1 |
greg |
1.1 |
/* Copyright (c) 1991 Regents of the University of California */ |
2 |
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3 |
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#ifndef lint |
4 |
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static char SCCSid[] = "$SunId$ LBL"; |
5 |
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#endif |
6 |
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7 |
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/* |
8 |
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* Compute pixels for glare calculation |
9 |
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*/ |
10 |
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11 |
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#include "glare.h" |
12 |
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#include <sys/param.h> |
13 |
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/* compute rtrace buffer size */ |
14 |
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#ifndef PIPE_BUF |
15 |
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#define PIPE_BUF 512 /* hyperconservative */ |
16 |
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#endif |
17 |
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#define MAXPIX (PIPE_BUF/(6*sizeof(float)) - 1) |
18 |
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19 |
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#ifndef BSD |
20 |
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#define vfork fork |
21 |
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#endif |
22 |
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23 |
greg |
1.11 |
#define MAXSBUF 524268 /* maximum total size of scanline buffer */ |
24 |
greg |
1.9 |
#define HSIZE 317 /* size of scanline hash table */ |
25 |
greg |
1.8 |
#define NRETIRE 16 /* number of scanlines to retire at once */ |
26 |
greg |
1.1 |
|
27 |
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int rt_pid = -1; /* process id for rtrace */ |
28 |
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int fd_tort, fd_fromrt; /* pipe descriptors */ |
29 |
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30 |
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FILE *pictfp = NULL; /* picture file pointer */ |
31 |
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double exposure; /* picture exposure */ |
32 |
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int pxsiz, pysiz; /* picture dimensions */ |
33 |
greg |
1.8 |
|
34 |
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static int curpos; /* current scanline */ |
35 |
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static long *scanpos; /* scanline positions */ |
36 |
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37 |
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typedef struct scan { |
38 |
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int y; /* scanline position */ |
39 |
greg |
1.1 |
long lused; /* for LRU replacement */ |
40 |
greg |
1.8 |
struct scan *next; /* next in this hash or free list */ |
41 |
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/* followed by the scanline data */ |
42 |
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} SCAN; /* buffered scanline */ |
43 |
greg |
1.1 |
|
44 |
greg |
1.8 |
#define scandata(sl) ((COLR *)((sl)+1)) |
45 |
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#define shash(y) ((y)%HSIZE) |
46 |
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47 |
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static SCAN *freelist; /* scanline free list */ |
48 |
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static SCAN *hashtab[HSIZE]; /* scanline hash table */ |
49 |
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50 |
greg |
1.2 |
static long ncall = 0L; /* number of calls to getpictscan */ |
51 |
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static long nread = 0L; /* number of scanlines read */ |
52 |
greg |
1.1 |
|
53 |
greg |
1.8 |
SCAN *scanretire(); |
54 |
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55 |
greg |
1.5 |
extern long ftell(); |
56 |
greg |
1.2 |
|
57 |
greg |
1.5 |
|
58 |
greg |
1.8 |
SCAN * |
59 |
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claimscan(y) /* claim scanline from buffers */ |
60 |
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int y; |
61 |
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{ |
62 |
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int hi = shash(y); |
63 |
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SCAN *slast; |
64 |
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register SCAN *sl; |
65 |
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66 |
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for (sl = hashtab[hi]; sl != NULL; sl = sl->next) |
67 |
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if (sl->y == y) /* active scanline */ |
68 |
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return(sl); |
69 |
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for (slast = NULL, sl = freelist; sl != NULL; slast = sl, sl = sl->next) |
70 |
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if (sl->y == -1 || sl->y == y || sl->next == NULL) { |
71 |
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if (slast == NULL) /* remove from free */ |
72 |
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freelist = sl->next; |
73 |
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else |
74 |
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slast->next = sl->next; |
75 |
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if (sl->y == y) { /* reclaim */ |
76 |
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sl->next = hashtab[hi]; |
77 |
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hashtab[hi] = sl; |
78 |
greg |
1.11 |
#ifdef DEBUG |
79 |
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if (verbose) |
80 |
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fprintf(stderr, |
81 |
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"%s: scanline %d reclaimed\n", |
82 |
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progname, y); |
83 |
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#endif |
84 |
greg |
1.8 |
} |
85 |
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return(sl); |
86 |
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} |
87 |
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return(scanretire()); /* need more free scanlines */ |
88 |
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} |
89 |
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90 |
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91 |
greg |
1.1 |
COLR * |
92 |
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getpictscan(y) /* get picture scanline */ |
93 |
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int y; |
94 |
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{ |
95 |
greg |
1.8 |
register SCAN *sl; |
96 |
greg |
1.1 |
register int i; |
97 |
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/* first check our buffers */ |
98 |
greg |
1.8 |
sl = claimscan(y); |
99 |
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if (sl == NULL) |
100 |
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memerr("claimscan()"); |
101 |
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sl->lused = ncall++; |
102 |
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if (sl->y == y) /* scan hit */ |
103 |
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return(scandata(sl)); |
104 |
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/* else read in replacement */ |
105 |
greg |
1.5 |
if (scanpos[y] < 0) { /* need to search */ |
106 |
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for (i = y+1; i < curpos; i++) |
107 |
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if (scanpos[i] >= 0) { |
108 |
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if (fseek(pictfp, scanpos[i], 0) < 0) |
109 |
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goto seekerr; |
110 |
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curpos = i; |
111 |
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break; |
112 |
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} |
113 |
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while (curpos >= y) { |
114 |
greg |
1.1 |
scanpos[curpos] = ftell(pictfp); |
115 |
greg |
1.8 |
if (freadcolrs(scandata(sl), pxsiz, pictfp) < 0) |
116 |
greg |
1.1 |
goto readerr; |
117 |
greg |
1.5 |
nread++; |
118 |
greg |
1.1 |
curpos--; |
119 |
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} |
120 |
greg |
1.5 |
} else { |
121 |
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if (curpos != y && fseek(pictfp, scanpos[y], 0) < 0) |
122 |
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goto seekerr; |
123 |
greg |
1.8 |
if (freadcolrs(scandata(sl), pxsiz, pictfp) < 0) |
124 |
greg |
1.5 |
goto readerr; |
125 |
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nread++; |
126 |
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curpos = y-1; |
127 |
greg |
1.1 |
} |
128 |
greg |
1.8 |
sl->y = y; |
129 |
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i = shash(y); /* add to hash list */ |
130 |
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sl->next = hashtab[i]; |
131 |
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hashtab[i] = sl; |
132 |
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return(scandata(sl)); |
133 |
greg |
1.1 |
readerr: |
134 |
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fprintf(stderr, "%s: picture read error\n", progname); |
135 |
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exit(1); |
136 |
greg |
1.5 |
seekerr: |
137 |
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fprintf(stderr, "%s: picture seek error\n", progname); |
138 |
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exit(1); |
139 |
greg |
1.1 |
} |
140 |
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141 |
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142 |
greg |
1.6 |
#ifdef DEBUG |
143 |
greg |
1.2 |
pict_stats() /* print out picture read statistics */ |
144 |
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{ |
145 |
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static long lastcall = 0L; /* ncall at last report */ |
146 |
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static long lastread = 0L; /* nread at last report */ |
147 |
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148 |
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if (ncall == lastcall) |
149 |
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return; |
150 |
greg |
1.6 |
fprintf(stderr, "%s: %ld scanlines read in %ld calls\n", |
151 |
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progname, nread-lastread, ncall-lastcall); |
152 |
greg |
1.2 |
lastcall = ncall; |
153 |
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lastread = nread; |
154 |
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} |
155 |
greg |
1.6 |
#endif |
156 |
greg |
1.2 |
|
157 |
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158 |
greg |
1.1 |
double |
159 |
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pict_val(vd) /* find picture value for view direction */ |
160 |
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FVECT vd; |
161 |
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{ |
162 |
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FVECT pp; |
163 |
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double vpx, vpy, vpz; |
164 |
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COLOR res; |
165 |
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166 |
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if (pictfp == NULL) |
167 |
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return(-1.0); |
168 |
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pp[0] = pictview.vp[0] + vd[0]; |
169 |
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pp[1] = pictview.vp[1] + vd[1]; |
170 |
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pp[2] = pictview.vp[2] + vd[2]; |
171 |
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viewpixel(&vpx, &vpy, &vpz, &pictview, pp); |
172 |
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if (vpz <= FTINY || vpx < 0. || vpx >= 1. || vpy < 0. || vpy >= 1.) |
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return(-1.0); |
174 |
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colr_color(res, getpictscan((int)(vpy*pysiz))[(int)(vpx*pxsiz)]); |
175 |
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return(luminance(res)/exposure); |
176 |
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} |
177 |
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178 |
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179 |
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double |
180 |
greg |
1.12 |
getviewpix(vh, vv, se) /* compute single view pixel */ |
181 |
greg |
1.1 |
int vh, vv; |
182 |
greg |
1.12 |
SPANERR *se; |
183 |
greg |
1.1 |
{ |
184 |
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FVECT dir; |
185 |
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float rt_buf[6]; |
186 |
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double res; |
187 |
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188 |
greg |
1.12 |
if (compdir(dir, vh, vv, se) < 0) |
189 |
greg |
1.1 |
return(-1.0); |
190 |
greg |
1.7 |
npixinvw++; |
191 |
greg |
1.1 |
if ((res = pict_val(dir)) >= 0.0) |
192 |
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return(res); |
193 |
greg |
1.7 |
if (rt_pid == -1) { |
194 |
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npixmiss++; |
195 |
greg |
1.1 |
return(-1.0); |
196 |
greg |
1.7 |
} |
197 |
greg |
1.1 |
rt_buf[0] = ourview.vp[0]; |
198 |
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rt_buf[1] = ourview.vp[1]; |
199 |
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rt_buf[2] = ourview.vp[2]; |
200 |
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rt_buf[3] = dir[0]; |
201 |
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rt_buf[4] = dir[1]; |
202 |
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rt_buf[5] = dir[2]; |
203 |
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rt_compute(rt_buf, 1); |
204 |
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return(luminance(rt_buf)); |
205 |
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} |
206 |
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207 |
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208 |
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getviewspan(vv, vb) /* compute a span of view pixels */ |
209 |
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int vv; |
210 |
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float *vb; |
211 |
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{ |
212 |
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float rt_buf[6*MAXPIX]; /* rtrace send/receive buffer */ |
213 |
greg |
1.3 |
register int n; /* number of pixels in buffer */ |
214 |
greg |
1.1 |
short buf_vh[MAXPIX]; /* pixel positions */ |
215 |
greg |
1.12 |
SPANERR sperr; |
216 |
greg |
1.1 |
FVECT dir; |
217 |
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register int vh; |
218 |
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219 |
greg |
1.4 |
#ifdef DEBUG |
220 |
greg |
1.1 |
if (verbose) |
221 |
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fprintf(stderr, "%s: computing view span at %d...\n", |
222 |
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progname, vv); |
223 |
greg |
1.4 |
#endif |
224 |
greg |
1.12 |
setspanerr(&sperr, vv); |
225 |
greg |
1.3 |
n = 0; |
226 |
greg |
1.1 |
for (vh = -hsize; vh <= hsize; vh++) { |
227 |
greg |
1.12 |
if (compdir(dir, vh, vv, &sperr) < 0) { /* not in view */ |
228 |
greg |
1.1 |
vb[vh+hsize] = -1.0; |
229 |
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continue; |
230 |
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} |
231 |
greg |
1.7 |
npixinvw++; |
232 |
greg |
1.1 |
if ((vb[vh+hsize] = pict_val(dir)) >= 0.0) |
233 |
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continue; |
234 |
greg |
1.7 |
if (rt_pid == -1) { /* missing information */ |
235 |
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npixmiss++; |
236 |
greg |
1.1 |
continue; |
237 |
greg |
1.7 |
} |
238 |
greg |
1.1 |
/* send to rtrace */ |
239 |
greg |
1.3 |
if (n >= MAXPIX) { /* flush */ |
240 |
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rt_compute(rt_buf, n); |
241 |
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while (n-- > 0) |
242 |
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vb[buf_vh[n]+hsize] = luminance(rt_buf+3*n); |
243 |
greg |
1.1 |
} |
244 |
greg |
1.3 |
rt_buf[6*n] = ourview.vp[0]; |
245 |
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rt_buf[6*n+1] = ourview.vp[1]; |
246 |
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rt_buf[6*n+2] = ourview.vp[2]; |
247 |
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rt_buf[6*n+3] = dir[0]; |
248 |
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rt_buf[6*n+4] = dir[1]; |
249 |
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rt_buf[6*n+5] = dir[2]; |
250 |
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buf_vh[n++] = vh; |
251 |
greg |
1.1 |
} |
252 |
greg |
1.4 |
#ifdef DEBUG |
253 |
greg |
1.2 |
if (verbose) |
254 |
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pict_stats(); |
255 |
greg |
1.4 |
#endif |
256 |
greg |
1.3 |
if (n > 0) { /* process pending buffer */ |
257 |
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rt_compute(rt_buf, n); |
258 |
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while (n-- > 0) |
259 |
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vb[buf_vh[n]+hsize] = luminance(rt_buf+3*n); |
260 |
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} |
261 |
greg |
1.1 |
} |
262 |
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263 |
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264 |
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rt_compute(pb, np) /* process buffer through rtrace */ |
265 |
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float *pb; |
266 |
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int np; |
267 |
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{ |
268 |
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static float nbuf[6] = {0.,0.,0.,0.,0.,0.}; |
269 |
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270 |
greg |
1.4 |
#ifdef DEBUG |
271 |
greg |
1.1 |
if (verbose && np > 1) |
272 |
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fprintf(stderr, "%s: sending %d samples to rtrace...\n", |
273 |
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progname, np); |
274 |
greg |
1.4 |
#endif |
275 |
greg |
1.1 |
if (writebuf(fd_tort,(char *)pb,6*sizeof(float)*np) < 6*sizeof(float)*np |
276 |
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|| writebuf(fd_tort,(char *)nbuf,sizeof(nbuf)) < sizeof(nbuf)) { |
277 |
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fprintf(stderr, "%s: error writing to rtrace process\n", |
278 |
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progname); |
279 |
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exit(1); |
280 |
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} |
281 |
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if (readbuf(fd_fromrt, (char *)pb, 3*sizeof(float)*np) |
282 |
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< 3*sizeof(float)*np) { |
283 |
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fprintf(stderr, "%s: error reading from rtrace process\n", |
284 |
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progname); |
285 |
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exit(1); |
286 |
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} |
287 |
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} |
288 |
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289 |
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290 |
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getexpos(s) /* get exposure from header line */ |
291 |
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char *s; |
292 |
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{ |
293 |
|
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if (isexpos(s)) |
294 |
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exposure *= exposval(s); |
295 |
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} |
296 |
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297 |
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298 |
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open_pict(fn) /* open picture file */ |
299 |
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char *fn; |
300 |
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{ |
301 |
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if ((pictfp = fopen(fn, "r")) == NULL) { |
302 |
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fprintf("%s: cannot open\n", fn); |
303 |
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exit(1); |
304 |
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} |
305 |
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exposure = 1.0; |
306 |
|
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getheader(pictfp, getexpos); |
307 |
|
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if (fgetresolu(&pxsiz, &pysiz, pictfp) != (YMAJOR|YDECR)) { |
308 |
|
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fprintf("%s: bad picture resolution\n", fn); |
309 |
|
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exit(1); |
310 |
|
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} |
311 |
greg |
1.8 |
initscans(); |
312 |
greg |
1.1 |
} |
313 |
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314 |
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315 |
|
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close_pict() /* done with picture */ |
316 |
|
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{ |
317 |
|
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if (pictfp == NULL) |
318 |
|
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return; |
319 |
|
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fclose(pictfp); |
320 |
greg |
1.8 |
donescans(); |
321 |
greg |
1.1 |
pictfp = NULL; |
322 |
|
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} |
323 |
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324 |
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|
325 |
|
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fork_rtrace(av) /* open pipe and start rtrace */ |
326 |
|
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char *av[]; |
327 |
|
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{ |
328 |
|
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int p0[2], p1[2]; |
329 |
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|
330 |
|
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if (pipe(p0) < 0 || pipe(p1) < 0) { |
331 |
|
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perror(progname); |
332 |
|
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exit(1); |
333 |
|
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} |
334 |
|
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if ((rt_pid = vfork()) == 0) { /* if child */ |
335 |
|
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close(p0[1]); |
336 |
|
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close(p1[0]); |
337 |
|
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if (p0[0] != 0) { /* connect p0 to stdin */ |
338 |
|
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dup2(p0[0], 0); |
339 |
|
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close(p0[0]); |
340 |
|
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} |
341 |
|
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if (p1[1] != 0) { /* connect p1 to stdout */ |
342 |
|
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dup2(p1[1], 1); |
343 |
|
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close(p1[1]); |
344 |
|
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} |
345 |
|
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execvp(av[0], av); |
346 |
|
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perror(av[0]); |
347 |
|
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_exit(127); |
348 |
|
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} |
349 |
|
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if (rt_pid == -1) { |
350 |
|
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perror(progname); |
351 |
|
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exit(1); |
352 |
|
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} |
353 |
greg |
1.3 |
close(p0[0]); |
354 |
|
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close(p1[1]); |
355 |
greg |
1.1 |
fd_tort = p0[1]; |
356 |
|
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fd_fromrt = p1[0]; |
357 |
|
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} |
358 |
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|
359 |
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|
360 |
|
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done_rtrace() /* wait for rtrace to finish */ |
361 |
|
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{ |
362 |
|
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int pid, status; |
363 |
|
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|
364 |
|
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if (rt_pid == -1) |
365 |
|
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return; |
366 |
|
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close(fd_tort); |
367 |
|
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close(fd_fromrt); |
368 |
|
|
while ((pid = wait(&status)) != -1 && pid != rt_pid) |
369 |
|
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; |
370 |
|
|
if (pid == rt_pid && status != 0) { |
371 |
|
|
fprintf(stderr, "%s: bad status (%d) from rtrace\n", |
372 |
|
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progname, status); |
373 |
|
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exit(1); |
374 |
|
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} |
375 |
|
|
rt_pid = -1; |
376 |
|
|
} |
377 |
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|
378 |
|
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|
379 |
|
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int |
380 |
|
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readbuf(fd, bpos, siz) |
381 |
|
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int fd; |
382 |
|
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char *bpos; |
383 |
|
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int siz; |
384 |
|
|
{ |
385 |
|
|
register int cc, nrem = siz; |
386 |
|
|
|
387 |
|
|
while (nrem > 0 && (cc = read(fd, bpos, nrem)) > 0) { |
388 |
|
|
bpos += cc; |
389 |
|
|
nrem -= cc; |
390 |
|
|
} |
391 |
|
|
if (cc < 0) |
392 |
|
|
return(cc); |
393 |
|
|
return(siz-nrem); |
394 |
|
|
} |
395 |
|
|
|
396 |
|
|
|
397 |
|
|
int |
398 |
|
|
writebuf(fd, bpos, siz) |
399 |
|
|
char *bpos; |
400 |
|
|
int siz; |
401 |
|
|
{ |
402 |
|
|
register int cc, nrem = siz; |
403 |
|
|
|
404 |
|
|
while (nrem > 0 && (cc = write(fd, bpos, nrem)) > 0) { |
405 |
|
|
bpos += cc; |
406 |
|
|
nrem -= cc; |
407 |
|
|
} |
408 |
|
|
if (cc < 0) |
409 |
|
|
return(cc); |
410 |
|
|
return(siz-nrem); |
411 |
greg |
1.8 |
} |
412 |
|
|
|
413 |
|
|
|
414 |
|
|
SCAN * |
415 |
|
|
scanretire() /* retire old scanlines to free list */ |
416 |
|
|
{ |
417 |
|
|
SCAN *sold[NRETIRE]; |
418 |
|
|
int n; |
419 |
|
|
int h; |
420 |
|
|
register SCAN *sl; |
421 |
|
|
register int i; |
422 |
|
|
/* grab the NRETIRE oldest scanlines */ |
423 |
|
|
sold[n = 0] = NULL; |
424 |
greg |
1.10 |
for (h = 0; h < HSIZE; h++) |
425 |
|
|
for (sl = hashtab[h]; sl != NULL; sl = sl->next) { |
426 |
|
|
for (i = n; i && sold[i-1]->lused > sl->lused; i--) |
427 |
|
|
if (i < NRETIRE) |
428 |
greg |
1.8 |
sold[i] = sold[i-1]; |
429 |
|
|
if (i < NRETIRE) { |
430 |
greg |
1.10 |
sold[i] = sl; |
431 |
greg |
1.8 |
if (n < NRETIRE) /* grow list */ |
432 |
|
|
n++; |
433 |
greg |
1.10 |
} |
434 |
|
|
} |
435 |
|
|
/* put scanlines into free list */ |
436 |
|
|
for (i = 0; i < n; i++) { |
437 |
|
|
h = shash(sold[i]->y); |
438 |
|
|
sl = hashtab[h]; |
439 |
|
|
if (sl == sold[i]) |
440 |
|
|
hashtab[h] = sl->next; |
441 |
|
|
else { |
442 |
|
|
while (sl->next != sold[i]) /* IS in list */ |
443 |
greg |
1.8 |
sl = sl->next; |
444 |
greg |
1.10 |
sl->next = sold[i]->next; |
445 |
greg |
1.8 |
} |
446 |
greg |
1.10 |
if (i > 0) { /* save oldest as return value */ |
447 |
|
|
sold[i]->next = freelist; |
448 |
|
|
freelist = sold[i]; |
449 |
|
|
} |
450 |
greg |
1.8 |
} |
451 |
|
|
return(sold[0]); |
452 |
|
|
} |
453 |
|
|
|
454 |
|
|
|
455 |
|
|
static char *scan_buf; |
456 |
|
|
|
457 |
|
|
|
458 |
|
|
initscans() /* initialize scanline buffers */ |
459 |
|
|
{ |
460 |
|
|
int scansize; |
461 |
|
|
register SCAN *ptr; |
462 |
|
|
register int i; |
463 |
|
|
/* initialize positions */ |
464 |
|
|
scanpos = (long *)malloc(pysiz*sizeof(long)); |
465 |
|
|
if (scanpos == NULL) |
466 |
|
|
memerr("scanline positions"); |
467 |
|
|
for (i = pysiz-1; i >= 0; i--) |
468 |
|
|
scanpos[i] = -1L; |
469 |
|
|
curpos = pysiz-1; |
470 |
|
|
/* clear hash table */ |
471 |
|
|
for (i = 0; i < HSIZE; i++) |
472 |
|
|
hashtab[i] = NULL; |
473 |
|
|
/* allocate scanline buffers */ |
474 |
|
|
scansize = sizeof(SCAN) + pxsiz*sizeof(COLR); |
475 |
|
|
#ifdef ALIGN |
476 |
|
|
scansize = scansize+(sizeof(ALIGN)-1)) & ~(sizeof(ALIGN)-1); |
477 |
|
|
#endif |
478 |
|
|
i = MAXSBUF / scansize; /* compute number to allocate */ |
479 |
|
|
if (i > HSIZE) |
480 |
|
|
i = HSIZE; |
481 |
|
|
scan_buf = malloc(i*scansize); /* get in one big chunk */ |
482 |
|
|
if (scan_buf == NULL) |
483 |
|
|
memerr("scanline buffers"); |
484 |
|
|
ptr = (SCAN *)scan_buf; |
485 |
|
|
freelist = NULL; /* build our free list */ |
486 |
|
|
while (i-- > 0) { |
487 |
|
|
ptr->y = -1; |
488 |
|
|
ptr->lused = -1; |
489 |
|
|
ptr->next = freelist; |
490 |
|
|
freelist = ptr; |
491 |
|
|
ptr = (SCAN *)((char *)ptr + scansize); /* beware of C bugs */ |
492 |
|
|
} |
493 |
|
|
} |
494 |
|
|
|
495 |
|
|
|
496 |
|
|
donescans() /* free up scanlines */ |
497 |
|
|
{ |
498 |
|
|
free(scan_buf); |
499 |
|
|
free((char *)scanpos); |
500 |
greg |
1.1 |
} |