4 static ArtVpath* gfxline_to_ArtVpath(gfxline_t*line)
11 /* factor which determines into how many line fragments a spline is converted */
12 double subfraction = 2.4;//0.3
16 if(l2->type == gfx_moveTo) {
18 } if(l2->type == gfx_lineTo) {
20 } if(l2->type == gfx_splineTo) {
21 int parts = (int)(sqrt(fabs(l2->x-2*l2->sx+x) + fabs(l2->y-2*l2->sy+y))*subfraction);
32 vec = art_new (ArtVpath, len+1);
37 if(l2->type == gfx_moveTo) {
38 vec[pos].code = ART_MOVETO;
43 } else if(l2->type == gfx_lineTo) {
44 vec[pos].code = ART_LINETO;
49 } else if(l2->type == gfx_splineTo) {
51 int parts = (int)(sqrt(fabs(l2->x-2*l2->sx+x) + fabs(l2->y-2*l2->sy+y))*subfraction);
52 double stepsize = parts?1.0/parts:0;
53 for(i=0;i<=parts;i++) {
54 double t = (double)i*stepsize;
55 vec[pos].code = ART_LINETO;
56 vec[pos].x = l2->x*t*t + 2*l2->sx*t*(1-t) + x*(1-t)*(1-t);
57 vec[pos].y = l2->y*t*t + 2*l2->sy*t*(1-t) + y*(1-t)*(1-t);
66 vec[pos].code = ART_END;
68 /* fix "dotted" lines */
71 for(t=0;vec[t].code!=ART_END;t++) {
72 if(t>0 && vec[t-1].code==ART_MOVETO && vec[t].code==ART_LINETO
73 && vec[t+1].code!=ART_LINETO
74 && vec[t-1].x == vec[t].x
75 && vec[t-1].y == vec[t].y) {
78 if(vec[t].code==ART_MOVETO)
84 // Spot adjacent identical points
88 if ((vec[t-1].x == vec[t].x) && (vec[t-1].y == vec[t].y)) {
89 // adjacent identical points; remove one
90 memcpy(&(vec[t]), &(vec[t + 1]), sizeof(vec[t]) * (pos - t));
97 /* adjacency remover disabled for now, pending code inspection */
100 // Check for further non-adjacent identical points. We don't want any
101 // points other than the first and last points to exactly match.
103 // If we do find matching points, move the second point slightly. This
104 // currently moves the duplicate 2% towards the midpoint of its neighbours
105 // (easier to calculate than 2% down the perpendicular to the line joining
106 // the neighbours) but limiting the change to 0.1 twips to avoid visual
107 // problems when the shapes are large. Note that there is no minimum
108 // change: if the neighbouring points are colinear and equally spaced,
109 // e.g. they were generated as part of a straight spline, then the
110 // duplicate point may not actually move.
112 // The scan for duplicates algorithm is quadratic in the number of points:
113 // there's probably a better method but the numbers of points is generally
114 // small so this will do for now.
117 for(; i < (pos - 1); ++i)
119 for (j = 0; j < i; ++j)
121 if ((vec[i].x == vec[j].x)
122 && (vec[i].y == vec[j].y))
124 // points match; shuffle point
125 double dx = (vec[i-1].x + vec[i+1].x - (vec[i].x * 2.0)) / 100.0;
126 double dy = (vec[i-1].y + vec[i+1].y - (vec[i].y * 2.0)) / 100.0;
127 double dxxyy = (dx*dx) + (dy*dy);
130 // This is more than 0.1 twip's distance; scale down
131 double dscale = sqrt(dxxyy) * 10.0;
146 static void show_path(ArtSVP*path)
149 printf("Segments: %d\n", path->n_segs);
150 for(t=0;t<path->n_segs;t++) {
151 ArtSVPSeg* seg = &path->segs[t];
152 printf("Segment %d: %d points, %s, BBox: (%f,%f,%f,%f)\n",
153 t, seg->n_points, seg->dir==0?"UP ":"DOWN",
154 seg->bbox.x0, seg->bbox.y0, seg->bbox.x1, seg->bbox.y1);
156 for(p=0;p<seg->n_points;p++) {
157 ArtPoint* point = &seg->points[p];
158 printf(" (%f,%f)\n", point->x, point->y);
164 static ArtSVP* gfxfillToSVP(gfxline_t*line, int perturb)
166 ArtVpath* vec = gfxline_to_ArtVpath(line);
168 ArtVpath* vec2 = art_vpath_perturb(vec);
172 ArtSVP *svp = art_svp_from_vpath(vec);
175 // We need to make sure that the SVP we now have bounds an area (i.e. the
176 // source line wound anticlockwise) rather than excludes an area (i.e. the
177 // line wound clockwise). It seems that PDF (or xpdf) is less strict about
178 // this for bitmaps than it is for fill areas.
180 // To check this, we'll sum the cross products of all pairs of adjacent
181 // lines. If the result is positive, the direction is correct; if not, we
182 // need to reverse the sense of the SVP generated. The easiest way to do
183 // this is to flip the up/down flags of all the segments.
185 // This is approximate; since the gfxline_t structure can contain any
186 // combination of moveTo, lineTo and splineTo in any order, not all pairs
187 // of lines in the shape that share a point need be described next to each
188 // other in the sequence. For ease, we'll consider only pairs of lines
189 // stored as lineTos and splineTos without intervening moveTos.
191 // TODO is this a valid algorithm? My vector maths is rusty.
193 // It may be more correct to instead reverse the line before we feed it
194 // into gfxfilltoSVP. However, this seems equivalent and is easier to
196 double total_cross_product = 0.0;
197 gfxline_t* cursor = line;
200 double x_last = cursor->x;
201 double y_last = cursor->y;
202 cursor = cursor->next;
204 while((cursor != NULL) && (cursor->next != NULL))
206 if (((cursor->type == gfx_lineTo) || (cursor->type == gfx_splineTo))
207 && ((cursor->next->type == gfx_lineTo) || (cursor->next->type == gfx_splineTo)))
209 // Process these lines
211 // In this space (x right, y down) the cross-product is
212 // (x1 * y0) - (x0 * y1)
213 double x0 = cursor->x - x_last;
214 double y0 = cursor->y - y_last;
215 double x1 = cursor->next->x - cursor->x;
216 double y1 = cursor->next->y - cursor->y;
217 total_cross_product += (x1 * y0) - (x0 * y1);
222 cursor = cursor->next;
225 if (total_cross_product < 0.0)
228 for(; i < svp->n_segs; ++i)
230 if (svp->segs[i].dir != 0)
231 svp->segs[i].dir = 0;
233 svp->segs[i].dir = 1;
238 static ArtSVP* boxToSVP(double x1, double y1,double x2, double y2)
240 ArtVpath *vec = art_new (ArtVpath, 5+1);
241 vec[0].code = ART_MOVETO;
244 vec[1].code = ART_LINETO;
247 vec[2].code = ART_LINETO;
250 vec[3].code = ART_LINETO;
253 vec[4].code = ART_LINETO;
256 vec[5].code = ART_END;
259 ArtSVP *svp = art_svp_from_vpath(vec);
264 static ArtSVP* gfxstrokeToSVP(gfxline_t*line, gfxcoord_t width, gfx_capType cap_style, gfx_joinType joint_style, double miterLimit)
266 ArtVpath* vec = gfxline_to_ArtVpath(line);
268 ArtSVP *svp = art_svp_vpath_stroke (vec,
269 (joint_style==gfx_joinMiter)?ART_PATH_STROKE_JOIN_MITER:
270 ((joint_style==gfx_joinRound)?ART_PATH_STROKE_JOIN_ROUND:
271 ((joint_style==gfx_joinBevel)?ART_PATH_STROKE_JOIN_BEVEL:ART_PATH_STROKE_JOIN_BEVEL)),
272 (cap_style==gfx_capButt)?ART_PATH_STROKE_CAP_BUTT:
273 ((cap_style==gfx_capRound)?ART_PATH_STROKE_CAP_ROUND:
274 ((cap_style==gfx_capSquare)?ART_PATH_STROKE_CAP_SQUARE:ART_PATH_STROKE_CAP_SQUARE)),
276 miterLimit, //miter_limit
283 static gfxline_t* SVPtogfxline(ArtSVP*svp)
288 for(t=0;t<svp->n_segs;t++) {
289 size += svp->segs[t].n_points + 1;
291 gfxline_t* lines = (gfxline_t*)rfx_alloc(sizeof(gfxline_t)*size);
293 for(t=0;t<svp->n_segs;t++) {
294 ArtSVPSeg* seg = &svp->segs[t];
296 for(p=0;p<seg->n_points;p++) {
297 lines[pos].type = p==0?gfx_moveTo:gfx_lineTo;
298 ArtPoint* point = &seg->points[p];
299 lines[pos].x = point->x;
300 lines[pos].y = point->y;
301 lines[pos].next = &lines[pos+1];
306 lines[pos-1].next = 0;