wonky sweep
[gbajam21] / tools / tungen.c
index ec21217..49b3f16 100644 (file)
@@ -9,10 +9,14 @@ struct vec2 {
 
 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] == '-') {
@@ -32,6 +36,33 @@ int main(int argc, char **argv)
                                }
                                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;
                        }
@@ -41,71 +72,78 @@ invalopt:   fprintf(stderr, "invalid argument: %s\n", argv[i]);
                }
        }
 
+       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);
 
-#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 = 1.5 / v + 16;
-               float z = v * 200.0f;
-
-               /* 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 = r;
-       }
-
        FILE *fp = fopen("tun_preview.ppm", "wb");
        if(fp) {
-               fprintf(fp, "P6\n%d %d\n255\n", xsz, ysz);
+               fprintf(fp, "P6\n%d %d\n255\n", xsz, out_nlines * num_frames);
        }
 
-       aspect = (float)xsz / (float)ysz;
-
-       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 g = (int)(v * 8.0 * 255.0f) & 0xff;
-                       int b = (~(int)(v * 0.5 * 255.0f) & 0xff) + 105;
-                       if(b > 255) b = 255;
-                       if(b < 0) b = 0;
-
-                       /*if(v > 2.0) r = g = b = 0;*/
 
-                       ptr++;
+       for(frm=0; frm<num_frames; frm++) {
+               int coffs = num_frames > 1 ? frm * center / (num_frames - 1) : center;
 
-                       uint16_t out = ((uint16_t)(u * 255.0f) & 0xff) |
-                               (((uint16_t)(v * 255.0f) & 0xff) << 8);
-                       fwrite(&out, sizeof out, 1, stdout);
+#define UDIV   2048
+#define VDIV   32768
+               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(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 = r;
+               }
 
-                       if(fp) {
-                               fputc(r, fp);
-                               fputc(g, fp);
-                               fputc(b, fp);
+               ptr = buf;
+               for(i=0; i<out_nlines; 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 g = (int)(v * 8.0 * 255.0f) & 0xff;
+                               int b = (~(int)(v * 0.5 * 255.0f) & 0xff) + 105;
+                               if(b > 255) b = 255;
+                               if(b < 0) b = 0;
+
+                               /*if(v > 2.0) r = g = b = 0;*/
+
+                               ptr++;
+
+                               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(g, fp);
+                                       fputc(b, fp);
+                               }
                        }
                }
+
        }
        fflush(stdout);