ref: 0f8168038af32828fcdc39575dea0e4de0c01122
dir: /sys/src/cmd/scat/image.c/
#include <u.h> #include <libc.h> #include <bio.h> #include "sky.h" char rad28[] = "0123456789abcdefghijklmnopqr"; Picture* image(Angle ra, Angle dec, Angle wid, Angle hig) { Pix *p; uchar *b, *up; int i, j, sx, sy, x, y; char file[50]; Picture *pic; Img* ip; int lowx, lowy, higx, higy; int slowx, slowy, shigx, shigy; Header *h; Angle d, bd; Plate *pp, *bp; if(gam.gamma == 0) gam.gamma = -1; if(gam.max == gam.min) { gam.max = 17600; gam.min = 2500; } gam.absgamma = gam.gamma; gam.neg = 0; if(gam.absgamma < 0) { gam.absgamma = -gam.absgamma; gam.neg = 1; } gam.mult1 = 1. / (gam.max - gam.min); gam.mult2 = 255. * gam.mult1; if(nplate == 0) getplates(); bp = 0; bd = 0; for(i=0; i<nplate; i++) { pp = &plate[i]; d = dist(ra, dec, pp->ra, pp->dec); if(bp == 0 || d < bd) { bp = pp; bd = d; } } if(debug) Bprint(&bout, "best plate: %s %s disk %d %s\n", hms(bp->ra), dms(bp->dec), bp->disk, bp->rgn); h = getheader(bp->rgn); xypos(h, ra, dec, 0, 0); if(wid <= 0 || hig <= 0) { lowx = h->x; lowy = h->y; lowx = (lowx/500) * 500; lowy = (lowy/500) * 500; higx = lowx + 500; higy = lowy + 500; } else { lowx = h->x - wid*ARCSECONDS_PER_RADIAN*1000 / (h->param[Pxpixelsz]*h->param[Ppltscale]*2); lowy = h->y - hig*ARCSECONDS_PER_RADIAN*1000 / (h->param[Pypixelsz]*h->param[Ppltscale]*2); higx = h->x + wid*ARCSECONDS_PER_RADIAN*1000 / (h->param[Pxpixelsz]*h->param[Ppltscale]*2); higy = h->y + hig*ARCSECONDS_PER_RADIAN*1000 / (h->param[Pypixelsz]*h->param[Ppltscale]*2); } free(h); if(lowx < 0) lowx = 0; if(higx < 0) higx = 0; if(lowy < 0) lowy = 0; if(higy < 0) higy = 0; if(lowx > 14000) lowx = 14000; if(higx > 14000) higx = 14000; if(lowy > 14000) lowy = 14000; if(higy > 14000) higy = 14000; if(debug) Bprint(&bout, "xy on plate: %d,%d %d,%d\n", lowx,lowy, higx, higy); if(lowx >= higx || lowy >=higy) { Bprint(&bout, "no image found\n"); return 0; } b = malloc((higx-lowx)*(higy-lowy)*sizeof(*b)); if(b == 0) { emalloc: fprint(2, "malloc error\n"); return 0; } memset(b, 0, (higx-lowx)*(higy-lowy)*sizeof(*b)); slowx = lowx/500; shigx = (higx-1)/500; slowy = lowy/500; shigy = (higy-1)/500; for(sx=slowx; sx<=shigx; sx++) for(sy=slowy; sy<=shigy; sy++) { if(sx < 0 || sx >= nelem(rad28) || sy < 0 || sy >= nelem(rad28)) { fprint(2, "bad subplate %d %d\n", sy, sx); free(b); return 0; } sprint(file, "%s/%s/%s.%c%c", dssmount(bp->disk), bp->rgn, bp->rgn, rad28[sy], rad28[sx]); ip = dssread(file); if(ip == 0) { fprint(2, "can't read %s: %r\n", file); free(b); return 0; } x = sx*500; y = sy*500; for(j=0; j<ip->ny; j++) { if(y+j < lowy || y+j >= higy) continue; p = &ip->a[j*ip->ny]; up = b + (higy - (y+j+1))*(higx-lowx) + (x - lowx); for(i=0; i<ip->nx; i++) { if(x+i >= lowx && x+i < higx) *up = dogamma(*p); up++; p += 1; } } free(ip); } pic = malloc(sizeof(Picture)); if(pic == 0){ free(b); goto emalloc; } pic->minx = lowx; pic->miny = lowy; pic->maxx = higx; pic->maxy = higy; pic->data = b; strcpy(pic->name, bp->rgn); return pic; }