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/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */
/* cairo - a vector graphics library with display and print output
*
* Copyright © 2003 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-box-inline.h"
#include "cairo-error-private.h"
#include "cairo-path-fixed-private.h"
typedef struct _cairo_path_bounder {
cairo_point_t current_point;
cairo_bool_t has_extents;
cairo_box_t extents;
} cairo_path_bounder_t;
static cairo_status_t
_cairo_path_bounder_move_to (void *closure,
const cairo_point_t *point)
{
cairo_path_bounder_t *bounder = closure;
bounder->current_point = *point;
if (likely (bounder->has_extents)) {
_cairo_box_add_point (&bounder->extents, point);
} else {
bounder->has_extents = TRUE;
_cairo_box_set (&bounder->extents, point, point);
}
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cairo_path_bounder_line_to (void *closure,
const cairo_point_t *point)
{
cairo_path_bounder_t *bounder = closure;
bounder->current_point = *point;
_cairo_box_add_point (&bounder->extents, point);
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cairo_path_bounder_curve_to (void *closure,
const cairo_point_t *b,
const cairo_point_t *c,
const cairo_point_t *d)
{
cairo_path_bounder_t *bounder = closure;
_cairo_box_add_curve_to (&bounder->extents,
&bounder->current_point,
b, c, d);
bounder->current_point = *d;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cairo_path_bounder_close_path (void *closure)
{
return CAIRO_STATUS_SUCCESS;
}
cairo_bool_t
_cairo_path_bounder_extents (const cairo_path_fixed_t *path,
cairo_box_t *extents)
{
cairo_path_bounder_t bounder;
cairo_status_t status;
bounder.has_extents = FALSE;
status = _cairo_path_fixed_interpret (path,
_cairo_path_bounder_move_to,
_cairo_path_bounder_line_to,
_cairo_path_bounder_curve_to,
_cairo_path_bounder_close_path,
&bounder);
assert (!status);
if (bounder.has_extents)
*extents = bounder.extents;
return bounder.has_extents;
}
void
_cairo_path_fixed_approximate_clip_extents (const cairo_path_fixed_t *path,
cairo_rectangle_int_t *extents)
{
_cairo_path_fixed_approximate_fill_extents (path, extents);
}
void
_cairo_path_fixed_approximate_fill_extents (const cairo_path_fixed_t *path,
cairo_rectangle_int_t *extents)
{
_cairo_path_fixed_fill_extents (path, CAIRO_FILL_RULE_WINDING, 0, extents);
}
void
_cairo_path_fixed_fill_extents (const cairo_path_fixed_t *path,
cairo_fill_rule_t fill_rule,
double tolerance,
cairo_rectangle_int_t *extents)
{
if (path->extents.p1.x < path->extents.p2.x &&
path->extents.p1.y < path->extents.p2.y) {
_cairo_box_round_to_rectangle (&path->extents, extents);
} else {
extents->x = extents->y = 0;
extents->width = extents->height = 0;
}
}
/* Adjusts the fill extents (above) by the device-space pen. */
void
_cairo_path_fixed_approximate_stroke_extents (const cairo_path_fixed_t *path,
const cairo_stroke_style_t *style,
const cairo_matrix_t *ctm,
cairo_bool_t is_vector,
cairo_rectangle_int_t *extents)
{
if (path->has_extents) {
cairo_box_t box_extents;
double dx, dy;
_cairo_stroke_style_max_distance_from_path (style, path, ctm, &dx, &dy);
if (is_vector)
{
/* When calculating extents for vector surfaces, ensure lines thinner
* than the fixed point resolution are not optimized away. */
double min = _cairo_fixed_to_double (CAIRO_FIXED_EPSILON*2);
if (dx < min)
dx = min;
if (dy < min)
dy = min;
}
box_extents = path->extents;
box_extents.p1.x -= _cairo_fixed_from_double (dx);
box_extents.p1.y -= _cairo_fixed_from_double (dy);
box_extents.p2.x += _cairo_fixed_from_double (dx);
box_extents.p2.y += _cairo_fixed_from_double (dy);
_cairo_box_round_to_rectangle (&box_extents, extents);
} else {
extents->x = extents->y = 0;
extents->width = extents->height = 0;
}
}
cairo_status_t
_cairo_path_fixed_stroke_extents (const cairo_path_fixed_t *path,
const cairo_stroke_style_t *stroke_style,
const cairo_matrix_t *ctm,
const cairo_matrix_t *ctm_inverse,
double tolerance,
cairo_rectangle_int_t *extents)
{
cairo_polygon_t polygon;
cairo_status_t status;
cairo_stroke_style_t style;
/* When calculating extents for vector surfaces, ensure lines thinner
* than one point are not optimized away. */
double min_line_width = _cairo_matrix_transformed_circle_major_axis (ctm_inverse, 1.0);
if (stroke_style->line_width < min_line_width)
{
style = *stroke_style;
style.line_width = min_line_width;
stroke_style = &style;
}
_cairo_polygon_init (&polygon, NULL, 0);
status = _cairo_path_fixed_stroke_to_polygon (path,
stroke_style,
ctm, ctm_inverse,
tolerance,
&polygon);
_cairo_box_round_to_rectangle (&polygon.extents, extents);
_cairo_polygon_fini (&polygon);
return status;
}
cairo_bool_t
_cairo_path_fixed_extents (const cairo_path_fixed_t *path,
cairo_box_t *box)
{
*box = path->extents;
return path->has_extents;
}