diff options
Diffstat (limited to 'third_party/spiro/font/segment.c')
| -rw-r--r-- | third_party/spiro/font/segment.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/third_party/spiro/font/segment.c b/third_party/spiro/font/segment.c new file mode 100644 index 0000000..8eb6b06 --- /dev/null +++ b/third_party/spiro/font/segment.c @@ -0,0 +1,194 @@ +#include <string.h> +#include <stdio.h> +#include <stdlib.h> + +#define MIN(a,b) ((a) < (b) ? (a) : (b)) +#define MAX(a,b) ((a) > (b) ? (a) : (b)) + +typedef struct { + int x0; + int x1; + int y0; + int y1; + double xmom; + double ymom; + int area; +} seg; + +typedef struct { + int x0; + int x1; +} run; + +void +find_runs(run *result, const unsigned char *buf, unsigned char thresh, int xs) +{ + int x; + int j = 0; + + for (x = 0; x < xs;) { + int x0, x1; + for (x0 = x; x0 < xs; x0++) + if (buf[x0] < thresh) + break; + if (x0 == xs) + break; + for (x1 = x0 + 1; x1 < xs; x1++) + if (buf[x1] >= thresh) + break; + result[j].x0 = x0; + result[j].x1 = x1; + j++; + x = x1 + 1; + } + result[j].x0 = 0; + result[j].x1 = 0; +} + +void +print_rect(const seg *r) +{ + printf("%d %d %d %d %g rect\n", r->x0, r->y0, r->x1, r->y1, + r->area / (1.0 * (r->x1 - r->x0) * (r->y1 - r->y0))); + printf("%g %g ci\n", r->xmom / r->area, r->ymom / r->area); +} + +void +merge_runs(seg *buf, const run *new_runs, int y) +{ + int bi, ni; + int bs; + int bi0; + int flag; + + for (bs = 0; buf[bs].x1; bs++); + + bi = 0; + flag = 1; + for (ni = 0; new_runs[ni].x1; ni++) { + int run_len = new_runs[ni].x1 - new_runs[ni].x0; + + bi0 = bi; + for (; bi < bs && buf[bi].x1 <= new_runs[ni].x0; bi++) { + if (flag) { + buf[bi].y1 = y; + print_rect(&buf[bi]); + } else { + bi0 = bi + 1; + flag = 1; + } + } + if (bi > bi0) { + memmove(&buf[bi0], &buf[bi], (bs - bi) * sizeof(seg)); + bs += bi0 - bi; + } + bi = bi0; + if (bi < bs && buf[bi].x0 < new_runs[ni].x1) { + double xmom = buf[bi].xmom; + double ymom = buf[bi].ymom; + int area = buf[bi].area; + int y0 = buf[bi].y0; + + for (bi = bi + 1; bi < bs && buf[bi].x0 < new_runs[ni].x1; bi++) { + y0 = MIN(y0, buf[bi].y0); + xmom += buf[bi].xmom; + ymom += buf[bi].ymom; + area += buf[bi].area; + } + buf[bi0].x0 = MIN(buf[bi0].x0, new_runs[ni].x0); + buf[bi0].x1 = MAX(buf[bi - 1].x1, new_runs[ni].x1); + buf[bi0].y0 = y0; + buf[bi0].xmom = xmom + run_len * .5 * (new_runs[ni].x0 + new_runs[ni].x1); + buf[bi0].ymom = ymom + run_len * y; + buf[bi0].area = area + run_len; + if (bi > bi0 + 1) { + memmove(&buf[bi0 + 1], &buf[bi], (bs - bi) * sizeof(seg)); + bs += bi0 + 1 - bi; + } + bi = bi0; + flag = 0; + } else { + memmove(&buf[bi + 1], &buf[bi], (bs - bi) * sizeof(seg)); + bs++; + buf[bi].x0 = new_runs[ni].x0; + buf[bi].x1 = new_runs[ni].x1; + buf[bi].y0 = y; + buf[bi].xmom = run_len * .5 * (new_runs[ni].x0 + new_runs[ni].x1); + buf[bi].ymom = run_len * y; + buf[bi].area = run_len; + bi++; + flag = 1; + } + } + bi0 = bi; + for (; bi < bs; bi++) { + if (flag) { + buf[bi].y1 = y; + print_rect(&buf[bi]); + } else { + bi0 = bi + 1; + flag = 1; + } + } + buf[bi0].x0 = 0; + buf[bi0].x1 = 0; +} + +static void +die (char *why) +{ + fprintf (stderr, "%s\n", why); + exit (1); +} + +#define MAX_SIZE 65536 + +int +main (int argc, char **argv) +{ + FILE *fi = stdin; + FILE *fo = stdout; + char buf[256]; + int xs, ys; + int depth; + unsigned char *imgbuf; + seg *segs; + run *runs; + int y; + + fgets (buf, sizeof(buf), fi); + if (buf[0] != 'P' || buf[1] != '5') + die ("Need pgmraw image on input"); + + xs = ys = 0; + do + fgets (buf, sizeof(buf), fi); + while (buf[0] == '#'); + sscanf (buf, "%d %d", &xs, &ys); + if (xs <= 0 || ys <= 0 || xs > MAX_SIZE || ys > MAX_SIZE) + die ("Input image size out of range"); + + do + fgets (buf, sizeof(buf), fi); + while (buf[0] == '#'); + sscanf (buf, "%d", &depth); + if (depth != 255) + die ("Only works with depth=255 images"); + + runs = (run *)malloc(((xs + 3) >> 1) * sizeof(run)); + segs = (seg *)malloc(((xs + 3) >> 1) * sizeof(seg)); + imgbuf = (unsigned char *)malloc (xs); + segs[0].x0 = 0; + segs[0].x1 = 0; + for (y = 0; y < ys; y++) { + fread (imgbuf, 1, xs, fi); + find_runs(runs, imgbuf, 160, xs); + merge_runs(segs, runs, y); + } + + free(imgbuf); + free(runs); + free(segs); + + return 0; +} |