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/* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */
/* cairo - a vector graphics library with display and print output
*
* Copyright © 2002 University of Southern California
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
* The Original Code is the cairo graphics library.
*
* The Initial Developer of the Original Code is University of Southern
* California.
*
* Contributor(s):
* Carl D. Worth <cworth@cworth.org>
*/
#include "cairoint.h"
#include "cairo-boxes-private.h"
#include "cairo-error-private.h"
#include "cairo-path-fixed-private.h"
#include "cairo-region-private.h"
#include "cairo-traps-private.h"
typedef struct cairo_filler {
cairo_polygon_t *polygon;
double tolerance;
cairo_box_t limit;
cairo_bool_t has_limits;
cairo_point_t current_point;
cairo_point_t last_move_to;
} cairo_filler_t;
static cairo_status_t
_cairo_filler_line_to (void *closure,
const cairo_point_t *point)
{
cairo_filler_t *filler = closure;
cairo_status_t status;
status = _cairo_polygon_add_external_edge (filler->polygon,
&filler->current_point,
point);
filler->current_point = *point;
return status;
}
static cairo_status_t
_cairo_filler_close (void *closure)
{
cairo_filler_t *filler = closure;
/* close the subpath */
return _cairo_filler_line_to (closure, &filler->last_move_to);
}
static cairo_status_t
_cairo_filler_move_to (void *closure,
const cairo_point_t *point)
{
cairo_filler_t *filler = closure;
cairo_status_t status;
/* close current subpath */
status = _cairo_filler_close (closure);
if (unlikely (status))
return status;
/* make sure that the closure represents a degenerate path */
filler->current_point = *point;
filler->last_move_to = *point;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cairo_filler_curve_to (void *closure,
const cairo_point_t *p1,
const cairo_point_t *p2,
const cairo_point_t *p3)
{
cairo_filler_t *filler = closure;
cairo_spline_t spline;
if (filler->has_limits) {
if (! _cairo_spline_intersects (&filler->current_point, p1, p2, p3,
&filler->limit))
return _cairo_filler_line_to (filler, p3);
}
if (! _cairo_spline_init (&spline,
(cairo_spline_add_point_func_t)_cairo_filler_line_to, filler,
&filler->current_point, p1, p2, p3))
{
return _cairo_filler_line_to (closure, p3);
}
return _cairo_spline_decompose (&spline, filler->tolerance);
}
cairo_status_t
_cairo_path_fixed_fill_to_polygon (const cairo_path_fixed_t *path,
double tolerance,
cairo_polygon_t *polygon)
{
cairo_filler_t filler;
cairo_status_t status;
filler.polygon = polygon;
filler.tolerance = tolerance;
filler.has_limits = FALSE;
if (polygon->num_limits) {
filler.has_limits = TRUE;
filler.limit = polygon->limit;
}
/* make sure that the closure represents a degenerate path */
filler.current_point.x = 0;
filler.current_point.y = 0;
filler.last_move_to = filler.current_point;
status = _cairo_path_fixed_interpret (path,
_cairo_filler_move_to,
_cairo_filler_line_to,
_cairo_filler_curve_to,
_cairo_filler_close,
&filler);
if (unlikely (status))
return status;
return _cairo_filler_close (&filler);
}
typedef struct cairo_filler_rectilinear_aligned {
cairo_polygon_t *polygon;
cairo_point_t current_point;
cairo_point_t last_move_to;
} cairo_filler_ra_t;
static cairo_status_t
_cairo_filler_ra_line_to (void *closure,
const cairo_point_t *point)
{
cairo_filler_ra_t *filler = closure;
cairo_status_t status;
cairo_point_t p;
p.x = _cairo_fixed_round_down (point->x);
p.y = _cairo_fixed_round_down (point->y);
status = _cairo_polygon_add_external_edge (filler->polygon,
&filler->current_point,
&p);
filler->current_point = p;
return status;
}
static cairo_status_t
_cairo_filler_ra_close (void *closure)
{
cairo_filler_ra_t *filler = closure;
return _cairo_filler_ra_line_to (closure, &filler->last_move_to);
}
static cairo_status_t
_cairo_filler_ra_move_to (void *closure,
const cairo_point_t *point)
{
cairo_filler_ra_t *filler = closure;
cairo_status_t status;
cairo_point_t p;
/* close current subpath */
status = _cairo_filler_ra_close (closure);
if (unlikely (status))
return status;
p.x = _cairo_fixed_round_down (point->x);
p.y = _cairo_fixed_round_down (point->y);
/* make sure that the closure represents a degenerate path */
filler->current_point = p;
filler->last_move_to = p;
return CAIRO_STATUS_SUCCESS;
}
cairo_status_t
_cairo_path_fixed_fill_rectilinear_to_polygon (const cairo_path_fixed_t *path,
cairo_antialias_t antialias,
cairo_polygon_t *polygon)
{
cairo_filler_ra_t filler;
cairo_status_t status;
if (antialias != CAIRO_ANTIALIAS_NONE)
return _cairo_path_fixed_fill_to_polygon (path, 0., polygon);
filler.polygon = polygon;
/* make sure that the closure represents a degenerate path */
filler.current_point.x = 0;
filler.current_point.y = 0;
filler.last_move_to = filler.current_point;
status = _cairo_path_fixed_interpret_flat (path,
_cairo_filler_ra_move_to,
_cairo_filler_ra_line_to,
_cairo_filler_ra_close,
&filler,
0.);
if (unlikely (status))
return status;
return _cairo_filler_ra_close (&filler);
}
cairo_status_t
_cairo_path_fixed_fill_to_traps (const cairo_path_fixed_t *path,
cairo_fill_rule_t fill_rule,
double tolerance,
cairo_traps_t *traps)
{
cairo_polygon_t polygon;
cairo_status_t status;
if (_cairo_path_fixed_fill_is_empty (path))
return CAIRO_STATUS_SUCCESS;
_cairo_polygon_init (&polygon, traps->limits, traps->num_limits);
status = _cairo_path_fixed_fill_to_polygon (path, tolerance, &polygon);
if (unlikely (status || polygon.num_edges == 0))
goto CLEANUP;
status = _cairo_bentley_ottmann_tessellate_polygon (traps,
&polygon, fill_rule);
CLEANUP:
_cairo_polygon_fini (&polygon);
return status;
}
static cairo_status_t
_cairo_path_fixed_fill_rectilinear_tessellate_to_boxes (const cairo_path_fixed_t *path,
cairo_fill_rule_t fill_rule,
cairo_antialias_t antialias,
cairo_boxes_t *boxes)
{
cairo_polygon_t polygon;
cairo_status_t status;
_cairo_polygon_init (&polygon, boxes->limits, boxes->num_limits);
boxes->num_limits = 0;
/* tolerance will be ignored as the path is rectilinear */
status = _cairo_path_fixed_fill_rectilinear_to_polygon (path, antialias, &polygon);
if (likely (status == CAIRO_STATUS_SUCCESS)) {
status =
_cairo_bentley_ottmann_tessellate_rectilinear_polygon_to_boxes (&polygon,
fill_rule,
boxes);
}
_cairo_polygon_fini (&polygon);
return status;
}
cairo_status_t
_cairo_path_fixed_fill_rectilinear_to_boxes (const cairo_path_fixed_t *path,
cairo_fill_rule_t fill_rule,
cairo_antialias_t antialias,
cairo_boxes_t *boxes)
{
cairo_path_fixed_iter_t iter;
cairo_status_t status;
cairo_box_t box;
if (_cairo_path_fixed_is_box (path, &box))
return _cairo_boxes_add (boxes, antialias, &box);
_cairo_path_fixed_iter_init (&iter, path);
while (_cairo_path_fixed_iter_is_fill_box (&iter, &box)) {
if (box.p1.y == box.p2.y || box.p1.x == box.p2.x)
continue;
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_boxes_add (boxes, antialias, &box);
if (unlikely (status))
return status;
}
if (_cairo_path_fixed_iter_at_end (&iter))
return _cairo_bentley_ottmann_tessellate_boxes (boxes, fill_rule, boxes);
/* path is not rectangular, try extracting clipped rectilinear edges */
_cairo_boxes_clear (boxes);
return _cairo_path_fixed_fill_rectilinear_tessellate_to_boxes (path,
fill_rule,
antialias,
boxes);
}