#include <stdio.h>
#include <stdlib.h>
+#include <string.h>
#include <stdint.h>
#include <math.h>
struct vec2 {
- float x, y;
+ int x, y;
};
int main(int argc, char **argv)
{
- int i, j, imgrad, xsz = 240, ysz = 160, texsz = 128;
+ int i, j, frm, imgrad, out_nlines, xsz = 240, ysz = 160, texsz = 128;
+ int half_y = 0;
+ int center = 0;
struct vec2 *tunbuf, *tun;
- float aspect, prev_r;
+ float prev_r;
struct vec2 *buf, *ptr;
+ char *endp;
+ int num_frames = 1;
for(i=1; i<argc; i++) {
if(argv[i][0] == '-') {
}
break;
+ case 'y':
+ half_y = 1;
+ break;
+
+ case 'c':
+ if(!argv[++i]) {
+ fprintf(stderr, "-c must be followed by a center pixel\n");
+ return 1;
+ }
+ center = strtol(argv[i], &endp, 10);
+ if(endp == argv[i]) {
+ fprintf(stderr, "-c invalid center position: %s\n", argv[i]);
+ return 1;
+ }
+ break;
+
+ case 'n':
+ if(!argv[++i]) {
+ fprintf(stderr, "-n must be followed by the number of frames\n");
+ return 1;
+ }
+ if(!(num_frames = atoi(argv[i]))) {
+ fprintf(stderr, "-n invalid number of frames: %s\n", argv[i]);
+ return 1;
+ }
+ break;
+
default:
goto invalopt;
}
}
}
+ out_nlines = half_y ? ysz / 2 : ysz;
+
if(!(buf = malloc(xsz * ysz * sizeof *buf))) {
perror("failed to allocate buffer");
return 1;
}
imgrad = sqrt(xsz * xsz + ysz * ysz);
+ FILE *fp = fopen("tun_preview.ppm", "wb");
+ if(fp) {
+ fprintf(fp, "P6\n%d %d\n255\n", xsz, out_nlines * num_frames);
+ }
+
+
+ for(frm=0; frm<num_frames; frm++) {
+ int coffs = num_frames > 1 ? frm * center / (num_frames - 1) : center;
+
+ memset(buf, 0xff, xsz * ysz * sizeof *buf);
+
#define UDIV 2048
#define VDIV 32768
- prev_r = 0.0f;
- for(i=0; i<VDIV; i++) {
- float v = (float)(VDIV - i) / (float)VDIV;
- float r = 4.0 / v + 16;
- float z = v * 400.0f;
-
- /* don't bother drawing rings < 1 pixel apart */
- if(fabs(r - prev_r) < 0.05) continue;
-
- for(j=0; j<UDIV; j++) {
- float u = (float)j / (float)(UDIV - 1);
- float theta = 2.0f * u * M_PI;
-
- int x = (int)(cos(theta) * r - z) + xsz / 2;
- int y = (int)(sin(theta) * r) + ysz / 2;
-
- if(x >= 0 && x < xsz && y >= 0 && y < ysz) {
- ptr = buf + y * xsz + x;
- ptr->x = u;
- ptr->y = v * 8;
+ prev_r = 0.0f;
+#pragma omp parallel for private(i, j, prev_r, ptr) schedule(dynamic)
+ for(i=0; i<VDIV; i++) {
+ float v = (float)(VDIV - i) / (float)VDIV;
+ float r = 4.0 / v + 16;
+ float z = v * coffs;
+
+ /* don't bother drawing rings < 1 pixel apart */
+ if(r < 0 || fabs(r - prev_r) < 0.05) continue;
+
+ for(j=0; j<UDIV; j++) {
+ float u = (float)j / (float)(UDIV - 1);
+ float theta = 2.0f * u * M_PI;
+
+ int x = (int)(cos(theta) * r - z) + xsz / 2;
+ int y = (int)(sin(theta) * r) + ysz / 2;
+
+ if(x >= 0 && x < xsz && y >= 0 && y < ysz) {
+ ptr = buf + y * xsz + x;
+ ptr->x = (j << 8) / UDIV;
+ ptr->y = ((VDIV - i) << 11) / VDIV;
+ }
}
+ prev_r = r;
}
- prev_r = r;
- }
- FILE *fp = fopen("tun_preview.ppm", "wb");
- if(fp) {
- fprintf(fp, "P6\n%d %d\n255\n", xsz, ysz);
- }
+ ptr = buf;
+ for(i=0; i<out_nlines; i++) {
+ for(j=0; j<xsz; j++) {
+ int u = ptr->x;
+ int v = ptr->y;
+ int r = (u << 3) & 0xff;
+ int g = (v >> 3) & 0xff;
- aspect = (float)xsz / (float)ysz;
+ /*if(v > 2.0) r = g = b = 0;*/
- ptr = buf;
- for(i=0; i<ysz; i++) {
- for(j=0; j<xsz; j++) {
- float u = ptr->x;
- float v = ptr->y;
- int r = (int)(u * 8.0 * 255.0f) & 0xff;
- int b = (int)(v * 8.0 * 255.0f) & 0xff;
+ ptr++;
- ptr++;
+ uint16_t out = ((uint16_t)u & 0x3f) | (((uint16_t)v & 0x3ff) << 6);
+ fwrite(&out, sizeof out, 1, stdout);
- uint16_t out = ((uint16_t)(u * 255.0f) & 0xff) |
- (((uint16_t)(v * 255.0f) & 0xff) << 8);
- fwrite(&out, sizeof out, 1, stdout);
-
- if(fp) {
- fputc(r, fp);
- fputc(0, fp);
- fputc(b, fp);
+ if(fp) {
+ fputc(r, fp);
+ fputc(g, fp);
+ fputc(0, fp);
+ }
}
}
+
}
fflush(stdout);
projects / gbajam21 / blobdiff