src/rt/noise3.c

#ifndef lint
static const char       RCSid[] = "$Id$";
#endif
/*
 *  noise3.c - noise functions for random textures.
 *
 *     Credit for the smooth algorithm goes to Ken Perlin.
 *     (ref. SIGGRAPH Vol 19, No 3, pp 287-96)
 */

/* ====================================================================
 * The Radiance Software License, Version 1.0
 *
 * Copyright (c) 1990 - 2002 The Regents of the University of California,
 * through Lawrence Berkeley National Laboratory.   All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *         notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *           if any, must include the following acknowledgment:
 *             "This product includes Radiance software
 *                 (http://radsite.lbl.gov/)
 *                 developed by the Lawrence Berkeley National Laboratory
 *               (http://www.lbl.gov/)."
 *       Alternately, this acknowledgment may appear in the software itself,
 *       if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Radiance," "Lawrence Berkeley National Laboratory"
 *       and "The Regents of the University of California" must
 *       not be used to endorse or promote products derived from this
 *       software without prior written permission. For written
 *       permission, please contact [email protected].
 *
 * 5. Products derived from this software may not be called "Radiance",
 *       nor may "Radiance" appear in their name, without prior written
 *       permission of Lawrence Berkeley National Laboratory.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.   IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of Lawrence Berkeley National Laboratory.   For more
 * information on Lawrence Berkeley National Laboratory, please see
 * <http://www.lbl.gov/>.
 */

#include  <math.h>

#define  A              0
#define  B              1
#define  C              2
#define  D              3

#define  rand3a(x,y,z)  frand(67*(x)+59*(y)+71*(z))
#define  rand3b(x,y,z)  frand(73*(x)+79*(y)+83*(z))
#define  rand3c(x,y,z)  frand(89*(x)+97*(y)+101*(z))
#define  rand3d(x,y,z)  frand(103*(x)+107*(y)+109*(z))

#define  hpoly1(t)      ((2.0*t-3.0)*t*t+1.0)
#define  hpoly2(t)      (-2.0*t+3.0)*t*t
#define  hpoly3(t)      ((t-2.0)*t+1.0)*t
#define  hpoly4(t)      (t-1.0)*t*t

#define  hermite(p0,p1,r0,r1,t)  (      p0*hpoly1(t) + \
                                        p1*hpoly2(t) + \
                                        r0*hpoly3(t) + \
                                        r1*hpoly4(t) )

static char  noise_name[4][8] = {"noise3x", "noise3y", "noise3z", "noise3"};
static char  fnoise_name[] = "fnoise3";
static char  hermite_name[] = "hermite";

double  *noise3(), fnoise3(), argument(), frand();
static  interpolate();

static long  xlim[3][2];
static double  xarg[3];

#define  EPSILON        .001            /* error allowed in fractal */

#define  frand3(x,y,z)  frand(17*(x)+23*(y)+29*(z))


static double
l_noise3(nam)                   /* compute a noise function */
register char  *nam;
{
        register int  i;
        double  x[3];
                                        /* get point */
        x[0] = argument(1);
        x[1] = argument(2);
        x[2] = argument(3);
                                        /* make appropriate call */
        if (nam == fnoise_name)
                return(fnoise3(x));
        i = 4;
        while (i--)
                if (nam == noise_name[i])
                        return(noise3(x)[i]);
        eputs(nam);
        eputs(": called l_noise3!\n");
        quit(1);
}


double
l_hermite()                     /* library call for hermite interpolation */
{
        double  t;
        
        t = argument(5);
        return( hermite(argument(1), argument(2),
                        argument(3), argument(4), t) );
}


setnoisefuncs()                 /* add noise functions to library */
{
        register int  i;

        funset(hermite_name, 5, ':', l_hermite);
        funset(fnoise_name, 3, ':', l_noise3);
        i = 4;
        while (i--)
                funset(noise_name[i], 3, ':', l_noise3);
}


double *
noise3(xnew)                    /* compute the noise function */
register double  xnew[3];
{
        static double  x[3] = {-100000.0, -100000.0, -100000.0};
        static double  f[4];

        if (x[0]==xnew[0] && x[1]==xnew[1] && x[2]==xnew[2])
                return(f);
        x[0] = xnew[0]; x[1] = xnew[1]; x[2] = xnew[2];
        xlim[0][0] = floor(x[0]); xlim[0][1] = xlim[0][0] + 1;
        xlim[1][0] = floor(x[1]); xlim[1][1] = xlim[1][0] + 1;
        xlim[2][0] = floor(x[2]); xlim[2][1] = xlim[2][0] + 1;
        xarg[0] = x[0] - xlim[0][0];
        xarg[1] = x[1] - xlim[1][0];
        xarg[2] = x[2] - xlim[2][0];
        interpolate(f, 0, 3);
        return(f);
}


static
interpolate(f, i, n)
double  f[4];
register int  i, n;
{
        double  f0[4], f1[4], hp1, hp2;

        if (n == 0) {
                f[A] = rand3a(xlim[0][i&1],xlim[1][i>>1&1],xlim[2][i>>2]);
                f[B] = rand3b(xlim[0][i&1],xlim[1][i>>1&1],xlim[2][i>>2]);
                f[C] = rand3c(xlim[0][i&1],xlim[1][i>>1&1],xlim[2][i>>2]);
                f[D] = rand3d(xlim[0][i&1],xlim[1][i>>1&1],xlim[2][i>>2]);
        } else {
                n--;
                interpolate(f0, i, n);
                interpolate(f1, i | 1<<n, n);
                hp1 = hpoly1(xarg[n]); hp2 = hpoly2(xarg[n]);
                f[A] = f0[A]*hp1 + f1[A]*hp2;
                f[B] = f0[B]*hp1 + f1[B]*hp2;
                f[C] = f0[C]*hp1 + f1[C]*hp2;
                f[D] = f0[D]*hp1 + f1[D]*hp2 +
                                f0[n]*hpoly3(xarg[n]) + f1[n]*hpoly4(xarg[n]);
        }
}


double
frand(s)                        /* get random number from seed */
register long  s;
{
        s = s<<13 ^ s;
        return(1.0-((s*(s*s*15731+789221)+1376312589)&0x7fffffff)/1073741824.0);
}


double
fnoise3(p)                      /* compute fractal noise function */
double  p[3];
{
        long  t[3], v[3], beg[3];
        double  fval[8], fc;
        int  branch;
        register long  s;
        register int  i, j;
                                                /* get starting cube */
        s = (long)(1.0/EPSILON);
        for (i = 0; i < 3; i++) {
                t[i] = s*p[i];
                beg[i] = s*floor(p[i]);
        }
        for (j = 0; j < 8; j++) {
                for (i = 0; i < 3; i++) {
                        v[i] = beg[i];
                        if (j & 1<<i)
                                v[i] += s;
                }
                fval[j] = frand3(v[0],v[1],v[2]);
        }
                                                /* compute fractal */
        for ( ; ; ) {
                fc = 0.0;
                for (j = 0; j < 8; j++)
                        fc += fval[j];
                fc *= 0.125;
                if ((s >>= 1) == 0)
                        return(fc);             /* close enough */
                branch = 0;
                for (i = 0; i < 3; i++) {       /* do center */
                        v[i] = beg[i] + s;
                        if (t[i] > v[i]) {
                                branch |= 1<<i;
                        }
                }
                fc += s*EPSILON*frand3(v[0],v[1],v[2]);
                fval[~branch & 7] = fc;
                for (i = 0; i < 3; i++) {       /* do faces */
                        if (branch & 1<<i)
                                v[i] += s;
                        else
                                v[i] -= s;
                        fc = 0.0;
                        for (j = 0; j < 8; j++)
                                if (~(j^branch) & 1<<i)
                                        fc += fval[j];
                        fc = 0.25*fc + s*EPSILON*frand3(v[0],v[1],v[2]);
                        fval[~(branch^1<<i) & 7] = fc;
                        v[i] = beg[i] + s;
                }
                for (i = 0; i < 3; i++) {       /* do edges */
                        j = (i+1)%3;
                        if (branch & 1<<j)
                                v[j] += s;
                        else
                                v[j] -= s;
                        j = (i+2)%3;
                        if (branch & 1<<j)
                                v[j] += s;
                        else
                                v[j] -= s;
                        fc = fval[branch & ~(1<<i)];
                        fc += fval[branch | 1<<i];
                        fc = 0.5*fc + s*EPSILON*frand3(v[0],v[1],v[2]);
                        fval[branch^1<<i] = fc;
                        j = (i+1)%3;
                        v[j] = beg[j] + s;
                        j = (i+2)%3;
                        v[j] = beg[j] + s;
                }
                for (i = 0; i < 3; i++)         /* new cube */
                        if (branch & 1<<i)
                                beg[i] += s;
        }
}
Revision:	2.6
Committed:	Sat Feb 22 02:07:29 2003 UTC (21 years, 2 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.5:	+57 -6 lines
Log Message:	Changes and check-in for 3.5 release Includes new source files and modifications not recorded for many years See ray/doc/notes/ReleaseNotes for notes between 3.1 and 3.5 release
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.6	static const char RCSid[] = "$Id$";
3	greg	1.1	#endif
4			/*
5			* noise3.c - noise functions for random textures.
6			*
7			* Credit for the smooth algorithm goes to Ken Perlin.
8			* (ref. SIGGRAPH Vol 19, No 3, pp 287-96)
9	greg	2.6	*/
10
11			/* ====================================================================
12			* The Radiance Software License, Version 1.0
13			*
14			* Copyright (c) 1990 - 2002 The Regents of the University of California,
15			* through Lawrence Berkeley National Laboratory. All rights reserved.
16			*
17			* Redistribution and use in source and binary forms, with or without
18			* modification, are permitted provided that the following conditions
19			* are met:
20			*
21			* 1. Redistributions of source code must retain the above copyright
22			* notice, this list of conditions and the following disclaimer.
23			*
24			* 2. Redistributions in binary form must reproduce the above copyright
25			* notice, this list of conditions and the following disclaimer in
26			* the documentation and/or other materials provided with the
27			* distribution.
28			*
29			* 3. The end-user documentation included with the redistribution,
30			* if any, must include the following acknowledgment:
31			* "This product includes Radiance software
32			* (http://radsite.lbl.gov/)
33			* developed by the Lawrence Berkeley National Laboratory
34			* (http://www.lbl.gov/)."
35			* Alternately, this acknowledgment may appear in the software itself,
36			* if and wherever such third-party acknowledgments normally appear.
37			*
38			* 4. The names "Radiance," "Lawrence Berkeley National Laboratory"
39			* and "The Regents of the University of California" must
40			* not be used to endorse or promote products derived from this
41			* software without prior written permission. For written
42			* permission, please contact [email protected].
43			*
44			* 5. Products derived from this software may not be called "Radiance",
45			* nor may "Radiance" appear in their name, without prior written
46			* permission of Lawrence Berkeley National Laboratory.
47			*
48			* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
49			* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
50			* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
51			* DISCLAIMED. IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR
52			* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
53			* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
54			* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
55			* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
56			* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
57			* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
58			* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59			* SUCH DAMAGE.
60			* ====================================================================
61	greg	1.1	*
62	greg	2.6	* This software consists of voluntary contributions made by many
63			* individuals on behalf of Lawrence Berkeley National Laboratory. For more
64			* information on Lawrence Berkeley National Laboratory, please see
65			* <http://www.lbl.gov/>.
66	greg	1.1	*/
67
68	greg	2.2	#include <math.h>
69	greg	1.1
70			#define A 0
71			#define B 1
72			#define C 2
73			#define D 3
74
75			#define rand3a(x,y,z) frand(67(x)+59(y)+71*(z))
76			#define rand3b(x,y,z) frand(73(x)+79(y)+83*(z))
77			#define rand3c(x,y,z) frand(89(x)+97(y)+101*(z))
78			#define rand3d(x,y,z) frand(103(x)+107(y)+109*(z))
79
80	greg	1.7	#define hpoly1(t) ((2.0t-3.0)t*t+1.0)
81			#define hpoly2(t) (-2.0t+3.0)t*t
82			#define hpoly3(t) ((t-2.0)t+1.0)t
83			#define hpoly4(t) (t-1.0)tt
84	greg	1.1
85	greg	1.7	#define hermite(p0,p1,r0,r1,t) ( p0*hpoly1(t) + \
86			p1*hpoly2(t) + \
87			r0*hpoly3(t) + \
88			r1*hpoly4(t) )
89
90	greg	2.5	static char noise_name[4][8] = {"noise3x", "noise3y", "noise3z", "noise3"};
91	greg	1.5	static char fnoise_name[] = "fnoise3";
92			static char hermite_name[] = "hermite";
93	greg	1.1
94	greg	1.5	double *noise3(), fnoise3(), argument(), frand();
95	greg	2.3	static interpolate();
96	greg	1.5
97	greg	1.1	static long xlim[3][2];
98			static double xarg[3];
99
100	greg	2.4	#define EPSILON .001 /* error allowed in fractal */
101	greg	1.1
102	greg	1.3	#define frand3(x,y,z) frand(17(x)+23(y)+29*(z))
103	greg	1.1
104
105	greg	1.5	static double
106			l_noise3(nam) /* compute a noise function */
107			register char *nam;
108	greg	1.1	{
109	greg	1.5	register int i;
110			double x[3];
111			/* get point */
112			x[0] = argument(1);
113			x[1] = argument(2);
114			x[2] = argument(3);
115			/* make appropriate call */
116			if (nam == fnoise_name)
117			return(fnoise3(x));
118			i = 4;
119			while (i--)
120			if (nam == noise_name[i])
121			return(noise3(x)[i]);
122	greg	1.6	eputs(nam);
123			eputs(": called l_noise3!\n");
124	greg	1.5	quit(1);
125	greg	1.1	}
126
127
128			double
129	greg	1.5	l_hermite() /* library call for hermite interpolation */
130	greg	1.1	{
131	greg	1.5	double t;
132
133			t = argument(5);
134			return( hermite(argument(1), argument(2),
135			argument(3), argument(4), t) );
136	greg	1.1	}
137
138
139	greg	1.5	setnoisefuncs() /* add noise functions to library */
140	greg	1.1	{
141	greg	1.5	register int i;
142	greg	1.1
143	greg	1.5	funset(hermite_name, 5, ':', l_hermite);
144			funset(fnoise_name, 3, ':', l_noise3);
145			i = 4;
146			while (i--)
147			funset(noise_name[i], 3, ':', l_noise3);
148	greg	1.1	}
149
150
151			double *
152			noise3(xnew) /* compute the noise function */
153			register double xnew[3];
154			{
155			static double x[3] = {-100000.0, -100000.0, -100000.0};
156			static double f[4];
157
158			if (x[0]==xnew[0] && x[1]==xnew[1] && x[2]==xnew[2])
159			return(f);
160			x[0] = xnew[0]; x[1] = xnew[1]; x[2] = xnew[2];
161			xlim[0][0] = floor(x[0]); xlim[0][1] = xlim[0][0] + 1;
162			xlim[1][0] = floor(x[1]); xlim[1][1] = xlim[1][0] + 1;
163			xlim[2][0] = floor(x[2]); xlim[2][1] = xlim[2][0] + 1;
164			xarg[0] = x[0] - xlim[0][0];
165			xarg[1] = x[1] - xlim[1][0];
166			xarg[2] = x[2] - xlim[2][0];
167			interpolate(f, 0, 3);
168			return(f);
169			}
170
171
172			static
173			interpolate(f, i, n)
174			double f[4];
175			register int i, n;
176			{
177	greg	1.7	double f0[4], f1[4], hp1, hp2;
178	greg	1.1
179			if (n == 0) {
180			f[A] = rand3a(xlim[0][i&1],xlim[1][i>>1&1],xlim[2][i>>2]);
181			f[B] = rand3b(xlim[0][i&1],xlim[1][i>>1&1],xlim[2][i>>2]);
182			f[C] = rand3c(xlim[0][i&1],xlim[1][i>>1&1],xlim[2][i>>2]);
183			f[D] = rand3d(xlim[0][i&1],xlim[1][i>>1&1],xlim[2][i>>2]);
184			} else {
185			n--;
186			interpolate(f0, i, n);
187			interpolate(f1, i \| 1<<n, n);
188	greg	1.7	hp1 = hpoly1(xarg[n]); hp2 = hpoly2(xarg[n]);
189			f[A] = f0[A]hp1 + f1[A]hp2;
190			f[B] = f0[B]hp1 + f1[B]hp2;
191			f[C] = f0[C]hp1 + f1[C]hp2;
192			f[D] = f0[D]hp1 + f1[D]hp2 +
193			f0[n]hpoly3(xarg[n]) + f1[n]hpoly4(xarg[n]);
194	greg	1.1	}
195			}
196
197
198			double
199			frand(s) /* get random number from seed */
200			register long s;
201			{
202			s = s<<13 ^ s;
203			return(1.0-((s(ss*15731+789221)+1376312589)&0x7fffffff)/1073741824.0);
204			}
205
206
207			double
208			fnoise3(p) /* compute fractal noise function */
209	greg	1.3	double p[3];
210	greg	1.1	{
211	greg	1.4	long t[3], v[3], beg[3];
212	greg	1.3	double fval[8], fc;
213			int branch;
214	greg	1.4	register long s;
215	greg	1.1	register int i, j;
216			/* get starting cube */
217	greg	1.3	s = (long)(1.0/EPSILON);
218			for (i = 0; i < 3; i++) {
219			t[i] = s*p[i];
220			beg[i] = s*floor(p[i]);
221			}
222	greg	1.1	for (j = 0; j < 8; j++) {
223			for (i = 0; i < 3; i++) {
224			v[i] = beg[i];
225			if (j & 1<<i)
226	greg	1.3	v[i] += s;
227	greg	1.1	}
228			fval[j] = frand3(v[0],v[1],v[2]);
229			}
230			/* compute fractal */
231			for ( ; ; ) {
232	greg	1.4	fc = 0.0;
233			for (j = 0; j < 8; j++)
234			fc += fval[j];
235			fc *= 0.125;
236			if ((s >>= 1) == 0)
237			return(fc); /* close enough */
238	greg	1.1	branch = 0;
239			for (i = 0; i < 3; i++) { /* do center */
240			v[i] = beg[i] + s;
241	greg	1.3	if (t[i] > v[i]) {
242	greg	1.1	branch \|= 1<<i;
243	greg	1.3	}
244	greg	1.1	}
245	greg	1.3	fc += sEPSILONfrand3(v[0],v[1],v[2]);
246	greg	1.1	fval[~branch & 7] = fc;
247			for (i = 0; i < 3; i++) { /* do faces */
248			if (branch & 1<<i)
249			v[i] += s;
250			else
251			v[i] -= s;
252			fc = 0.0;
253			for (j = 0; j < 8; j++)
254			if (~(j^branch) & 1<<i)
255			fc += fval[j];
256	greg	1.3	fc = 0.25fc + sEPSILON*frand3(v[0],v[1],v[2]);
257	greg	1.1	fval[~(branch^1<<i) & 7] = fc;
258			v[i] = beg[i] + s;
259			}
260			for (i = 0; i < 3; i++) { /* do edges */
261			j = (i+1)%3;
262			if (branch & 1<<j)
263			v[j] += s;
264			else
265			v[j] -= s;
266			j = (i+2)%3;
267			if (branch & 1<<j)
268			v[j] += s;
269			else
270			v[j] -= s;
271			fc = fval[branch & ~(1<<i)];
272			fc += fval[branch \| 1<<i];
273	greg	1.3	fc = 0.5fc + sEPSILON*frand3(v[0],v[1],v[2]);
274	greg	1.1	fval[branch^1<<i] = fc;
275			j = (i+1)%3;
276			v[j] = beg[j] + s;
277			j = (i+2)%3;
278			v[j] = beg[j] + s;
279			}
280			for (i = 0; i < 3; i++) /* new cube */
281			if (branch & 1<<i)
282			beg[i] += s;
283			}
284			}