cairo_int_status_t
_cairo_path_fixed_fill_rectilinear_to_traps (const cairo_path_fixed_t *path,
cairo_fill_rule_t fill_rule,
cairo_traps_t *traps)
{
cairo_box_t box;
cairo_status_t status;
traps->is_rectilinear = TRUE;
traps->is_rectangular = TRUE;
if (_cairo_path_fixed_is_box (path, &box)) {
return _cairo_traps_tessellate_rectangle (traps, &box.p1, &box.p2);
} else {
cairo_path_fixed_iter_t iter;
_cairo_path_fixed_iter_init (&iter, path);
while (_cairo_path_fixed_iter_is_fill_box (&iter, &box)) {
if (box.p1.y > box.p2.y) {
cairo_fixed_t t;
t = box.p1.y;
box.p1.y = box.p2.y;
box.p2.y = t;
t = box.p1.x;
box.p1.x = box.p2.x;
box.p2.x = t;
}
status = _cairo_traps_tessellate_rectangle (traps,
&box.p1, &box.p2);
if (unlikely (status)) {
_cairo_traps_clear (traps);
return status;
}
}
if (_cairo_path_fixed_iter_at_end (&iter))
return _cairo_bentley_ottmann_tessellate_rectangular_traps (traps, fill_rule);
_cairo_traps_clear (traps);
return CAIRO_INT_STATUS_UNSUPPORTED;
}
}
cairo_status_t
_cairo_bentley_ottmann_tessellate_rectangular_traps (cairo_traps_t *traps,
cairo_fill_rule_t fill_rule)
{
rectangle_t stack_rectangles[CAIRO_STACK_ARRAY_LENGTH (rectangle_t)];
rectangle_t *stack_rectangles_ptrs[ARRAY_LENGTH (stack_rectangles) + 3];
rectangle_t *rectangles, **rectangles_ptrs;
cairo_status_t status;
int i;
assert (traps->is_rectangular);
if (unlikely (traps->num_traps <= 1)) {
if (traps->num_traps == 1) {
cairo_trapezoid_t *trap = traps->traps;
if (trap->left.p1.x > trap->right.p1.x) {
cairo_line_t tmp = trap->left;
trap->left = trap->right;
trap->right = tmp;
}
}
return CAIRO_STATUS_SUCCESS;
}
dump_traps (traps, "bo-rects-traps-in.txt");
rectangles = stack_rectangles;
rectangles_ptrs = stack_rectangles_ptrs;
if (traps->num_traps > ARRAY_LENGTH (stack_rectangles)) {
rectangles = _cairo_malloc_ab_plus_c (traps->num_traps,
sizeof (rectangle_t) +
sizeof (rectangle_t *),
3*sizeof (rectangle_t *));
if (unlikely (rectangles == NULL))
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
rectangles_ptrs = (rectangle_t **) (rectangles + traps->num_traps);
}
for (i = 0; i < traps->num_traps; i++) {
if (traps->traps[i].left.p1.x < traps->traps[i].right.p1.x) {
rectangles[i].left.x = traps->traps[i].left.p1.x;
rectangles[i].left.dir = 1;
rectangles[i].right.x = traps->traps[i].right.p1.x;
rectangles[i].right.dir = -1;
} else {
rectangles[i].right.x = traps->traps[i].left.p1.x;
rectangles[i].right.dir = 1;
rectangles[i].left.x = traps->traps[i].right.p1.x;
rectangles[i].left.dir = -1;
}
rectangles[i].left.right = NULL;
rectangles[i].right.right = NULL;
rectangles[i].top = traps->traps[i].top;
rectangles[i].bottom = traps->traps[i].bottom;
rectangles_ptrs[i+2] = &rectangles[i];
}
/* XXX incremental sort */
_rectangle_sort (rectangles_ptrs+2, i);
_cairo_traps_clear (traps);
status = _cairo_bentley_ottmann_tessellate_rectangular (rectangles_ptrs+2, i,
fill_rule,
TRUE, traps);
traps->is_rectilinear = TRUE;
traps->is_rectangular = TRUE;
if (rectangles != stack_rectangles)
free (rectangles);
dump_traps (traps, "bo-rects-traps-out.txt");
return status;
}
static cairo_int_status_t
_cairo_path_fixed_stroke_rectilinear (cairo_path_fixed_t *path,
cairo_stroke_style_t *stroke_style,
const cairo_matrix_t *ctm,
cairo_traps_t *traps)
{
cairo_rectilinear_stroker_t rectilinear_stroker;
cairo_int_status_t status;
/* This special-case rectilinear stroker only supports
* miter-joined lines (not curves) and a translation-only matrix
* (though it could probably be extended to support a matrix with
* uniform, integer scaling).
*
* It also only supports horizontal and vertical line_to
* elements. But we don't catch that here, but instead return
* UNSUPPORTED from _cairo_rectilinear_stroker_line_to if any
* non-rectilinear line_to is encountered.
*/
if (path->has_curve_to)
return CAIRO_INT_STATUS_UNSUPPORTED;
if (stroke_style->line_join != CAIRO_LINE_JOIN_MITER)
return CAIRO_INT_STATUS_UNSUPPORTED;
/* If the miter limit turns right angles into bevels, then we
* can't use this optimization. Remember, the ratio is
* 1/sin(ɸ/2). So the cutoff is 1/sin(π/4.0) or ⎷2,
* which we round for safety. */
if (stroke_style->miter_limit < M_SQRT2)
return CAIRO_INT_STATUS_UNSUPPORTED;
if (! (stroke_style->line_cap == CAIRO_LINE_CAP_BUTT ||
stroke_style->line_cap == CAIRO_LINE_CAP_SQUARE))
{
return CAIRO_INT_STATUS_UNSUPPORTED;
}
if (! (_cairo_matrix_is_identity (ctm) ||
_cairo_matrix_is_translation (ctm)))
{
return CAIRO_INT_STATUS_UNSUPPORTED;
}
_cairo_rectilinear_stroker_init (&rectilinear_stroker,
stroke_style,
ctm,
traps);
if (traps->has_limits) {
_cairo_rectilinear_stroker_limit (&rectilinear_stroker,
&traps->limits);
}
status = _cairo_path_fixed_interpret (path,
CAIRO_DIRECTION_FORWARD,
_cairo_rectilinear_stroker_move_to,
rectilinear_stroker.dash.dashed ?
_cairo_rectilinear_stroker_line_to_dashed :
_cairo_rectilinear_stroker_line_to,
NULL,
_cairo_rectilinear_stroker_close_path,
&rectilinear_stroker);
if (unlikely (status))
goto BAIL;
if (rectilinear_stroker.dash.dashed)
status = _cairo_rectilinear_stroker_emit_segments_dashed (&rectilinear_stroker);
else
status = _cairo_rectilinear_stroker_emit_segments (&rectilinear_stroker);
BAIL:
_cairo_rectilinear_stroker_fini (&rectilinear_stroker);
if (unlikely (status))
_cairo_traps_clear (traps);
return status;
}
cairo_status_t
_cairo_bentley_ottmann_tessellate_rectilinear_traps (cairo_traps_t *traps,
cairo_fill_rule_t fill_rule)
{
cairo_bo_event_t stack_events[CAIRO_STACK_ARRAY_LENGTH (cairo_bo_event_t)];
cairo_bo_event_t *events;
cairo_bo_event_t *stack_event_ptrs[ARRAY_LENGTH (stack_events) + 1];
cairo_bo_event_t **event_ptrs;
cairo_bo_edge_t stack_edges[ARRAY_LENGTH (stack_events)];
cairo_bo_edge_t *edges;
cairo_status_t status;
int i, j, k;
if (unlikely (traps->num_traps == 0))
return CAIRO_STATUS_SUCCESS;
assert (traps->is_rectilinear);
i = 4 * traps->num_traps;
events = stack_events;
event_ptrs = stack_event_ptrs;
edges = stack_edges;
if (i > ARRAY_LENGTH (stack_events)) {
events = _cairo_malloc_ab_plus_c (i,
sizeof (cairo_bo_event_t) +
sizeof (cairo_bo_edge_t) +
sizeof (cairo_bo_event_t *),
sizeof (cairo_bo_event_t *));
if (unlikely (events == NULL))
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
event_ptrs = (cairo_bo_event_t **) (events + i);
edges = (cairo_bo_edge_t *) (event_ptrs + i + 1);
}
for (i = j = k = 0; i < traps->num_traps; i++) {
edges[k].edge.top = traps->traps[i].top;
edges[k].edge.bottom = traps->traps[i].bottom;
edges[k].edge.line = traps->traps[i].left;
edges[k].edge.dir = 1;
edges[k].deferred_trap.right = NULL;
edges[k].prev = NULL;
edges[k].next = NULL;
event_ptrs[j] = &events[j];
events[j].type = CAIRO_BO_EVENT_TYPE_START;
events[j].point.y = traps->traps[i].top;
events[j].point.x = traps->traps[i].left.p1.x;
events[j].edge = &edges[k];
j++;
event_ptrs[j] = &events[j];
events[j].type = CAIRO_BO_EVENT_TYPE_STOP;
events[j].point.y = traps->traps[i].bottom;
events[j].point.x = traps->traps[i].left.p1.x;
events[j].edge = &edges[k];
j++;
k++;
edges[k].edge.top = traps->traps[i].top;
edges[k].edge.bottom = traps->traps[i].bottom;
edges[k].edge.line = traps->traps[i].right;
edges[k].edge.dir = -1;
edges[k].deferred_trap.right = NULL;
edges[k].prev = NULL;
edges[k].next = NULL;
event_ptrs[j] = &events[j];
events[j].type = CAIRO_BO_EVENT_TYPE_START;
events[j].point.y = traps->traps[i].top;
events[j].point.x = traps->traps[i].right.p1.x;
events[j].edge = &edges[k];
j++;
event_ptrs[j] = &events[j];
events[j].type = CAIRO_BO_EVENT_TYPE_STOP;
events[j].point.y = traps->traps[i].bottom;
events[j].point.x = traps->traps[i].right.p1.x;
events[j].edge = &edges[k];
j++;
k++;
}
_cairo_traps_clear (traps);
status = _cairo_bentley_ottmann_tessellate_rectilinear (event_ptrs, j,
fill_rule,
TRUE, traps);
traps->is_rectilinear = TRUE;
if (events != stack_events)
free (events);
return status;
}
static cairo_int_status_t
_cairo_clip_path_to_region_geometric (cairo_clip_path_t *clip_path)
{
cairo_traps_t traps;
cairo_box_t stack_boxes[CAIRO_STACK_ARRAY_LENGTH (cairo_box_t)];
cairo_box_t *boxes = stack_boxes;
cairo_status_t status;
int n;
/* If we have nothing to intersect with this path, then it cannot
* magically be reduced into a region.
*/
if (clip_path->prev == NULL)
goto UNSUPPORTED;
/* Start simple... Intersect some boxes with an arbitrary path. */
if (! clip_path->path.is_rectilinear)
goto UNSUPPORTED;
if (clip_path->prev->prev != NULL)
goto UNSUPPORTED;
_cairo_traps_init (&traps);
_cairo_box_from_rectangle (&boxes[0], &clip_path->extents);
_cairo_traps_limit (&traps, boxes, 1);
status = _cairo_path_fixed_fill_rectilinear_to_traps (&clip_path->path,
clip_path->fill_rule,
&traps);
if (unlikely (_cairo_status_is_error (status)))
return status;
if (status == CAIRO_INT_STATUS_UNSUPPORTED)
goto UNSUPPORTED;
if (traps.num_traps > ARRAY_LENGTH (stack_boxes)) {
boxes = _cairo_malloc_ab (traps.num_traps, sizeof (cairo_box_t));
if (unlikely (boxes == NULL))
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
}
for (n = 0; n < traps.num_traps; n++) {
boxes[n].p1.x = traps.traps[n].left.p1.x;
boxes[n].p1.y = traps.traps[n].top;
boxes[n].p2.x = traps.traps[n].right.p1.x;
boxes[n].p2.y = traps.traps[n].bottom;
}
_cairo_traps_clear (&traps);
_cairo_traps_limit (&traps, boxes, n);
status = _cairo_path_fixed_fill_to_traps (&clip_path->prev->path,
clip_path->prev->fill_rule,
clip_path->prev->tolerance,
&traps);
if (boxes != stack_boxes)
free (boxes);
if (unlikely (status))
return status;
status = _cairo_traps_extract_region (&traps, &clip_path->region);
_cairo_traps_fini (&traps);
if (status == CAIRO_INT_STATUS_UNSUPPORTED)
goto UNSUPPORTED;
if (unlikely (status))
return status;
clip_path->flags |= CAIRO_CLIP_PATH_HAS_REGION;
return CAIRO_STATUS_SUCCESS;
UNSUPPORTED:
clip_path->flags |= CAIRO_CLIP_PATH_REGION_IS_UNSUPPORTED;
return CAIRO_INT_STATUS_UNSUPPORTED;
}
