| 39 |  | static long     ncall = 0L;     /* number of calls to getpictscan */ | 
| 40 |  | static long     nread = 0L;     /* number of scanlines read */ | 
| 41 |  |  | 
| 42 | + | extern long     ftell(); | 
| 43 |  |  | 
| 44 | + |  | 
| 45 |  | COLR * | 
| 46 |  | getpictscan(y)                  /* get picture scanline */ | 
| 47 |  | int     y; | 
| 48 |  | { | 
| 47 | – | extern long     ftell(); | 
| 49 |  | int     minused; | 
| 50 |  | register int    i; | 
| 51 |  | /* first check our buffers */ | 
| 60 |  | minused = i; | 
| 61 |  | } | 
| 62 |  | /* not there, read it in */ | 
| 63 | < | if (scanpos[y] == -1) {                 /* need to search */ | 
| 64 | < | while (curpos > y) { | 
| 63 | > | if (scanpos[y] < 0) {                   /* need to search */ | 
| 64 | > | for (i = y+1; i < curpos; i++) | 
| 65 | > | if (scanpos[i] >= 0) { | 
| 66 | > | if (fseek(pictfp, scanpos[i], 0) < 0) | 
| 67 | > | goto seekerr; | 
| 68 | > | curpos = i; | 
| 69 | > | break; | 
| 70 | > | } | 
| 71 | > | while (curpos >= y) { | 
| 72 |  | scanpos[curpos] = ftell(pictfp); | 
| 73 |  | if (freadcolrs(scan[minused].sl, pxsiz, pictfp) < 0) | 
| 74 |  | goto readerr; | 
| 75 | + | nread++; | 
| 76 |  | curpos--; | 
| 77 |  | } | 
| 78 | < | } else if (fseek(pictfp, scanpos[y], 0) < 0) { | 
| 79 | < | fprintf(stderr, "%s: picture seek error\n", progname); | 
| 80 | < | exit(1); | 
| 78 | > | } else { | 
| 79 | > | if (curpos != y && fseek(pictfp, scanpos[y], 0) < 0) | 
| 80 | > | goto seekerr; | 
| 81 | > | if (freadcolrs(scan[minused].sl, pxsiz, pictfp) < 0) | 
| 82 | > | goto readerr; | 
| 83 | > | nread++; | 
| 84 | > | curpos = y-1; | 
| 85 |  | } | 
| 73 | – | if (freadcolrs(scan[minused].sl, pxsiz, pictfp) < 0) | 
| 74 | – | goto readerr; | 
| 75 | – | nread++; | 
| 76 | – | curpos = y-1; | 
| 86 |  | scan[minused].lused = ncall; | 
| 87 |  | scan[minused].y = y; | 
| 88 |  | return(scan[minused].sl); | 
| 89 |  | readerr: | 
| 90 |  | fprintf(stderr, "%s: picture read error\n", progname); | 
| 91 |  | exit(1); | 
| 92 | + | seekerr: | 
| 93 | + | fprintf(stderr, "%s: picture seek error\n", progname); | 
| 94 | + | exit(1); | 
| 95 |  | } | 
| 96 |  |  | 
| 97 |  |  | 
| 98 | + | #ifdef DEBUG | 
| 99 |  | pict_stats()                    /* print out picture read statistics */ | 
| 100 |  | { | 
| 101 |  | static long     lastcall = 0L;  /* ncall at last report */ | 
| 103 |  |  | 
| 104 |  | if (ncall == lastcall) | 
| 105 |  | return; | 
| 106 | < | fprintf(stderr, "%s: %ld scanlines read, %ld reused\n", | 
| 107 | < | progname, nread-lastread, | 
| 95 | < | (ncall-lastcall)-(nread-lastread)); | 
| 106 | > | fprintf(stderr, "%s: %ld scanlines read in %ld calls\n", | 
| 107 | > | progname, nread-lastread, ncall-lastcall); | 
| 108 |  | lastcall = ncall; | 
| 109 |  | lastread = nread; | 
| 110 |  | } | 
| 111 | + | #endif | 
| 112 |  |  | 
| 113 |  |  | 
| 114 |  | double | 
| 260 |  | scanpos = (long *)malloc(pysiz*sizeof(long)); | 
| 261 |  | if (scanpos == NULL) | 
| 262 |  | memerr("scanline positions"); | 
| 263 | < | for (i = 0; i < pysiz; i++) | 
| 263 | > | for (i = pysiz-1; i >= 0; i--) | 
| 264 |  | scanpos[i] = -1L; | 
| 265 | + | curpos = pysiz-1; | 
| 266 |  | for (i = 0; i < NSCANS; i++) { | 
| 267 |  | scan[i].lused = -1; | 
| 268 |  | scan[i].y = -1; | 
| 270 |  | if (scan[i].sl == NULL) | 
| 271 |  | memerr("scanline buffers"); | 
| 272 |  | } | 
| 259 | – | curpos = pysiz-1; | 
| 273 |  | } | 
| 274 |  |  | 
| 275 |  |  |