// convert a rectagle and return bounding box of resulting figure
dRect
Conv::bb_frw(const dRect & R, double acc, int max) const {
dLine l = line_frw(rect2line(R), acc, max);
return l.range();
}
int
GObjGridPulk::draw(iImage & image, const iPoint & origin){
/* find wgs coordinate range and 6 degree zones */
const g_map m = *get_ref();
dPoint dorg(origin);
dRect rng = image.range() + dorg;
dRect rng_wgs = cnv.bb_frw(rng); // screen -> wgs
int lon0a = convs::lon2lon0(rng_wgs.TLC().x);
int lon0b = convs::lon2lon0(rng_wgs.BRC().x);
/* for all zones */
for (int lon0=lon0a; lon0<=lon0b; lon0+=6){
/* build screen -> pulkovo conversion or get it from the cache */
if (!convs.contains(lon0)){
Options o;
o.put("lon0", lon0);
convs.add(lon0, convs::map2pt(m, Datum("pulk"), Proj("tmerc"), o));
}
convs::map2pt cnv1(convs.get(lon0));
dRect rng_pulk = cnv1.bb_frw(rng); // screen -> pulkovo
if (std::isinf(rng_pulk.w) || std::isinf(rng_pulk.w)) continue;
double step = 1000;
while (rng_pulk.w> step*10 || rng_pulk.h> step*10) step*=10.0;
while (rng_pulk.w< step/10 || rng_pulk.h< step/10) step/=10.0;
dPoint tlc = rng_pulk.TLC(), brc= rng_pulk.BRC();
double xmin = floor(tlc.x/step)*step;
double xmax = ceil(brc.x/step)*step;
double ymin = floor(tlc.y/step)*step;
double ymax = ceil(brc.y/step)*step;
CairoWrapper cr(image);
cr->set_source_rgba(1,0,0,1);
cr->set_line_width(2);
if (lon0a!=lon0b){ /* clip the zone */
dRect rng_clip(lon0-3.0, rng_wgs.y, 6.0, rng_wgs.h);
rng_wgs.y-=rng_wgs.h*0.2;
rng_wgs.h+=rng_wgs.h*0.4;
cr->mkpath(cnv.line_bck(rect2line(rng_clip,1)) - dorg);
cr->clip_preserve();
cr->stroke();
}
for (double x=xmin; x<=xmax; x+=step){
dPoint p1(x, tlc.y), p2(x, brc.y);
cnv1.bck(p1), cnv1.bck(p2);
cr->move_to(p1-dorg);
cr->line_to(p2-dorg);
}
for (double y=ymin; y<=ymax; y+=step){
dPoint p1(tlc.x, y), p2(brc.x, y);
cnv1.bck(p1), cnv1.bck(p2);
cr->move_to(p1-dorg);
cr->line_to(p2-dorg);
}
cr->stroke();
/* step for labels */
step*=2;
xmin = floor(tlc.x/step)*step;
xmax = ceil(brc.x/step)*step;
ymin = floor(tlc.y/step)*step;
ymax = ceil(brc.y/step)*step;
/* labels */
cr->set_fig_font(18, 15, 100);
for (double x=xmin; x<=xmax; x+=step){
for (double y=ymin; y<=ymax; y+=step){
stringstream sx, sy;
sx << int(x/1000), sy << int(y/1000);
dPoint p1(x,y); cnv1.bck(p1);
cr->move_to(p1-dorg + dPoint(5, -5));
cr->show_text(sy.str());
cr->move_to(p1-dorg + dPoint(20, -25));
cr->save();
cr->rotate(-M_PI/2.0);
cr->show_text(sx.str());
cr->restore();
}
}
}
return GObj::FILL_PART;
}
