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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 under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Author: Carl D. Worth <cworth@isi.edu>
 */

#include "cairoint.h"

typedef struct cairo_path_bounder {
    int has_point;

    cairo_fixed_t min_x;
    cairo_fixed_t min_y;
    cairo_fixed_t max_x;
    cairo_fixed_t max_y;
} cairo_path_bounder_t;

static void
_cairo_path_bounder_init (cairo_path_bounder_t *bounder);

static void
_cairo_path_bounder_fini (cairo_path_bounder_t *bounder);

static cairo_status_t
_cairo_path_bounder_add_point (cairo_path_bounder_t *bounder, cairo_point_t *point);

static cairo_status_t
_cairo_path_bounder_move_to (void *closure, cairo_point_t *point);

static cairo_status_t
_cairo_path_bounder_line_to (void *closure, cairo_point_t *point);

static cairo_status_t
_cairo_path_bounder_curve_to (void *closure,
			      cairo_point_t *b,
			      cairo_point_t *c,
			      cairo_point_t *d);

static cairo_status_t
_cairo_path_bounder_close_path (void *closure);

static void
_cairo_path_bounder_init (cairo_path_bounder_t *bounder)
{
    bounder->has_point = 0;
}

static void
_cairo_path_bounder_fini (cairo_path_bounder_t *bounder)
{
    bounder->has_point = 0;
}

static cairo_status_t
_cairo_path_bounder_add_point (cairo_path_bounder_t *bounder, cairo_point_t *point)
{
    if (bounder->has_point) {
	if (point->x < bounder->min_x)
	    bounder->min_x = point->x;
	
	if (point->y < bounder->min_y)
	    bounder->min_y = point->y;
	
	if (point->x > bounder->max_x)
	    bounder->max_x = point->x;
	
	if (point->y > bounder->max_y)
	    bounder->max_y = point->y;
    } else {
	bounder->min_x = point->x;
	bounder->min_y = point->y;
	bounder->max_x = point->x;
	bounder->max_y = point->y;

	bounder->has_point = 1;
    }
	
    return CAIRO_STATUS_SUCCESS;
}

static cairo_status_t
_cairo_path_bounder_move_to (void *closure, cairo_point_t *point)
{
    cairo_path_bounder_t *bounder = closure;

    _cairo_path_bounder_add_point (bounder, point);

    return CAIRO_STATUS_SUCCESS;
}

static cairo_status_t
_cairo_path_bounder_line_to (void *closure, cairo_point_t *point)
{
    cairo_path_bounder_t *bounder = closure;

    _cairo_path_bounder_add_point (bounder, point);

    return CAIRO_STATUS_SUCCESS;
}

static cairo_status_t
_cairo_path_bounder_curve_to (void *closure,
			      cairo_point_t *b,
			      cairo_point_t *c,
			      cairo_point_t *d)
{
    cairo_path_bounder_t *bounder = closure;

    _cairo_path_bounder_add_point (bounder, b);
    _cairo_path_bounder_add_point (bounder, c);
    _cairo_path_bounder_add_point (bounder, d);

    return CAIRO_STATUS_SUCCESS;
}

static cairo_status_t
_cairo_path_bounder_close_path (void *closure)
{
    return CAIRO_STATUS_SUCCESS;
}

/* XXX: Perhaps this should compute a PixRegion rather than 4 doubles */
cairo_status_t
_cairo_path_bounds (cairo_path_t *path, double *x1, double *y1, double *x2, double *y2)
{
    cairo_status_t status;

    cairo_path_bounder_t bounder;

    _cairo_path_bounder_init (&bounder);

    status = _cairo_path_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);
    if (status) {
	*x1 = *y1 = *x2 = *y2 = 0.0;
	_cairo_path_bounder_fini (&bounder);
	return status;
    }

    *x1 = _cairo_fixed_to_double (bounder.min_x);
    *y1 = _cairo_fixed_to_double (bounder.min_y);
    *x2 = _cairo_fixed_to_double (bounder.max_x);
    *y2 = _cairo_fixed_to_double (bounder.max_y);

    _cairo_path_bounder_fini (&bounder);

    return CAIRO_STATUS_SUCCESS;
}