin noise. To return values according to the
+ * RenderMan specification from the SL noise() and pnoise() functions,
+ * the noise values need to be scaled and offset to [0,1], like this:
+ * float SLnoise = (SimplexNoise1234::noise(x,y,z) + 1.0) * 0.5;
+ */
+
+static float  grad1( int hash, float x ) {
+    int h = hash & 15;
+    float grad = 1.0f + (h & 7);   /* Gradient value 1.0, 2.0, ..., 8.0 */
+    if (h&8) grad = -grad;         /* Set a random sign for the gradient */
+    return ( grad * x );           /* Multiply the gradient with the distance */
+}
+
+static float  grad2( int hash, float x, float y ) {
+    int h = hash & 7;      /* Convert low 3 bits of hash code */
+    float u = h<4 ? x : y;  /* into 8 simple gradient directions, */
+    float v = h<4 ? y : x;  /* and compute the dot product with (x,y). */
+    return ((h&1)? -u : u) + ((h&2)? -2.0f*v : 2.0f*v);
+}
+
+static float  grad3( int hash, float x, float y , float z ) {
+    int h = hash & 15;     /* Convert low 4 bits of hash code into 12 simple */
+    float u = h<8 ? x : y; /* gradient directions, and compute dot product. */
+    float v = h<4 ? y : h==12||h==14 ? x : z; /* Fix repeats at h = 12 to 15 */
+    return ((h&1)? -u : u) + ((h&2)? -v : v);
+}
+
+static float  grad4( int hash, float x, float y, float z, float t ) {
+    int h = hash & 31;      /* Convert low 5 bits of hash code into 32 simple */
+    float u = h<24 ? x : y; /* gradient directions, and compute dot product. */
+    float v = h<16 ? y : z;
+    float w = h<8 ? z : t;
+    return ((h&1)? -u : u) + ((h&2)? -v : v) + ((h&4)? -w : w);
+}
+
+  /* A lookup table to traverse the simplex around a given point in 4D. */
+  /* Details can be found where this table is used, in the 4D noise method. */
+  /* TODO: This should not be required, backport it from Bill's GLSL code! */
+  static unsigned char simplex[64][4] = {
+    {0,1,2,3},{0,1,3,2},{0,0,0,0},{0,2,3,1},{0,0,0,0},{0,0,0,0},{0,0,0,0},{1,2,3,0},
+    {0,2,1,3},{0,0,0,0},{0,3,1,2},{0,3,2,1},{0,0,0,0},{0,0,0,0},{0,0,0,0},{1,3,2,0},
+    {0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},
+    {1,2,0,3},{0,0,0,0},{1,3,0,2},{0,0,0,0},{0,0,0,0},{0,0,0,0},{2,3,0,1},{2,3,1,0},
+    {1,0,2,3},{1,0,3,2},{0,0,0,0},{0,0,0,0},{0,0,0,0},{2,0,3,1},{0,0,0,0},{2,1,3,0},
+    {0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},
+    {2,0,1,3},{0,0,0,0},{0,0,0,0},{0,0,0,0},{3,0,1,2},{3,0,2,1},{0,0,0,0},{3,1,2,0},
+    {2,1,0,3},{0,0,0,0},{0,0,0,0},{0,0,0,0},{3,1,0,2},{0,0,0,0},{3,2,0,1},{3,2,1,0}};
+
+/* 1D simplex noise */
+GLfloat _slang_library_noise1 (GLfloat x)
+{
+  int i0 = FASTFLOOR(x);
+  int i1 = i0 + 1;
+  float x0 = x - i0;
+  float x1 = x0 - 1.0f;
+  float t1 = 1.0f - x1*x1;
+  float n0, n1;
+
+  float t0 = 1.0f - x0*x0;
+/*  if(t0 < 0.0f) t0 = 0.0f; // this never happens for the 1D case */
+  t0 *= t0;
+  n0 = t0 * t0 * grad1(perm[i0 & 0xff], x0);
+
+/*  if(t1 < 0.0f) t1 = 0.0f; // this never happens for the 1D case */
+  t1 *= t1;
+  n1 = t1 * t1 * grad1(perm[i1 & 0xff], x1);
+  /* The maximum value of this noise is 8*(3/4)^4 = 2.53125 */
+  /* A factor of 0.395 would scale to fit exactly within [-1,1], but */
+  /* we want to match PRMan's 1D noise, so we scale it down some more. */
+  return 0.25f * (n0 + n1);
+}
+
+/* 2D simplex noise */
+GLfloat _slang_library_noise2 (GLfloat x, GLfloat y)
+{
+#define F2 0.366025403f /* F2 = 0.5*(sqrt(3.0)-1.0) */
+#define G2 0.211324865f /* G2 = (3.0-Math.sqrt(3.0))/6.0 */
+
+    float n0, n1, n2; /* Noise contributions from the three corners */
+
+    /* Skew the input space to determine which simplex cell we're in */
+    float s = (x+y)*F2; /* Hairy factor for 2D */
+    float xs = x + s;
+    float ys = y + s;
+    int i = FASTFLOOR(xs);
+    int j = FASTFLOOR(ys);
+
+    float t = (float)(i+j)*G2;
+    float X0 = i-t; /* Unskew the cell origin back to (x,y) space */
+    float Y0 = j-t;
+    float x0 = x-X0; /* The x,y distances from the cell origin */
+    float y0 = y-Y0;
+
+    float x1, y1, x2, y2;
+    int ii, jj;
+    float t0, t1, t2;
+
+    /* For the 2D case, the simplex shape is an equilateral triangle. */
+    /* Determine which simplex we are in. */
+    int i1, j1; /* Offsets for second (middle) corner of simplex in (i,j) coords */
+    if(x0>y0) {i1=1; j1=0;} /* lower triangle, XY order: (0,0)->(1,0)->(1,1) */
+    else {i1=0; j1=1;}      /* upper triangle, YX order: (0,0)->(0,1)->(1,1) */
+
+    /* A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and */
+    /* a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where */
+    /* c = (3-sqrt(3))/6 */
+
+    x1 = x0 - i1 + G2; /* Offsets for middle corner in (x,y) unskewed coords */
+    y1 = y0 - j1 + G2;
+    x2 = x0 - 1.0f + 2.0f * G2; /* Offsets for last corner in (x,y) unskewed coords */
+    y2 = y0 - 1.0f + 2.0f * G2;
+
+    /* Wrap the integer indices at 256, to avoid indexing perm[] out of bounds */
+    ii = i % 256;
+    jj = j % 256;
+
+    /* Calculate the contribution from the three corners */
+    t0 = 0.5f - x0*x0-y0*y0;
+    if(t0 < 0.0f) n0 = 0.0f;
+    else {
+      t0 *= t0;
+      n0 = t0 * t0 * grad2(perm[ii+perm[jj]], x0, y0); 
+    }
+
+    t1 = 0.5f - x1*x1-y1*y1;
+    if(t1 < 0.0f) n1 = 0.0f;
+    else {
+      t1 *= t1;
+      n1 = t1 * t1 * grad2(perm[ii+i1+perm[jj+j1]], x1, y1);
+    }
+
+    t2 = 0.5f - x2*x2-y2*y2;
+    if(t2 < 0.0f) n2 = 0.0f;
+    else {
+      t2 *= t2;
+      n2 = t2 * t2 * grad2(perm[ii+1+perm[jj+1]], x2, y2);
+    }
+
+    /* Add contributions from each corner to get the final noise value. */
+    /* The result is scaled to return values in the interval [-1,1]. */
+    return 40.0f * (n0 + n1 + n2); /* TODO: The scale factor is preliminary! */
+}
+
+/* 3D simplex noise */
+GLfloat _slang_library_noise3 (GLfloat x, GLfloat y, GLfloat z)
+{
+/* Simple skewing factors for the 3D case */
+#define F3 0.333333333f
+#define G3 0.166666667f
+
+    float n0, n1, n2, n3; /* Noise contributions from the four corners */
+
+    /* Skew the input space to determine which simplex cell we're in */
+    float s = (x+y+z)*F3; /* Very nice and simple skew factor for 3D */
+    float xs = x+s;
+    float ys = y+s;
+    float zs = z+s;
+    int i = FASTFLOOR(xs);
+    int j = FASTFLOOR(ys);
+    int k = FASTFLOOR(zs);
+
+    float t = (float)(i+j+k)*G3; 
+    float X0 = i-t; /* Unskew the cell origin back to (x,y,z) space */
+    float Y0 = j-t;
+    float Z0 = k-t;
+    float x0 = x-X0; /* The x,y,z distances from the cell origin */
+    float y0 = y-Y0;
+    float z0 = z-Z0;
+
+    float x1, y1, z1, x2, y2, z2, x3, y3, z3;
+    int ii, jj, kk;
+    float t0, t1, t2, t3;
+
+    /* For the 3D case, the simplex shape is a slightly irregular tetrahedron. */
+    /* Determine which simplex we are in. */
+    int i1, j1, k1; /* Offsets for second corner of simplex in (i,j,k) coords */
+    int i2, j2, k2; /* Offsets for third corner of simplex in (i,j,k) coords */
+
+/* This code would benefit from a backport from the GLSL version! */
+    if(x0>=y0) {
+      if(y0>=z0)
+        { i1=1; j1=0; k1=0; i2=1; j2=1; k2=0; } /* X Y Z order */
+        else if(x0>=z0) { i1=1; j1=0; k1=0; i2=1; j2=0; k2=1; } /* X Z Y order */
+        else { i1=0; j1=0; k1=1; i2=1; j2=0; k2=1; } /* Z X Y order */
+      }
+    else { /* x0<y0 */
+      if(y0<z0) { i1=0; j1=0; k1=1; i2=0; j2=1; k2=1; } /* Z Y X order */
+      else if(x0<z0) { i1=0; j1=1; k1=0; i2=0; j2=1; k2=1; } /* Y Z X order */
+      else { i1=0; j1=1; k1=0; i2=1; j2=1; k2=0; } /* Y X Z order */
+    }
+
+    /* A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z), */
+    /* a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and */
+    /* a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where */
+    /* c = 1/6. */
+
+    x1 = x0 - i1 + G3; /* Offsets for second corner in (x,y,z) coords */
+    y1 = y0 - j1 + G3;
+    z1 = z0 - k1 + G3;
+    x2 = x0 - i2 + 2.0f*G3; /* Offsets for third corner in (x,y,z) coords */
+    y2 = y0 - j2 + 2.0f*G3;
+    z2 = z0 - k2 + 2.0f*G3;
+    x3 = x0 - 1.0f + 3.0f*G3; /* Offsets for last corner in (x,y,z) coords */
+    y3 = y0 - 1.0f + 3.0f*G3;
+    z3 = z0 - 1.0f + 3.0f*G3;
+
+    /* Wrap the integer indices at 256, to avoid indexing perm[] out of bounds */
+    ii = i % 256;
+    jj = j % 256;
+    kk = k % 256;
+
+    /* Calculate the contribution from the four corners */
+    t0 = 0.6f - x0*x0 - y0*y0 - z0*z0;
+    if(t0 < 0.0f) n0 = 0.0f;
+    else {
+      t0 *= t0;
+      n0 = t0 * t0 * grad3(perm[ii+perm[jj+perm[kk]]], x0, y0, z0);
+    }
+
+    t1 = 0.6f - x1*x1 - y1*y1 - z1*z1;
+    if(t1 < 0.0f) n1 = 0.0f;
+    else {
+      t1 *= t1;
+      n1 = t1 * t1 * grad3(perm[ii+i1+perm[jj+j1+perm[kk+k1]]], x1, y1, z1);
+    }
+
+    t2 = 0.6f - x2*x2 - y2*y2 - z2*z2;
+    if(t2 < 0.0f) n2 = 0.0f;
+    else {
+      t2 *= t2;
+      n2 = t2 * t2 * grad3(perm[ii+i2+perm[jj+j2+perm[kk+k2]]], x2, y2, z2);
+    }
+
+    t3 = 0.6f - x3*x3 - y3*y3 - z3*z3;
+    if(t3<0.0f) n3 = 0.0f;
+    else {
+      t3 *= t3;
+      n3 = t3 * t3 * grad3(perm[ii+1+perm[jj+1+perm[kk+1]]], x3, y3, z3);
+    }
+
+    /* Add contributions from each corner to get the final noise value. */
+    /* The result is scaled to stay just inside [-1,1] */
+    return 32.0f * (n0 + n1 + n2 + n3); /* TODO: The scale factor is preliminary! */
+}
+
+/* 4D simplex noise */
+GLfloat _slang_library_noise4 (GLfloat x, GLfloat y, GLfloat z, GLfloat w)
+{
+  /* The skewing and unskewing factors are hairy again for the 4D case */
+#define F4 0.309016994f /* F4 = (Math.sqrt(5.0)-1.0)/4.0 */
+#define G4 0.138196601f /* G4 = (5.0-Math.sqrt(5.0))/20.0 */
+
+    float n0, n1, n2, n3, n4; /* Noise contributions from the five corners */
+
+    /* Skew the (x,y,z,w) space to determine which cell of 24 simplices we're in */
+    float s = (x + y + z + w) * F4; /* Factor for 4D skewing */
+    float xs = x + s;
+    float ys = y + s;
+    float zs = z + s;
+    float ws = w + s;
+    int i = FASTFLOOR(xs);
+    int j = FASTFLOOR(ys);
+    int k = FASTFLOOR(zs);
+    int l = FASTFLOOR(ws);
+
+    float t = (i + j + k + l) * G4; /* Factor for 4D unskewing */
+    float X0 = i - t; /* Unskew the cell origin back to (x,y,z,w) space */
+    float Y0 = j - t;
+    float Z0 = k - t;
+    float W0 = l - t;
+
+    float x0 = x - X0;  /* The x,y,z,w distances from the cell origin */
+    float y0 = y - Y0;
+    float z0 = z - Z0;
+    float w0 = w - W0;
+
+    /* 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 x0, y0, z0 and w0. */
+    /* The method below is a good way of finding the ordering of x,y,z,w and */
+    /* then find the correct traversal order for the simplex we’re in. */
+    /* First, six pair-wise comparisons are performed between each possible pair */
+    /* of the four coordinates, and the results are used to add up binary bits */
+    /* for an integer index. */
+    int c1 = (x0 > y0) ? 32 : 0;
+    int c2 = (x0 > z0) ? 16 : 0;
+    int c3 = (y0 > z0) ? 8 : 0;
+    int c4 = (x0 > w0) ? 4 : 0;
+    int c5 = (y0 > w0) ? 2 : 0;
+    int c6 = (z0 > w0) ? 1 : 0;
+    int c = c1 + c2 + c3 + c4 + c5 + c6;
+
+    int i1, j1, k1, l1; /* The integer offsets for the second simplex corner */
+    int i2, j2, k2, l2; /* The integer offsets for the third simplex corner */
+    int i3, j3, k3, l3; /* The integer offsets for the fourth simplex corner */
+
+    float x1, y1, z1, w1, x2, y2, z2, w2, x3, y3, z3, w3, x4, y4, z4, w4;
+    int ii, jj, kk, ll;
+    float t0, t1, t2, t3, t4;
+
+    /* simplex[c] is a 4-vector with the numbers 0, 1, 2 and 3 in some order. */
+    /* Many values of c will never occur, since e.g. x>y>z>w makes x<z, y<w and x<w */
+    /* impossible. Only the 24 indices which have non-zero entries make any sense. */
+    /* We use a thresholding to set the coordinates in turn from the largest magnitude. */
+    /* The number 3 in the "simplex" array is at the position of the largest coordinate. */
+    i1 = simplex[c][0]>=3 ? 1 : 0;
+    j1 = simplex[c][1]>=3 ? 1 : 0;
+    k1 = simplex[c][2]>=3 ? 1 : 0;
+    l1 = simplex[c][3]>=3 ? 1 : 0;
+    /* The number 2 in the "simplex" array is at the second largest coordinate. */
+    i2 = simplex[c][0]>=2 ? 1 : 0;
+    j2 = simplex[c][1]>=2 ? 1 : 0;
+    k2 = simplex[c][2]>=2 ? 1 : 0;
+    l2 = simplex[c][3]>=2 ? 1 : 0;
+    /* The number 1 in the "simplex" array is at the second smallest coordinate. */
+    i3 = simplex[c][0]>=1 ? 1 : 0;
+    j3 = simplex[c][1]>=1 ? 1 : 0;
+    k3 = simplex[c][2]>=1 ? 1 : 0;
+    l3 = simplex[c][3]>=1 ? 1 : 0;
+    /* The fifth corner has all coordinate offsets = 1, so no need to look that up. */
+
+    x1 = x0 - i1 + G4; /* Offsets for second corner in (x,y,z,w) coords */
+    y1 = y0 - j1 + G4;
+    z1 = z0 - k1 + G4;
+    w1 = w0 - l1 + G4;
+    x2 = x0 - i2 + 2.0f*G4; /* Offsets for third corner in (x,y,z,w) coords */
+    y2 = y0 - j2 + 2.0f*G4;
+    z2 = z0 - k2 + 2.0f*G4;
+    w2 = w0 - l2 + 2.0f*G4;
+    x3 = x0 - i3 + 3.0f*G4; /* Offsets for fourth corner in (x,y,z,w) coords */
+    y3 = y0 - j3 + 3.0f*G4;
+    z3 = z0 - k3 + 3.0f*G4;
+    w3 = w0 - l3 + 3.0f*G4;
+    x4 = x0 - 1.0f + 4.0f*G4; /* Offsets for last corner in (x,y,z,w) coords */
+    y4 = y0 - 1.0f + 4.0f*G4;
+    z4 = z0 - 1.0f + 4.0f*G4;
+    w4 = w0 - 1.0f + 4.0f*G4;
+
+    /* Wrap the integer indices at 256, to avoid indexing perm[] out of bounds */
+    ii = i % 256;
+    jj = j % 256;
+    kk = k % 256;
+    ll = l % 256;
+
+    /* Calculate the contribution from the five corners */
+    t0 = 0.6f - x0*x0 - y0*y0 - z0*z0 - w0*w0;
+    if(t0 < 0.0f) n0 = 0.0f;
+    else {
+      t0 *= t0;
+      n0 = t0 * t0 * grad4(perm[ii+perm[jj+perm[kk+perm[ll]]]], x0, y0, z0, w0);
+    }
+
+   t1 = 0.6f - x1*x1 - y1*y1 - z1*z1 - w1*w1;
+    if(t1 < 0.0f) n1 = 0.0f;
+    else {
+      t1 *= t1;
+      n1 = t1 * t1 * grad4(perm[ii+i1+perm[jj+j1+perm[kk+k1+perm[ll+l1]]]], x1, y1, z1, w1);
+    }
+
+   t2 = 0.6f - x2*x2 - y2*y2 - z2*z2 - w2*w2;
+    if(t2 < 0.0f) n2 = 0.0f;
+    else {
+      t2 *= t2;
+      n2 = t2 * t2 * grad4(perm[ii+i2+perm[jj+j2+perm[kk+k2+perm[ll+l2]]]], x2, y2, z2, w2);
+    }
+
+   t3 = 0.6f - x3*x3 - y3*y3 - z3*z3 - w3*w3;
+    if(t3 < 0.0f) n3 = 0.0f;
+    else {
+      t3 *= t3;
+      n3 = t3 * t3 * grad4(perm[ii+i3+perm[jj+j3+perm[kk+k3+perm[ll+l3]]]], x3, y3, z3, w3);
+    }
+
+   t4 = 0.6f - x4*x4 - y4*y4 - z4*z4 - w4*w4;
+    if(t4 < 0.0f) n4 = 0.0f;
+    else {
+      t4 *= t4;
+      n4 = t4 * t4 * grad4(perm[ii+1+perm[jj+1+perm[kk+1+perm[ll+1]]]], x4, y4, z4, w4);
+    }
+
+    /* Sum up and scale the result to cover the range [-1,1] */
+    return 27.0f * (n0 + n1 + n2 + n3 + n4); /* TODO: The scale factor is preliminary! */
+}
+