src/material.cc
branchpyrit
changeset 79 062b1c4143f7
parent 44 3763b26244f0
equal deleted inserted replaced
78:9569e9f35374 79:062b1c4143f7
       
     1 /*
       
     2  * material.cc: material and texture classes
       
     3  *
       
     4  * This file is part of Pyrit Ray Tracer.
       
     5  *
       
     6  * Copyright 2006, 2008  Radek Brich
       
     7  *
       
     8  * Permission is hereby granted, free of charge, to any person obtaining a copy
       
     9  * of this software and associated documentation files (the "Software"), to deal
       
    10  * in the Software without restriction, including without limitation the rights
       
    11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
       
    12  * copies of the Software, and to permit persons to whom the Software is
       
    13  * furnished to do so, subject to the following conditions:
       
    14  *
       
    15  * The above copyright notice and this permission notice shall be included in
       
    16  * all copies or substantial portions of the Software.
       
    17  *
       
    18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
       
    19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
       
    20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
       
    21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
       
    22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
       
    23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
       
    24  * THE SOFTWARE.
       
    25  */
       
    26 
       
    27 #include <math.h>
       
    28 
       
    29 #include "material.h"
       
    30 
       
    31 /**
       
    32  * Perlin noise
       
    33  * Based on JAVA REFERENCE IMPLEMENTATION OF IMPROVED NOISE by KEN PERLIN (COPYRIGHT 2002)
       
    34  */
       
    35 
       
    36 Float fade(Float t)
       
    37 {
       
    38 	return t * t * t * (t * (t * 6 - 15) + 10);
       
    39 }
       
    40 
       
    41 Float lerp(Float t, Float a, Float b)
       
    42 {
       
    43 	return a + t * (b - a);
       
    44 }
       
    45 
       
    46 Float grad(unsigned char hash, Float x, Float y, Float z)
       
    47 {
       
    48 	unsigned char h = hash & 15;            // CONVERT LO 4 BITS OF HASH CODE
       
    49 	Float	u = h<8 ? x : y,                 // INTO 12 GRADIENT DIRECTIONS.
       
    50 			v = h<4 ? y : h==12||h==14 ? x : z;
       
    51 	return ((h&1) == 0 ? u : -u) + ((h&2) == 0 ? v : -v);
       
    52 }
       
    53 
       
    54 const unsigned char p[512] =
       
    55 {
       
    56 	151,160,137,91,90,15,
       
    57 	131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
       
    58 	190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
       
    59 	88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
       
    60 	77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
       
    61 	102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
       
    62 	135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
       
    63 	5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
       
    64 	223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
       
    65 	129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
       
    66 	251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
       
    67 	49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
       
    68 	138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180,
       
    69 
       
    70 	151,160,137,91,90,15,
       
    71 	131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
       
    72 	190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
       
    73 	88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
       
    74 	77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
       
    75 	102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
       
    76 	135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
       
    77 	5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
       
    78 	223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
       
    79 	129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
       
    80 	251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
       
    81 	49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
       
    82 	138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180
       
    83 };
       
    84 
       
    85 
       
    86 Float perlin(Float x, Float y, Float z)
       
    87 {
       
    88 	int	X = (int)floor(x) & 255,
       
    89 		Y = (int)floor(y) & 255,
       
    90 		Z = (int)floor(z) & 255;
       
    91 	x -= floor(x);
       
    92 	y -= floor(y);
       
    93 	z -= floor(z);
       
    94 	Float	u = fade(x),
       
    95 			v = fade(y),
       
    96 			w = fade(z);
       
    97 	int	A = p[X  ]+Y, AA = p[A]+Z, AB = p[A+1]+Z,
       
    98 		B = p[X+1]+Y, BA = p[B]+Z, BB = p[B+1]+Z;
       
    99 
       
   100 	return	lerp(w, lerp(v, lerp(u, grad(p[AA  ], x  , y  , z   ),
       
   101 									grad(p[BA  ], x-1, y  , z   )),
       
   102 							lerp(u, grad(p[AB  ], x  , y-1, z   ),
       
   103 									grad(p[BB  ], x-1, y-1, z   ))),
       
   104 					lerp(v, lerp(u, grad(p[AA+1], x  , y  , z-1 ),
       
   105 									grad(p[BA+1], x-1, y  , z-1 )),
       
   106 							lerp(u, grad(p[AB+1], x  , y-1, z-1 ),
       
   107 									grad(p[BB+1], x-1, y-1, z-1 ))));
       
   108 }