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Comparing ray/src/common/fvect.c (file contents):
Revision 2.6 by greg, Sat Feb 22 02:07:22 2003 UTC vs.
Revision 2.17 by greg, Thu Nov 22 06:07:17 2012 UTC

# Line 5 | Line 5 | static const char      RCSid[] = "$Id$";
5   *  fvect.c - routines for floating-point vector calculations
6   */
7  
8 < /* ====================================================================
9 < * The Radiance Software License, Version 1.0
10 < *
11 < * Copyright (c) 1990 - 2002 The Regents of the University of California,
12 < * through Lawrence Berkeley National Laboratory.   All rights reserved.
13 < *
14 < * Redistribution and use in source and binary forms, with or without
15 < * modification, are permitted provided that the following conditions
16 < * are met:
17 < *
18 < * 1. Redistributions of source code must retain the above copyright
19 < *         notice, this list of conditions and the following disclaimer.
20 < *
21 < * 2. Redistributions in binary form must reproduce the above copyright
22 < *       notice, this list of conditions and the following disclaimer in
23 < *       the documentation and/or other materials provided with the
24 < *       distribution.
25 < *
26 < * 3. The end-user documentation included with the redistribution,
27 < *           if any, must include the following acknowledgment:
28 < *             "This product includes Radiance software
29 < *                 (http://radsite.lbl.gov/)
30 < *                 developed by the Lawrence Berkeley National Laboratory
31 < *               (http://www.lbl.gov/)."
32 < *       Alternately, this acknowledgment may appear in the software itself,
33 < *       if and wherever such third-party acknowledgments normally appear.
34 < *
35 < * 4. The names "Radiance," "Lawrence Berkeley National Laboratory"
36 < *       and "The Regents of the University of California" must
37 < *       not be used to endorse or promote products derived from this
38 < *       software without prior written permission. For written
39 < *       permission, please contact [email protected].
40 < *
41 < * 5. Products derived from this software may not be called "Radiance",
42 < *       nor may "Radiance" appear in their name, without prior written
43 < *       permission of Lawrence Berkeley National Laboratory.
44 < *
45 < * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
46 < * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
47 < * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
48 < * DISCLAIMED.   IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR
49 < * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
50 < * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
51 < * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
52 < * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
53 < * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
54 < * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
55 < * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56 < * SUCH DAMAGE.
57 < * ====================================================================
58 < *
59 < * This software consists of voluntary contributions made by many
60 < * individuals on behalf of Lawrence Berkeley National Laboratory.   For more
61 < * information on Lawrence Berkeley National Laboratory, please see
62 < * <http://www.lbl.gov/>.
63 < */
8 > #include "copyright.h"
9  
10   #include  <math.h>
11   #include  "fvect.h"
12  
13  
14   double
15 < fdot(v1, v2)                    /* return the dot product of two vectors */
16 < register FVECT  v1, v2;
15 > fdot(                           /* return the dot product of two vectors */
16 > const FVECT v1,
17 > const FVECT v2
18 > )
19   {
20          return(DOT(v1,v2));
21   }
22  
23  
24   double
25 < dist2(p1, p2)                   /* return square of distance between points */
26 < register FVECT  p1, p2;
25 > dist2(                          /* return square of distance between points */
26 > const FVECT p1,
27 > const FVECT p2
28 > )
29   {
30          FVECT  delta;
31  
# Line 89 | Line 38 | register FVECT  p1, p2;
38  
39  
40   double
41 < dist2line(p, ep1, ep2)          /* return square of distance to line */
42 < FVECT  p;               /* the point */
43 < FVECT  ep1, ep2;        /* points on the line */
41 > dist2line(                      /* return square of distance to line */
42 > const FVECT p,          /* the point */
43 > const FVECT ep1,
44 > const FVECT ep2         /* points on the line */
45 > )
46   {
47 <        register double  d, d1, d2;
47 >        double  d, d1, d2;
48  
49          d = dist2(ep1, ep2);
50          d1 = dist2(ep1, p);
# Line 104 | Line 55 | FVECT  ep1, ep2;       /* points on the line */
55  
56  
57   double
58 < dist2lseg(p, ep1, ep2)          /* return square of distance to line segment */
59 < FVECT  p;               /* the point */
60 < FVECT  ep1, ep2;        /* the end points */
58 > dist2lseg(                      /* return square of distance to line segment */
59 > const FVECT p,          /* the point */
60 > const FVECT ep1,
61 > const FVECT ep2         /* the end points */
62 > )
63   {
64 <        register double  d, d1, d2;
64 >        double  d, d1, d2;
65  
66          d = dist2(ep1, ep2);
67          d1 = dist2(ep1, p);
# Line 128 | Line 81 | FVECT  ep1, ep2;       /* the end points */
81  
82  
83   void
84 < fcross(vres, v1, v2)            /* vres = v1 X v2 */
85 < register FVECT  vres, v1, v2;
84 > fcross(                         /* vres = v1 X v2 */
85 > FVECT vres,
86 > const FVECT v1,
87 > const FVECT v2
88 > )
89   {
90          vres[0] = v1[1]*v2[2] - v1[2]*v2[1];
91          vres[1] = v1[2]*v2[0] - v1[0]*v2[2];
# Line 138 | Line 94 | register FVECT  vres, v1, v2;
94  
95  
96   void
97 < fvsum(vres, v0, v1, f)          /* vres = v0 + f*v1 */
98 < register FVECT  vres, v0, v1;
99 < register double  f;
97 > fvsum(                          /* vres = v0 + f*v1 */
98 > FVECT vres,
99 > const FVECT v0,
100 > const FVECT v1,
101 > double f
102 > )
103   {
104          vres[0] = v0[0] + f*v1[0];
105          vres[1] = v0[1] + f*v1[1];
# Line 149 | Line 108 | register double  f;
108  
109  
110   double
111 < normalize(v)                    /* normalize a vector, return old magnitude */
112 < register FVECT  v;
111 > normalize(                      /* normalize a vector, return old magnitude */
112 > FVECT  v
113 > )
114   {
115 <        register double  len, d;
115 >        double  len, d;
116          
117          d = DOT(v, v);
118          
119 <        if (d <= 0.0)
119 >        if (d == 0.0)
120                  return(0.0);
121          
122 <        if (d <= 1.0+FTINY && d >= 1.0-FTINY)
122 >        if ((d <= 1.0+FTINY) & (d >= 1.0-FTINY)) {
123                  len = 0.5 + 0.5*d;      /* first order approximation */
124 <        else
124 >                d = 2.0 - len;
125 >        } else {
126                  len = sqrt(d);
127 <
128 <        v[0] *= d = 1.0/len;
127 >                d = 1.0/len;
128 >        }
129 >        v[0] *= d;
130          v[1] *= d;
131          v[2] *= d;
132  
# Line 172 | Line 134 | register FVECT  v;
134   }
135  
136  
137 + int
138 + closestapproach(                        /* closest approach of two rays */
139 + RREAL t[2],             /* returned distances along each ray */
140 + const FVECT rorg0,              /* first origin */
141 + const FVECT rdir0,              /* first direction (normalized) */
142 + const FVECT rorg1,              /* second origin */
143 + const FVECT rdir1               /* second direction (normalized) */
144 + )
145 + {
146 +        double  dotprod = DOT(rdir0, rdir1);
147 +        double  denom = 1. - dotprod*dotprod;
148 +        double  o1o2_d1;
149 +        FVECT   o0o1;
150 +
151 +        if (denom <= FTINY) {           /* check if lines are parallel */
152 +                t[0] = t[1] = 0.0;
153 +                return(0);
154 +        }
155 +        VSUB(o0o1, rorg0, rorg1);
156 +        o1o2_d1 = DOT(o0o1, rdir1);
157 +        t[0] = (o1o2_d1*dotprod - DOT(o0o1,rdir0)) / denom;
158 +        t[1] = o1o2_d1 + t[0]*dotprod;
159 +        return(1);
160 + }
161 +
162 +
163   void
164 < spinvector(vres, vorig, vnorm, theta)   /* rotate vector around normal */
165 < FVECT  vres, vorig, vnorm;
166 < double  theta;
164 > spinvector(                             /* rotate vector around normal */
165 > FVECT vres,             /* returned vector (same magnitude as vorig) */
166 > const FVECT vorig,              /* original vector */
167 > const FVECT vnorm,              /* normalized vector for rotation */
168 > double theta            /* right-hand radians */
169 > )
170   {
171          double  sint, cost, normprod;
172          FVECT  vperp;
173 <        register int  i;
173 >        int  i;
174          
175          if (theta == 0.0) {
176                  if (vres != vorig)
# Line 192 | Line 183 | double  theta;
183          fcross(vperp, vnorm, vorig);
184          for (i = 0; i < 3; i++)
185                  vres[i] = vorig[i]*cost + vnorm[i]*normprod + vperp[i]*sint;
186 + }
187 +
188 + double
189 + geodesic(               /* rotate vector on great circle towards target */
190 + FVECT vres,             /* returned vector (same magnitude as vorig) */
191 + const FVECT vorig,      /* original vector */
192 + const FVECT vtarg,      /* vector we are rotating towards */
193 + double t,               /* amount along arc directed towards vtarg */
194 + int meas                /* distance measure (radians, absolute, relative) */
195 + )
196 + {
197 +        FVECT   normtarg;
198 +        double  volen, dotprod, sintr, cost;
199 +        int     i;
200 +
201 +        VCOPY(normtarg, vtarg);         /* in case vtarg==vres */
202 +        if (vres != vorig)
203 +                VCOPY(vres, vorig);
204 +        if (t == 0.0)
205 +                return(VLEN(vres));     /* no rotation requested */
206 +        if ((volen = normalize(vres)) == 0.0)
207 +                return(0.0);
208 +        if (normalize(normtarg) == 0.0)
209 +                return(0.0);            /* target vector is zero */
210 +        dotprod = DOT(vres, normtarg);
211 +                                        /* check for colinear */
212 +        if (dotprod >= 1.0-FTINY*FTINY) {
213 +                if (meas != GEOD_REL)
214 +                        return(0.0);
215 +                vres[0] *= volen; vres[1] *= volen; vres[2] *= volen;
216 +                return(volen);
217 +        }
218 +        if (dotprod <= -1.0+FTINY*FTINY)
219 +                return(0.0);
220 +        if (meas == GEOD_ABS)
221 +                t /= volen;
222 +        else if (meas == GEOD_REL)
223 +                t *= acos(dotprod);
224 +        cost = cos(t);
225 +        sintr = sin(t) / sqrt(1. - dotprod*dotprod);
226 +        for (i = 0; i < 3; i++)
227 +                vres[i] = volen*( cost*vres[i] +
228 +                                  sintr*(normtarg[i] - dotprod*vres[i]) );
229 +
230 +        return(volen);                  /* return vector length */
231   }

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