From f9ebf19ba3ca4c3ee67cc88bbea407d4dd734249 Mon Sep 17 00:00:00 2001 From: xleroy Date: Wed, 17 Feb 2010 13:25:03 +0000 Subject: 3 more benchmarks git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@1252 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e --- test/c/perlin.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 test/c/perlin.c (limited to 'test/c/perlin.c') diff --git a/test/c/perlin.c b/test/c/perlin.c new file mode 100644 index 00000000..1559c1c9 --- /dev/null +++ b/test/c/perlin.c @@ -0,0 +1,75 @@ +// perlin noise, derived from the Java reference implementation at +// http://mrl.nyu.edu/~perlin/noise/ + +#include +#include + +static int p[512]; + +static int permutation[256] = { 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 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 double noise(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 )))); +} + +static void init() { + int i = 0; + for (i=0; i < 256 ; i++) + p[256+i] = p[i] = permutation[i]; +} + +int main() { + init(); + + double x, y, z, sum = 0.0; + for (x = -11352.57; x < 23561.57; x += .1235) + for (y = -346.1235; y < 124.124; y += 1.4325) + for (z = -156.235; y < 23.2345; y += 2.45) + sum += noise(x, y, z); + + printf("%.4e\n", sum); + return 0; +} -- cgit