static cairo_int_status_t
_clip_to_traps (cairo_clip_t *clip,
cairo_traps_t *traps)
{
cairo_int_status_t status;
cairo_polygon_t polygon;
cairo_antialias_t antialias;
cairo_fill_rule_t fill_rule;
_cairo_traps_init (traps);
if (clip->num_boxes == 1 && clip->path == NULL) {
cairo_boxes_t boxes;
_cairo_boxes_init_for_array (&boxes, clip->boxes, clip->num_boxes);
return _cairo_traps_init_boxes (traps, &boxes);
}
status = _cairo_clip_get_polygon (clip, &polygon, &fill_rule, &antialias);
if (unlikely (status))
return status;
/* We ignore the antialias mode of the clip here, since the user requested
* unantialiased rendering of their path and we expect that this stencil
* based rendering of the clip to be a reasonable approximation to
* the intersection between that clip and the path.
*
* In other words, what the user expects when they try to perform
* a geometric intersection between an unantialiased polygon and an
* antialiased polygon is open to interpretation. And we choose the fast
* option.
*/
_cairo_traps_init (traps);
status = _cairo_bentley_ottmann_tessellate_polygon (traps,
&polygon,
fill_rule);
_cairo_polygon_fini (&polygon);
return status;
}
cairo_clip_t *
_cairo_clip_intersect_boxes (cairo_clip_t *clip,
const cairo_boxes_t *boxes)
{
cairo_boxes_t clip_boxes;
cairo_box_t limits;
cairo_rectangle_int_t extents;
if (_cairo_clip_is_all_clipped (clip))
return clip;
if (boxes->num_boxes == 0)
return _cairo_clip_set_all_clipped (clip);
if (boxes->num_boxes == 1)
return _cairo_clip_intersect_box (clip, boxes->chunks.base);
if (clip == NULL)
clip = _cairo_clip_create ();
if (clip->num_boxes) {
_cairo_boxes_init_for_array (&clip_boxes, clip->boxes, clip->num_boxes);
if (unlikely (_cairo_boxes_intersect (&clip_boxes, boxes, &clip_boxes))) {
clip = _cairo_clip_set_all_clipped (clip);
goto out;
}
if (clip->boxes != &clip->embedded_box)
free (clip->boxes);
clip->boxes = NULL;
boxes = &clip_boxes;
}
if (boxes->num_boxes == 0) {
clip = _cairo_clip_set_all_clipped (clip);
goto out;
} else if (boxes->num_boxes == 1) {
clip->boxes = &clip->embedded_box;
clip->boxes[0] = boxes->chunks.base[0];
clip->num_boxes = 1;
} else {
clip->boxes = _cairo_boxes_to_array (boxes, &clip->num_boxes, TRUE);
}
_cairo_boxes_extents (boxes, &limits);
_cairo_box_round_to_rectangle (&limits, &extents);
if (clip->path == NULL)
clip->extents = extents;
else if (! _cairo_rectangle_intersect (&clip->extents, &extents))
clip = _cairo_clip_set_all_clipped (clip);
if (clip->region) {
cairo_region_destroy (clip->region);
clip->region = NULL;
}
clip->is_region = FALSE;
out:
if (boxes == &clip_boxes)
_cairo_boxes_fini (&clip_boxes);
return clip;
}
static cairo_surface_t *
get_clip_surface (const cairo_spans_compositor_t *compositor,
cairo_surface_t *dst,
const cairo_clip_t *clip,
const cairo_rectangle_int_t *extents)
{
cairo_composite_rectangles_t composite;
cairo_surface_t *surface;
cairo_box_t box;
cairo_polygon_t polygon;
const cairo_clip_path_t *clip_path;
cairo_antialias_t antialias;
cairo_fill_rule_t fill_rule;
cairo_int_status_t status;
assert (clip->path);
surface = _cairo_surface_create_similar_solid (dst,
CAIRO_CONTENT_ALPHA,
extents->width,
extents->height,
CAIRO_COLOR_TRANSPARENT);
_cairo_box_from_rectangle (&box, extents);
_cairo_polygon_init (&polygon, &box, 1);
clip_path = clip->path;
status = _cairo_path_fixed_fill_to_polygon (&clip_path->path,
clip_path->tolerance,
&polygon);
if (unlikely (status))
goto cleanup_polygon;
antialias = clip_path->antialias;
fill_rule = clip_path->fill_rule;
if (clip->boxes) {
cairo_polygon_t intersect;
cairo_boxes_t tmp;
_cairo_boxes_init_for_array (&tmp, clip->boxes, clip->num_boxes);
status= _cairo_polygon_init_boxes (&intersect, &tmp);
if (unlikely (status))
goto cleanup_polygon;
status = _cairo_polygon_intersect (&polygon, fill_rule,
&intersect, CAIRO_FILL_RULE_WINDING);
_cairo_polygon_fini (&intersect);
if (unlikely (status))
goto cleanup_polygon;
fill_rule = CAIRO_FILL_RULE_WINDING;
}
polygon.limits = NULL;
polygon.num_limits = 0;
clip_path = clip_path->prev;
while (clip_path) {
if (clip_path->antialias == antialias) {
cairo_polygon_t next;
_cairo_polygon_init (&next, NULL, 0);
status = _cairo_path_fixed_fill_to_polygon (&clip_path->path,
clip_path->tolerance,
&next);
if (likely (status == CAIRO_INT_STATUS_SUCCESS))
status = _cairo_polygon_intersect (&polygon, fill_rule,
&next, clip_path->fill_rule);
_cairo_polygon_fini (&next);
if (unlikely (status))
goto cleanup_polygon;
fill_rule = CAIRO_FILL_RULE_WINDING;
}
clip_path = clip_path->prev;
}
_cairo_polygon_translate (&polygon, -extents->x, -extents->y);
status = _cairo_composite_rectangles_init_for_polygon (&composite, surface,
CAIRO_OPERATOR_ADD,
&_cairo_pattern_white.base,
&polygon,
NULL);
if (unlikely (status))
goto cleanup_polygon;
status = composite_polygon (compositor, &composite,
&polygon, fill_rule, antialias);
_cairo_composite_rectangles_fini (&composite);
_cairo_polygon_fini (&polygon);
if (unlikely (status))
goto error;
_cairo_polygon_init (&polygon, &box, 1);
clip_path = clip->path;
antialias = clip_path->antialias == CAIRO_ANTIALIAS_DEFAULT ? CAIRO_ANTIALIAS_NONE : CAIRO_ANTIALIAS_DEFAULT;
clip_path = clip_path->prev;
while (clip_path) {
if (clip_path->antialias == antialias) {
if (polygon.num_edges == 0) {
status = _cairo_path_fixed_fill_to_polygon (&clip_path->path,
clip_path->tolerance,
&polygon);
fill_rule = clip_path->fill_rule;
polygon.limits = NULL;
polygon.num_limits = 0;
} else {
cairo_polygon_t next;
_cairo_polygon_init (&next, NULL, 0);
status = _cairo_path_fixed_fill_to_polygon (&clip_path->path,
clip_path->tolerance,
&next);
if (likely (status == CAIRO_INT_STATUS_SUCCESS))
status = _cairo_polygon_intersect (&polygon, fill_rule,
&next, clip_path->fill_rule);
_cairo_polygon_fini (&next);
fill_rule = CAIRO_FILL_RULE_WINDING;
}
if (unlikely (status))
goto error;
}
clip_path = clip_path->prev;
}
if (polygon.num_edges) {
_cairo_polygon_translate (&polygon, -extents->x, -extents->y);
status = _cairo_composite_rectangles_init_for_polygon (&composite, surface,
CAIRO_OPERATOR_IN,
&_cairo_pattern_white.base,
&polygon,
NULL);
if (unlikely (status))
goto cleanup_polygon;
status = composite_polygon (compositor, &composite,
&polygon, fill_rule, antialias);
_cairo_composite_rectangles_fini (&composite);
_cairo_polygon_fini (&polygon);
if (unlikely (status))
goto error;
}
return surface;
cleanup_polygon:
_cairo_polygon_fini (&polygon);
error:
cairo_surface_destroy (surface);
return _cairo_int_surface_create_in_error (status);
}
static cairo_int_status_t
fixup_unbounded_boxes (const cairo_spans_compositor_t *compositor,
const cairo_composite_rectangles_t *extents,
cairo_boxes_t *boxes)
{
cairo_boxes_t tmp, clear;
cairo_box_t box;
cairo_int_status_t status;
assert (boxes->is_pixel_aligned);
TRACE ((stderr, "%s\n", __FUNCTION__));
if (extents->bounded.width == extents->unbounded.width &&
extents->bounded.height == extents->unbounded.height)
{
return CAIRO_STATUS_SUCCESS;
}
/* subtract the drawn boxes from the unbounded area */
_cairo_boxes_init (&clear);
box.p1.x = _cairo_fixed_from_int (extents->unbounded.x + extents->unbounded.width);
box.p1.y = _cairo_fixed_from_int (extents->unbounded.y);
box.p2.x = _cairo_fixed_from_int (extents->unbounded.x);
box.p2.y = _cairo_fixed_from_int (extents->unbounded.y + extents->unbounded.height);
if (boxes->num_boxes) {
_cairo_boxes_init (&tmp);
status = _cairo_boxes_add (&tmp, CAIRO_ANTIALIAS_DEFAULT, &box);
assert (status == CAIRO_INT_STATUS_SUCCESS);
tmp.chunks.next = &boxes->chunks;
tmp.num_boxes += boxes->num_boxes;
status = _cairo_bentley_ottmann_tessellate_boxes (&tmp,
CAIRO_FILL_RULE_WINDING,
&clear);
tmp.chunks.next = NULL;
if (unlikely (status))
goto error;
} else {
box.p1.x = _cairo_fixed_from_int (extents->unbounded.x);
box.p2.x = _cairo_fixed_from_int (extents->unbounded.x + extents->unbounded.width);
status = _cairo_boxes_add (&clear, CAIRO_ANTIALIAS_DEFAULT, &box);
assert (status == CAIRO_INT_STATUS_SUCCESS);
}
/* If we have a clip polygon, we need to intersect with that as well */
if (extents->clip->path) {
status = fixup_unbounded_polygon (compositor, extents, &clear);
if (status == CAIRO_INT_STATUS_UNSUPPORTED)
status = fixup_unbounded_mask (compositor, extents, &clear);
} else {
/* Otherwise just intersect with the clip boxes */
if (extents->clip->num_boxes) {
_cairo_boxes_init_for_array (&tmp,
extents->clip->boxes,
extents->clip->num_boxes);
status = _cairo_boxes_intersect (&clear, &tmp, &clear);
if (unlikely (status))
goto error;
}
if (clear.is_pixel_aligned) {
status = compositor->fill_boxes (extents->surface,
CAIRO_OPERATOR_CLEAR,
CAIRO_COLOR_TRANSPARENT,
&clear);
} else {
cairo_composite_rectangles_t composite;
status = _cairo_composite_rectangles_init_for_boxes (&composite,
extents->surface,
CAIRO_OPERATOR_CLEAR,
&_cairo_pattern_clear.base,
&clear,
NULL);
if (likely (status == CAIRO_INT_STATUS_SUCCESS)) {
status = composite_boxes (compositor, &composite, &clear);
_cairo_composite_rectangles_fini (&composite);
}
}
}
error:
_cairo_boxes_fini (&clear);
return status;
}
