static cairo_int_status_t
clip_and_composite_polygon (const cairo_spans_compositor_t *compositor,
cairo_composite_rectangles_t *extents,
cairo_polygon_t *polygon,
cairo_fill_rule_t fill_rule,
cairo_antialias_t antialias)
{
cairo_int_status_t status;
/* XXX simply uses polygon limits.point extemities, tessellation? */
status = trim_extents_to_polygon (extents, polygon);
if (unlikely (status))
return status;
if (_cairo_polygon_is_empty (polygon)) {
cairo_boxes_t boxes;
if (extents->is_bounded)
return CAIRO_STATUS_SUCCESS;
_cairo_boxes_init (&boxes);
extents->bounded.width = extents->bounded.height = 0;
return fixup_unbounded_boxes (compositor, extents, &boxes);
}
if (extents->is_bounded && extents->clip->path) {
cairo_polygon_t clipper;
cairo_antialias_t clip_antialias;
cairo_fill_rule_t clip_fill_rule;
status = _cairo_clip_get_polygon (extents->clip,
&clipper,
&clip_fill_rule,
&clip_antialias);
if (likely (status == CAIRO_INT_STATUS_SUCCESS)) {
cairo_clip_t *old_clip;
if (clip_antialias == antialias) {
/* refresh limits after trimming extents */
_cairo_polygon_limit_to_clip(polygon, extents->clip);
status = _cairo_polygon_intersect (polygon, fill_rule,
&clipper, clip_fill_rule);
_cairo_polygon_fini (&clipper);
if (unlikely (status))
return status;
old_clip = extents->clip;
extents->clip = _cairo_clip_copy_region (extents->clip);
_cairo_clip_destroy (old_clip);
} else {
_cairo_polygon_fini (&clipper);
}
}
}
return composite_polygon (compositor, extents,
polygon, fill_rule, antialias);
}
static cairo_int_status_t
fixup_unbounded_polygon (const cairo_spans_compositor_t *compositor,
const cairo_composite_rectangles_t *extents,
cairo_boxes_t *boxes)
{
cairo_polygon_t polygon, intersect;
cairo_composite_rectangles_t composite;
cairo_fill_rule_t fill_rule;
cairo_antialias_t antialias;
cairo_int_status_t status;
TRACE((stderr, "%s\n", __FUNCTION__));
/* Can we treat the clip as a regular clear-polygon and use it to fill? */
status = _cairo_clip_get_polygon (extents->clip, &polygon,
&fill_rule, &antialias);
if (status == CAIRO_INT_STATUS_UNSUPPORTED)
return status;
status= _cairo_polygon_init_boxes (&intersect, boxes);
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;
status = _cairo_composite_rectangles_init_for_polygon (&composite,
extents->surface,
CAIRO_OPERATOR_CLEAR,
&_cairo_pattern_clear.base,
&polygon,
NULL);
if (unlikely (status))
goto cleanup_polygon;
status = composite_polygon (compositor, &composite,
&polygon, fill_rule, antialias);
_cairo_composite_rectangles_fini (&composite);
cleanup_polygon:
_cairo_polygon_fini (&polygon);
return status;
}
cairo_int_status_t
_cairo_gl_msaa_compositor_draw_clip (cairo_gl_context_t *ctx,
cairo_gl_composite_t *setup,
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;
if (! clip)
return CAIRO_INT_STATUS_UNSUPPORTED;
if (clip->num_boxes == 1 && ! clip->path)
return _cairo_gl_msaa_compositor_draw_quad (ctx, setup,
&clip->boxes[0]);
if (traps->num_traps == 0) {
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.
*/
status = _cairo_bentley_ottmann_tessellate_polygon (traps,
&polygon,
fill_rule);
_cairo_polygon_fini (&polygon);
if (unlikely (status))
return status;
}
status = _draw_traps (ctx, setup, traps);
return status;
}
static cairo_int_status_t
_draw_clip (cairo_gl_context_t *ctx,
cairo_gl_composite_t *setup,
cairo_clip_t *clip)
{
cairo_int_status_t status;
cairo_traps_t traps;
cairo_polygon_t polygon;
cairo_antialias_t antialias;
cairo_fill_rule_t fill_rule;
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);
if (unlikely (status))
return status;
status = _draw_traps (ctx, setup, &traps);
_cairo_traps_fini (&traps);
return status;
}
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;
}
static cairo_int_status_t
clip_and_composite_boxes (const cairo_spans_compositor_t *compositor,
cairo_composite_rectangles_t *extents,
cairo_boxes_t *boxes)
{
cairo_int_status_t status;
cairo_polygon_t polygon;
TRACE ((stderr, "%s\n", __FUNCTION__));
status = trim_extents_to_boxes (extents, boxes);
if (unlikely (status))
return status;
if (boxes->num_boxes == 0) {
if (extents->is_bounded)
return CAIRO_STATUS_SUCCESS;
return fixup_unbounded_boxes (compositor, extents, boxes);
}
/* Can we reduce drawing through a clip-mask to simply drawing the clip? */
if (extents->clip->path != NULL && extents->is_bounded) {
cairo_polygon_t polygon;
cairo_fill_rule_t fill_rule;
cairo_antialias_t antialias;
cairo_clip_t *clip;
clip = _cairo_clip_copy (extents->clip);
clip = _cairo_clip_intersect_boxes (clip, boxes);
if (_cairo_clip_is_all_clipped (clip))
return CAIRO_INT_STATUS_NOTHING_TO_DO;
status = _cairo_clip_get_polygon (clip, &polygon,
&fill_rule, &antialias);
_cairo_clip_path_destroy (clip->path);
clip->path = NULL;
if (likely (status == CAIRO_INT_STATUS_SUCCESS)) {
cairo_clip_t *saved_clip = extents->clip;
extents->clip = clip;
status = clip_and_composite_polygon (compositor, extents, &polygon,
fill_rule, antialias);
clip = extents->clip;
extents->clip = saved_clip;
_cairo_polygon_fini (&polygon);
}
_cairo_clip_destroy (clip);
if (status != CAIRO_INT_STATUS_UNSUPPORTED)
return status;
}
if (boxes->is_pixel_aligned) {
status = composite_aligned_boxes (compositor, extents, boxes);
if (status != CAIRO_INT_STATUS_UNSUPPORTED)
return status;
}
status = composite_boxes (compositor, extents, boxes);
if (status != CAIRO_INT_STATUS_UNSUPPORTED)
return status;
status = _cairo_polygon_init_boxes (&polygon, boxes);
if (unlikely (status))
return status;
status = composite_polygon (compositor, extents, &polygon,
CAIRO_FILL_RULE_WINDING,
CAIRO_ANTIALIAS_DEFAULT);
_cairo_polygon_fini (&polygon);
return status;
}
static cairo_int_status_t
clip_and_composite_polygon (const cairo_spans_compositor_t *compositor,
cairo_composite_rectangles_t *extents,
cairo_polygon_t *polygon,
cairo_fill_rule_t fill_rule,
cairo_antialias_t antialias)
{
cairo_int_status_t status;
TRACE ((stderr, "%s\n", __FUNCTION__));
/* XXX simply uses polygon limits.point extemities, tessellation? */
status = trim_extents_to_polygon (extents, polygon);
if (unlikely (status))
return status;
if (_cairo_polygon_is_empty (polygon)) {
cairo_boxes_t boxes;
if (extents->is_bounded)
return CAIRO_STATUS_SUCCESS;
_cairo_boxes_init (&boxes);
extents->bounded.width = extents->bounded.height = 0;
return fixup_unbounded_boxes (compositor, extents, &boxes);
}
if (extents->is_bounded && extents->clip->path) {
cairo_polygon_t clipper;
cairo_antialias_t clip_antialias;
cairo_fill_rule_t clip_fill_rule;
TRACE((stderr, "%s - combining shape with clip polygon\n",
__FUNCTION__));
status = _cairo_clip_get_polygon (extents->clip,
&clipper,
&clip_fill_rule,
&clip_antialias);
if (likely (status == CAIRO_INT_STATUS_SUCCESS)) {
cairo_clip_t *old_clip;
if (clip_antialias == antialias) {
status = _cairo_polygon_intersect (polygon, fill_rule,
&clipper, clip_fill_rule);
_cairo_polygon_fini (&clipper);
if (unlikely (status))
return status;
old_clip = extents->clip;
extents->clip = _cairo_clip_copy_region (extents->clip);
_cairo_clip_destroy (old_clip);
status = trim_extents_to_polygon (extents, polygon);
if (unlikely (status))
return status;
fill_rule = CAIRO_FILL_RULE_WINDING;
} else {
_cairo_polygon_fini (&clipper);
}
}
}
return composite_polygon (compositor, extents,
polygon, fill_rule, antialias);
}