--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/noise.cc Thu Oct 25 16:40:22 2007 +0200
@@ -0,0 +1,134 @@
+/*
+Based on
+JAVA REFERENCE IMPLEMENTATION OF IMPROVED NOISE
+by KEN PERLIN (COPYRIGHT 2002)
+*/
+
+#include <math.h>
+
+#include "noise.h"
+
+double fade(double t)
+{
+ return t * t * t * (t * (t * 6 - 15) + 10);
+}
+
+double lerp(double t, double a, double b)
+{
+ return a + t * (b - a);
+}
+
+double grad(unsigned char hash, double x, double y, double z)
+{
+ unsigned char h = hash & 15; // CONVERT LO 4 BITS OF HASH CODE
+ double u = h<8 ? x : y, // INTO 12 GRADIENT DIRECTIONS.
+ v = h<4 ? y : h==12||h==14 ? x : z;
+ return ((h&1) == 0 ? u : -u) + ((h&2) == 0 ? v : -v);
+}
+
+unsigned char p[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
+ };
+
+
+double perlin(double x, double y, double z)
+{
+ int X = (int)floor(x) & 255, // FIND UNIT CUBE THAT
+ Y = (int)floor(y) & 255, // CONTAINS POINT.
+ Z = (int)floor(z) & 255;
+ x -= floor(x); // FIND RELATIVE X,Y,Z
+ y -= floor(y); // OF POINT IN CUBE.
+ z -= floor(z);
+ double u = fade(x), // COMPUTE FADE CURVES
+ v = fade(y), // FOR EACH OF X,Y,Z.
+ w = fade(z);
+ int A = p[X ]+Y, AA = p[A]+Z, AB = p[A+1]+Z, // HASH COORDINATES OF
+ B = p[X+1]+Y, BA = p[B]+Z, BB = p[B+1]+Z; // THE 8 CUBE CORNERS,
+
+ return lerp(w, lerp(v, lerp(u, grad(p[AA ], x , y , z ), // AND ADD
+ grad(p[BA ], x-1, y , z )), // BLENDED
+ lerp(u, grad(p[AB ], x , y-1, z ), // RESULTS
+ grad(p[BB ], x-1, y-1, z ))),// FROM 8
+ lerp(v, lerp(u, grad(p[AA+1], x , y , z-1 ), // CORNERS
+ grad(p[BA+1], x-1, y , z-1 )), // OF CUBE
+ lerp(u, grad(p[AB+1], x , y-1, z-1 ),
+ grad(p[BB+1], x-1, y-1, z-1 ))));
+}
+
+
+/*
+// JAVA REFERENCE IMPLEMENTATION OF IMPROVED NOISE - COPYRIGHT 2002 KEN PERLIN.
+
+public final class ImprovedNoise {
+ static public double noise(double x, double y, double z) {
+ int X = (int)Math.floor(x) & 255, // FIND UNIT CUBE THAT
+ Y = (int)Math.floor(y) & 255, // CONTAINS POINT.
+ Z = (int)Math.floor(z) & 255;
+ x -= Math.floor(x); // FIND RELATIVE X,Y,Z
+ y -= Math.floor(y); // OF POINT IN CUBE.
+ z -= Math.floor(z);
+ double u = fade(x), // COMPUTE FADE CURVES
+ v = fade(y), // FOR EACH OF X,Y,Z.
+ w = fade(z);
+ int A = p[X ]+Y, AA = p[A]+Z, AB = p[A+1]+Z, // HASH COORDINATES OF
+ B = p[X+1]+Y, BA = p[B]+Z, BB = p[B+1]+Z; // THE 8 CUBE CORNERS,
+
+ return lerp(w, lerp(v, lerp(u, grad(p[AA ], x , y , z ), // AND ADD
+ grad(p[BA ], x-1, y , z )), // BLENDED
+ lerp(u, grad(p[AB ], x , y-1, z ), // RESULTS
+ grad(p[BB ], x-1, y-1, z ))),// FROM 8
+ lerp(v, lerp(u, grad(p[AA+1], x , y , z-1 ), // CORNERS
+ grad(p[BA+1], x-1, y , z-1 )), // OF CUBE
+ lerp(u, grad(p[AB+1], x , y-1, z-1 ),
+ grad(p[BB+1], x-1, y-1, z-1 ))));
+ }
+ static double fade(double t) { return t * t * t * (t * (t * 6 - 15) + 10); }
+ static double lerp(double t, double a, double b) { return a + t * (b - a); }
+ static double grad(int hash, double x, double y, double z) {
+ int h = hash & 15; // CONVERT LO 4 BITS OF HASH CODE
+ double u = h<8 ? x : y, // INTO 12 GRADIENT DIRECTIONS.
+ v = h<4 ? y : h==12||h==14 ? x : z;
+ return ((h&1) == 0 ? u : -u) + ((h&2) == 0 ? v : -v);
+ }
+ static final int p[] = new int[512], permutation[] = { 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
+ };
+ static { for (int i=0; i < 256 ; i++) p[256+i] = p[i] = permutation[i]; }
+}
+*/