/*------------------------------------------------------------------------------
Id numbers of polygons containing az, el positions.
The az, el positions are read from in_filename,
and the results are written to out_filename.
Implemented as interpretive read/write, to permit interactive behaviour.
Input: in_filename = name of file to read from;
"" or "-" means read from standard input.
out_filename = name of file to write to;
"" or "-" means write to standard output.
fmt = pointer to format structure.
poly = array of pointers to polygons.
npoly = number of polygons in poly array.
Return value: number of lines written,
or -1 if error occurred.
*/
int poly_ids(char *in_filename, char *out_filename, format *fmt, int npoly, polygon *poly[/*npoly*/])
{
#define AZEL_STR_LEN 32
char input[] = "input", output[] = "output";
char *word, *next;
char az_str[AZEL_STR_LEN], el_str[AZEL_STR_LEN];
int i, idwidth, ird, len, nid, nids, nid0, nid2, np;
long long idmin, idmax;
long long *id;
long double *weight;
azel v;
char *out_fn;
FILE *outfile;
int *start;
int *total;
int *parent_pixels;
int p, res, max_pixel, ier, sorted;
ier=-1;
sorted=0;
while(ier!=0){
max_pixel= poly[npoly-1]->pixel;
res_max=get_res(max_pixel, scheme);
max_pixel=pixel_start(res_max+1,scheme);
/* allocate memory for pixel info arrays start and total */
msg("res_max=%d, max_pixel=%d\n",res_max,max_pixel);
start = (int *) malloc(sizeof(int) * max_pixel);
if (!start) {
fprintf(stderr, "polyid: failed to allocate memory for %d integers\n", max_pixel);
return(-1);
}
total = (int *) malloc(sizeof(int) * max_pixel);
if (!total) {
fprintf(stderr, "polyid: failed to allocate memory for %d integers\n", max_pixel);
return(-1);
}
parent_pixels = (int *) malloc(sizeof(int) * (res_max+1));
if (!parent_pixels) {
fprintf(stderr, "polyid: failed to allocate memory for %d integers\n", res_max+1);
return(-1);
}
/* build lists of starting indices of each pixel and total number of polygons in each pixel*/
ier=pixel_list(npoly, poly, max_pixel, start, total);
if (ier == -1) {
// if pixel_list returns an error, try sorting the polygons and trying again
if(!sorted){
msg("sorting polygons...\n");
poly_sort(npoly,poly,'p');
sorted=1;
}
else{
fprintf(stderr, "poly_ids: error building pixel index lists\n");
return(-1);
}
}
}
/* open in_filename for reading */
if (!in_filename || strcmp(in_filename, "-") == 0) {
file.file = stdin;
file.name = input;
} else {
file.file = fopen(in_filename, "r");
if (!file.file) {
fprintf(stderr, "cannot open %s for reading\n", in_filename);
return(-1);
}
file.name = in_filename;
}
file.line_number = 0;
/* open out_filename for writing */
if (!out_filename || strcmp(out_filename, "-") == 0) {
outfile = stdout;
out_fn = output;
} else {
outfile = fopen(out_filename, "w");
if (!outfile) {
fprintf(stderr, "cannot open %s for writing\n", out_filename);
return(-1);
}
out_fn = out_filename;
}
/* advise angular units */
msg("will take units of input az, el angles in %s to be ", file.name);
switch (fmt->inunit) {
#include "angunit.h"
}
msg("\n");
if (fmt->outunit != fmt->inunit) {
msg("units of output az, el angles will be ");
switch (fmt->outunit) {
#include "angunit.h"
}
msg("\n");
}
/* largest width of polygon id number */
idmin = 0;
idmax = 0;
for (i = 0; i < npoly; i++) {
if (!poly[i]) continue;
if (poly[i]->id < idmin) idmin = poly[i]->id;
if (poly[i]->id > idmax) idmax = poly[i]->id;
}
idmin = ((idmin < 0)? floorl(log10l((long double)-idmin)) + 2 : 1);
idmax = ((idmax > 0)? floorl(log10l((long double)idmax)) + 1 : 1);
idwidth = ((idmin > idmax)? idmin : idmax);
/* write header */
v.az = 0.;
wrangle(v.az, fmt->outunit, fmt->outprecision, AZEL_STR_LEN, az_str);
len = strlen(az_str);
if (fmt->outunit == 'h') {
sprintf(az_str, "az(hms)");
sprintf(el_str, "el(dms)");
} else {
sprintf(az_str, "az(%c)", fmt->outunit);
sprintf(el_str, "el(%c)", fmt->outunit);
}
fprintf(outfile, "%*s %*s", len, az_str, len, el_str);
if (npoly > 0){
if(polyid_weight==1){
fprintf(outfile, " polygon_weights");
}
else{
fprintf(outfile, " polygon_ids");
}
}
fprintf(outfile, "\n");
/* interpretive read/write loop */
np = 0;
nid = 0;
nids = 0;
nid0 = 0;
nid2 = 0;
while (1) {
/* read line */
ird = rdline(&file);
/* serious error */
if (ird == -1) return(-1);
/* EOF */
if (ird == 0) break;
/* read <az> */
word = file.line;
ird = rdangle(word, &next, fmt->inunit, &v.az);
/* skip header */
if (ird != 1 && np == 0) continue;
/* otherwise exit on unrecognized characters */
if (ird != 1) break;
/* read <el> */
word = next;
ird = rdangle(word, &next, fmt->inunit, &v.el);
/* skip header */
if (ird != 1 && np == 0) continue;
/* otherwise exit on unrecognized characters */
if (ird != 1) break;
/* convert az and el from input units to radians */
scale_azel(&v, fmt->inunit, 'r');
//find out what pixel the az el point is in at the maximum resolution
p=which_pixel(v.az, v.el, res_max, scheme);
//get the list of all the possible parent pixels
get_parent_pixels(p, parent_pixels, scheme);
nid=0;
for(res=res_max;res>=0;res--){
p=parent_pixels[res];
//if this pixel isn't in the polygon list, go to next parent pixel
if(total[p]==0) continue;
// id numbers of the polygons containing position az, el
nid = poly_id(total[p], &poly[start[p]], v.az, v.el, &id, &weight);
}
/* convert az and el from radians to output units */
scale_azel(&v, 'r', fmt->outunit);
/* write result */
wrangle(v.az, fmt->outunit, fmt->outprecision, AZEL_STR_LEN, az_str);
wrangle(v.el, fmt->outunit, fmt->outprecision, AZEL_STR_LEN, el_str);
fprintf(outfile, "%s %s", az_str, el_str);
for (i = 0; i < nid; i++) {
if(polyid_weight==1){
fprintf(outfile, " %.18Lg", weight[i]);
} else{
fprintf(outfile, " %*lld", idwidth, id[i]);
}
}
fprintf(outfile, "\n");
fflush(outfile);
/* increment counters of results */
np++;
nids += nid;
if (nid == 0) {
nid0++;
} else if (nid >= 2) {
nid2++;
}
}
/* advise */
if (nid0 > 0) msg("%d points were not inside any polygon\n", nid0);
if (nid2 > 0) msg("%d points were inside >= 2 polygons\n", nid2);
if (outfile != stdout) {
if(polyid_weight==1){
msg("polyid: %d weights at %d positions written to %s\n", nids, np, out_fn);
} else {
msg("polyid: %d id numbers at %d positions written to %s\n", nids, np, out_fn);
}
}
free(start);
free(total);
free(parent_pixels);
return(np);
}
int which_pixel(double az, double el, int res, char scheme)
{
int n,m,pix,base_pix,i;
unsigned long pixnum;
double az_check, el_check;
int *parent_pixels;
if(az<0){
az+=TWOPI;
}
if(az>TWOPI || az<0){
fprintf(stderr, "error in which_pixel: az must lie between 0 and 2*PI.\n");
return(-1);
}
if(el>PIBYTWO || el<-PIBYTWO){
fprintf(stderr, "error in which_pixel: el must lie between -PI/2 and PI/2.\n");
return(-1);
}
if(res<0){
fprintf(stderr, "error in which_pixel: resolution must be an integer >=0.\n");
return(-1);
}
if(scheme=='s'){
// this scheme divides up the sphere by rectangles in az and el, and is numbered
// such that the resolution is encoded in each pixel number. The whole sky is pixel 0,
// pixels 1, 2, 3, and 4 are each 1/4 of the sky (resolution 1), pixels 5-20 are each
// 1/16 of the sky (resolution 2), etc.
if(az==TWOPI) az=0;
n=(sin(el)==1) ? 0 : ceil((1-sin(el))/2*pow(2,res))-1;
m=floor(az/(TWOPI)*pow(2,res));
base_pix=pow(2,res)*n+m;
pix=pixel_start(res,scheme)+base_pix;
return(pix);
}
else if(scheme=='d'){
assign_parameters();
if(az==TWOPI) az=0;
/* ang2pix_radec takes az and el in degrees */
az *= (180.0/PI);
el *= (180.0/PI);
if(res==0){
return(0);
}
else if(res==1){
parent_pixels = (int *) malloc(sizeof(int) * (3));
if(!parent_pixels){
fprintf(stderr, "error in which_pixel: failed to allocate memory for 3 integers\n");
return(-1);
}
ang2pix_radec(1, az, el, &pixnum);
pix = (int)pixnum;
i = get_parent_pixels(pix+pixel_start(2,scheme), parent_pixels, scheme);
if(i==1){
fprintf(stderr, "error in which_pixel: get_parent_pixels failed\n");
return(-1);
}
return(parent_pixels[1]);
}
else{
ang2pix_radec((int)pow(2,res-2), az, el, &pixnum);
pix = (int)pixnum;
/* check
pix2ang_radec((int)pow(2,res-1), pixnum, &az_check, &el_check);
printf("pix2ang_radec(pixnum = %d) = %f, %f\n", (int)pixnum, az_check, el_check); */
return(pix+pixel_start(res, scheme));
}
}
else{
fprintf(stderr, "error in which_pixel: pixel scheme %c not recognized.\n", scheme);
return(-1);
}
}
/*------------------------------------------------------------------------------
Take pixelized polygons, find the average weight within each pixel, and return a set of polygons consisting of the pixels weighted with the average weight.
Input: poly = array of pointers to polygons.
npoly = pointer to number of polygons.
Output: polys = array of pointers to polygons;
Return value: number of polygons discarded by pixelmapping,
or -1 if error occurred.
*/
int pixelmap(int *npoly, polygon *poly[/**npoly*/])
{
int i, j, nadj, k, kstart,kend,numpix;
int *start;
int *total;
int *parent_pixels;
int begin, end, p,max_pixel,min_pixel, ier, verb,res1,res2;
long double tol,area, tot_area;
long double *av_weight;
long double *av_weight0;
poly_sort(*npoly,poly,'p');
min_pixel = poly[0]->pixel;
max_pixel = poly[*npoly-1]->pixel+1;
res1=get_res(min_pixel,scheme);
res2=get_res(max_pixel,scheme);
if(res1<res_max){
fprintf(stderr,"pixelmap: there are pixels in the mask with a lower resolution than the desired pixelmap resolution %d. The desired pixelmap resolution can be set with the -P option.\n",res_max);
fprintf(stderr,"Before using pixelmap, use pixelize with the -P0,r option to pixelize the entire mask to the desired resolution r.\n");
return(-1);
}
/* allocate memory for pixel info arrays start and total */
start = (int *) malloc(sizeof(int) * max_pixel);
if (!start) {
fprintf(stderr, "pixelmap: failed to allocate memory for %d integers\n", max_pixel);
return(-1);
}
total = (int *) malloc(sizeof(int) * max_pixel);
if (!total) {
fprintf(stderr, "pixelmap: failed to allocate memory for %d integers\n", max_pixel);
return(-1);
}
/* build lists of starting indices of each pixel and total number of polygons in each pixel*/
ier=pixel_list(*npoly, poly, max_pixel, start, total);
if (ier == -1) {
fprintf(stderr, "pixelmap: error building pixel index lists\n");
return(-1);
}
//allocate memory for parent pixels array
parent_pixels = (int *) malloc(sizeof(int) * (res2+1));
if (!parent_pixels) {
fprintf(stderr, "pixelmap: failed to allocate memory for %d integers\n", res2+1);
return(-1);
}
//kstart=number of first pixel at desired output resolution
//kend=number of last pixel at desired output resolution
if(res_max==-1){
kstart=pixel_start(res1,scheme);
kend=pixel_start(res2+1,scheme)-1;
}
else{
kstart=pixel_start(res_max,scheme);
kend=pixel_start(res_max+1,scheme)-1;
}
av_weight0= (long double *) malloc(sizeof(long double) * (kend-kstart+1) );
if (!av_weight0) {
fprintf(stderr, "pixelmap: failed to allocate memory for %d integers\n", kend-kstart+1 );
return(-1);
}
//make av_weight an array indexed by the pixel number
av_weight=av_weight0-kstart;
//set av_weight array to 0 initially
for(k=kstart;k<=kend;k++){
av_weight[k]=0;
}
nadj = 0;
verb=1;
/*find average weight of polygons within each pixel*/
for(p=min_pixel;p<max_pixel;p++){
begin=start[p];
end=start[p]+total[p];
ier=get_parent_pixels(p,parent_pixels,scheme);
if(ier) return(-1);
//set k to the pixel at the desired output resolution, or to the pixel number if using
//existing resolution
k=(res_max==-1) ? p : parent_pixels[res_max];
for (i = begin; i < end; i++) {
if (!poly[i]) continue;
tol=mtol;
ier = garea(poly[i], &tol, verb, &area);
if(ier==1 || ier == -1){
fprintf(stderr, "error %d in garea in polygon %d\n", ier, poly[i]->id);
continue;
}
av_weight[k]+=poly[i]->weight * area;
}
}
//replace polygons in input array with non-zero weight pixels
j=0;
for(k=kstart;k<=kend;k++){
if(av_weight[k]==0) continue;
free_poly(poly[j]);
poly[j]=get_pixel(k,scheme);
tol=mtol;
ier = garea(poly[j], &tol, verb, &tot_area);
if(ier==1 || ier == -1){
fprintf(stderr, "pixelmap: error in garea in pixel %d\n",p);
continue;
}
poly[j]->weight=av_weight[k]/tot_area;
j++;
if(j> *npoly ){
fprintf(stderr,"pixelmap: number of pixels with non-zero weight exceeds number of polygons.\n");
fprintf(stderr, "Try running unify on your mask to remove zero-weight polygons before using pixelmap.\n");
}
}
numpix=j;
for(j=numpix; j< *npoly; j++){
free_poly(poly[j]);
poly[j] = 0x0;
nadj++;
}
*npoly=numpix;
free(start);
free(total);
free(parent_pixels);
free(av_weight0);
/* assign new polygon id numbers */
if (fmt.newid == 'n') {
for (i = 0; i < *npoly; i++) {
poly[i]->id = i;
}
}
if (fmt.newid == 'p') {
for (i = 0; i < *npoly; i++) {
poly[i]->id = poly[i]->pixel;
}
}
/* advise */
msg("pixelmap: %d pixels in map\n", numpix);
return(nadj);
}
