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/* 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

 * http://www.mozilla.org/MPL/

 *

 * 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 

 */

#include "cairoint.h"

#include "cairo-path-fixed-private.h"

typedef struct cairo_path_bounder {

    cairo_point_t current_point;

    cairo_bool_t has_initial_point;

    cairo_bool_t has_point;

    cairo_box_t extents;

} cairo_path_bounder_t;

static void

_cairo_path_bounder_init (cairo_path_bounder_t *bounder)

{

    bounder->has_initial_point = FALSE;

    bounder->has_point = FALSE;

}

static void

_cairo_path_bounder_add_point (cairo_path_bounder_t *bounder,

			       const cairo_point_t *point)

{

    if (bounder->has_point) {

	if (point->x < bounder->extents.p1.x)

	    bounder->extents.p1.x = point->x;

	if (point->y < bounder->extents.p1.y)

	    bounder->extents.p1.y = point->y;

	if (point->x > bounder->extents.p2.x)

	    bounder->extents.p2.x = point->x;

	if (point->y > bounder->extents.p2.y)

	    bounder->extents.p2.y = point->y;

    } else {

	bounder->extents.p1.x = point->x;

	bounder->extents.p1.y = point->y;

	bounder->extents.p2.x = point->x;

	bounder->extents.p2.y = point->y;

	bounder->has_point = TRUE;

    }

}

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;

    bounder->has_initial_point = TRUE;

    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;

    if (bounder->has_initial_point) {

	_cairo_path_bounder_add_point (bounder, &bounder->current_point);

	bounder->has_initial_point = FALSE;

    }

    _cairo_path_bounder_add_point (bounder, point);

    bounder->current_point = *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;

    /* If the bbox of the control points is entirely inside, then we

     * do not need to further evaluate the spline.

     */

    if (! bounder->has_point ||

	b->x < bounder->extents.p1.x || b->x > bounder->extents.p2.x ||

	b->y < bounder->extents.p1.y || b->y > bounder->extents.p2.y ||

	c->x < bounder->extents.p1.x || c->x > bounder->extents.p2.x ||

	c->y < bounder->extents.p1.y || c->y > bounder->extents.p2.y ||

	d->x < bounder->extents.p1.x || d->x > bounder->extents.p2.x ||

	d->y < bounder->extents.p1.y || d->y > bounder->extents.p2.y)

    {

	return _cairo_spline_bound (_cairo_path_bounder_line_to, bounder,

				    &bounder->current_point, b, c, d);

    }

    else

    {

	/* All control points are within the current extents. */

	bounder->current_point = *d;

	return CAIRO_STATUS_SUCCESS;

    }

}

static cairo_status_t

_cairo_path_bounder_close_path (void *closure)

{

    return CAIRO_STATUS_SUCCESS;

}

/* This computes the extents of all the points in the path, not those of

 * the damage area (i.e it does not consider winding and it only inspects

 * the control points of the curves, not the flattened path).

 */

void

_cairo_path_fixed_approximate_clip_extents (const cairo_path_fixed_t *path,

					    cairo_rectangle_int_t *extents)

{

    if (path->extents.p1.x < path->extents.p2.x) {

	_cairo_box_round_to_rectangle (&path->extents, extents);

    } else {

	extents->x = extents->y = 0;

	extents->width = extents->height = 0;

    }

}

/* A slightly better approximation than above - we actually decompose the

 * Bezier, but we continue to ignore winding.

 */

void

_cairo_path_fixed_approximate_fill_extents (const cairo_path_fixed_t *path,

					    cairo_rectangle_int_t *extents)

{

    cairo_path_bounder_t bounder;

    cairo_status_t status;

    if (! path->has_curve_to) {

	bounder.extents = path->extents;

	bounder.has_point = path->extents.p1.x < path->extents.p2.x;

    } else {

	_cairo_path_bounder_init (&bounder);

	status = _cairo_path_fixed_interpret (path, CAIRO_DIRECTION_FORWARD,

					      _cairo_path_bounder_move_to,

					      _cairo_path_bounder_line_to,

					      _cairo_path_bounder_curve_to,

					      _cairo_path_bounder_close_path,

					      &bounder);

	assert (status == CAIRO_STATUS_SUCCESS);

    }

    if (bounder.has_point) {

	_cairo_box_round_to_rectangle (&bounder.extents, extents);

    } else {

	extents->x = extents->y = 0;

	extents->width = extents->height = 0;

    }

}

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)

{

    cairo_path_bounder_t bounder;

    cairo_status_t status;

    if (! path->has_curve_to) {

	bounder.extents = path->extents;

	bounder.has_point = path->extents.p1.x < path->extents.p2.x;

    } else {

	_cairo_path_bounder_init (&bounder);

	status = _cairo_path_fixed_interpret_flat (path, CAIRO_DIRECTION_FORWARD,

						   _cairo_path_bounder_move_to,

						   _cairo_path_bounder_line_to,

						   _cairo_path_bounder_close_path,

						   &bounder, tolerance);

	assert (status == CAIRO_STATUS_SUCCESS);

    }

    if (bounder.has_point) {

	_cairo_box_round_to_rectangle (&bounder.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_rectangle_int_t *extents)

{

    cairo_path_bounder_t bounder;

    cairo_status_t status;

    if (! path->has_curve_to) {

	bounder.extents = path->extents;

	/* include trailing move-to for degenerate segments */

	if (path->has_last_move_point) {

	    const cairo_point_t *point = &path->last_move_point;

	    if (point->x < bounder.extents.p1.x)

		bounder.extents.p1.x = point->x;

	    if (point->y < bounder.extents.p1.y)

		bounder.extents.p1.y = point->y;

	    if (point->x > bounder.extents.p2.x)

		bounder.extents.p2.x = point->x;

	    if (point->y > bounder.extents.p2.y)

		bounder.extents.p2.y = point->y;

	}

	bounder.has_point = bounder.extents.p1.x <= bounder.extents.p2.x;

	bounder.has_initial_point = FALSE;

    } else {

	_cairo_path_bounder_init (&bounder);

	status = _cairo_path_fixed_interpret (path, CAIRO_DIRECTION_FORWARD,

					      _cairo_path_bounder_move_to,

					      _cairo_path_bounder_line_to,

					      _cairo_path_bounder_curve_to,

					      _cairo_path_bounder_close_path,

					      &bounder);

	assert (status == CAIRO_STATUS_SUCCESS);

    }

    if (bounder.has_point) {

	double dx, dy;

	_cairo_stroke_style_max_distance_from_path (style, ctm, &dx, &dy);

	bounder.extents.p1.x -= _cairo_fixed_from_double (dx);

	bounder.extents.p2.x += _cairo_fixed_from_double (dx);

	bounder.extents.p1.y -= _cairo_fixed_from_double (dy);

	bounder.extents.p2.y += _cairo_fixed_from_double (dy);

	_cairo_box_round_to_rectangle (&bounder.extents, extents);

    } else if (bounder.has_initial_point) {

	double dx, dy;

	/* accommodate capping of degenerate paths */

	_cairo_stroke_style_max_distance_from_path (style, ctm, &dx, &dy);

	bounder.extents.p1.x = bounder.current_point.x - _cairo_fixed_from_double (dx);

	bounder.extents.p2.x = bounder.current_point.x + _cairo_fixed_from_double (dx);

	bounder.extents.p1.y = bounder.current_point.y - _cairo_fixed_from_double (dy);

	bounder.extents.p2.y = bounder.current_point.y + _cairo_fixed_from_double (dy);

	_cairo_box_round_to_rectangle (&bounder.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_traps_t traps;

    cairo_box_t bbox;

    cairo_status_t status;

    _cairo_traps_init (&traps);

    status = _cairo_path_fixed_stroke_to_traps (path,

						stroke_style,

						ctm,

						ctm_inverse,

						tolerance,

						&traps);

    _cairo_traps_extents (&traps, &bbox);

    _cairo_traps_fini (&traps);

    _cairo_box_round_to_rectangle (&bbox, extents);

    return status;

}

cairo_bool_t

_cairo_path_fixed_extents (const cairo_path_fixed_t *path,

			   cairo_box_t *box)

{

    cairo_path_bounder_t bounder;

    cairo_status_t status;

    if (! path->has_curve_to) {

	*box = path->extents;

	/* empty extents should still have an origin and should not

	 * be {0, 0, 0, 0} */

	return path->extents.p1.x <= path->extents.p2.x;

    }

    _cairo_path_bounder_init (&bounder);

    status = _cairo_path_fixed_interpret (path, CAIRO_DIRECTION_FORWARD,

					  _cairo_path_bounder_move_to,

					  _cairo_path_bounder_line_to,

					  _cairo_path_bounder_curve_to,

					  _cairo_path_bounder_close_path,

					  &bounder);

    assert (status == CAIRO_STATUS_SUCCESS);

    *box = bounder.extents;

    return bounder.has_point;

}