internal_t*i = (internal_t*)dev->internal;
ArtSVP* svp = gfxfillToSVP(line, 1);
+ if (svp->n_segs > 500)
+ {
+ int lineParts = 0;
+ gfxline_t* lineCursor = line;
+ while(lineCursor != NULL)
+ {
+ if(lineCursor->type != gfx_moveTo) ++lineParts;
+ lineCursor = lineCursor->next;
+ }
+ fprintf(stderr, "arts_fill abandonning shape with %d segments (%d line parts)\n", svp->n_segs, lineParts);
+ art_svp_free(svp);
+ return;
+ }
+
svp = art_svp_rewind_uncrossed(art_svp_uncross(svp),ART_WIND_RULE_ODDEVEN); /*FIXME*/
if(i->clip) {
dbg("arts_fillbitmap");
internal_t*i = (internal_t*)dev->internal;
ArtSVP* svp = gfxfillToSVP(line, 1);
+
+ // We need to make sure that the SVP we now have bounds an area (i.e. the
+ // source line wound anticlockwise) rather than excludes an area (i.e. the
+ // line wound clockwise). It seems that PDF (or xpdf) is less strict about
+ // this for bitmaps than it is for fill areas.
+ //
+ // To check this, we'll sum the cross products of all pairs of adjacent
+ // lines. If the result is positive, the direction is correct; if not, we
+ // need to reverse the sense of the SVP generated. The easiest way to do
+ // this is to flip the up/down flags of all the segments.
+ //
+ // This is approximate; since the gfxline_t structure can contain any
+ // combination of moveTo, lineTo and splineTo in any order, not all pairs
+ // of lines in the shape that share a point need be described next to each
+ // other in the sequence. For ease, we'll consider only pairs of lines
+ // stored as lineTos and splineTos without intervening moveTos.
+ //
+ // TODO is this a valid algorithm? My vector maths is rusty.
+ //
+ // It may be more correct to instead reverse the line before we feed it
+ // into gfxfilltoSVP. However, this seems equivalent and is easier to
+ // implement!
+ double total_cross_product = 0.0;
+ gfxline_t* cursor = line;
+ if (cursor != NULL)
+ {
+ double x_last = cursor->x;
+ double y_last = cursor->y;
+ cursor = cursor->next;
+
+ while((cursor != NULL) && (cursor->next != NULL))
+ {
+ if (((cursor->type == gfx_lineTo) || (cursor->type == gfx_splineTo))
+ && ((cursor->next->type == gfx_lineTo) || (cursor->next->type == gfx_splineTo)))
+ {
+ // Process these lines
+ //
+ // In this space (x right, y down) the cross-product is
+ // (x1 * y0) - (x0 * y1)
+ double x0 = cursor->x - x_last;
+ double y0 = cursor->y - y_last;
+ double x1 = cursor->next->x - cursor->x;
+ double y1 = cursor->next->y - cursor->y;
+ total_cross_product += (x1 * y0) - (x0 * y1);
+ }
+
+ x_last = cursor->x;
+ y_last = cursor->y;
+ cursor = cursor->next;
+ }
+ }
+ if (total_cross_product < 0.0)
+ {
+ int i = 0;
+ for(; i < svp->n_segs; ++i)
+ {
+ if (svp->segs[i].dir != 0)
+ svp->segs[i].dir = 0;
+ else
+ svp->segs[i].dir = 1;
+ }
+ }
+
if(i->clip) {
ArtSVP*old = svp;
svp = art_svp_intersect(svp, i->clip->svp);