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/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */
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/* cairo - a vector graphics library with display and print output
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 *
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 * Copyright © 2002 University of Southern California
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it either under the terms of the GNU Lesser General Public
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 * License version 2.1 as published by the Free Software Foundation
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 * (the "LGPL") or, at your option, under the terms of the Mozilla
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 * Public License Version 1.1 (the "MPL"). If you do not alter this
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 * notice, a recipient may use your version of this file under either
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 * the MPL or the LGPL.
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 *
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 * You should have received a copy of the LGPL along with this library
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 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
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 * You should have received a copy of the MPL along with this library
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 * in the file COPYING-MPL-1.1
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 *
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 * The contents of this file are subject to the Mozilla Public License
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 * Version 1.1 (the "License"); you may not use this file except in
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 * compliance with the License. You may obtain a copy of the License at
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 * http://www.mozilla.org/MPL/
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 *
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 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
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 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
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 * the specific language governing rights and limitations.
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 *
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 * The Original Code is the cairo graphics library.
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 *
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 * The Initial Developer of the Original Code is University of Southern
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 * California.
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 *
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 * Contributor(s):
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 *	Carl D. Worth <cworth@cworth.org>
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 *	Chris Wilson <chris@chris-wilson.co.uk>
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 */
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#include "cairoint.h"
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#include "cairo-stroke-dash-private.h"
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void
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5820
_cairo_stroker_dash_start (cairo_stroker_dash_t *dash)
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{
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    double offset;
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5820
    cairo_bool_t on = TRUE;
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5820
    unsigned int i = 0;
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5820
    if (! dash->dashed)
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2502
	return;
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3318
    offset = dash->dash_offset;
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    /* We stop searching for a starting point as soon as the
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       offset reaches zero.  Otherwise when an initial dash
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       segment shrinks to zero it will be skipped over. */
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4572
    while (offset > 0.0 && offset >= dash->dashes[i]) {
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1254
	offset -= dash->dashes[i];
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1254
	on = !on;
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1254
	if (++i == dash->num_dashes)
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	    i = 0;
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    }
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3318
    dash->dash_index = i;
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3318
    dash->dash_on = dash->dash_starts_on = on;
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3318
    dash->dash_remain = dash->dashes[i] - offset;
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}
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void
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22590
_cairo_stroker_dash_step (cairo_stroker_dash_t *dash, double step)
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{
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22590
    dash->dash_remain -= step;
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22590
    if (dash->dash_remain < CAIRO_FIXED_ERROR_DOUBLE) {
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16410
	if (++dash->dash_index == dash->num_dashes)
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8436
	    dash->dash_index = 0;
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16410
	dash->dash_on = ! dash->dash_on;
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16410
	dash->dash_remain += dash->dashes[dash->dash_index];
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    }
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22590
}
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void
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3213
_cairo_stroker_dash_init (cairo_stroker_dash_t *dash,
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			  const cairo_stroke_style_t *style)
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{
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3213
    dash->dashed = style->dash != NULL;
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3213
    if (! dash->dashed)
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1902
	return;
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    dash->dashes = style->dash;
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    dash->num_dashes = style->num_dashes;
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    dash->dash_offset = style->dash_offset;
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1311
    _cairo_stroker_dash_start (dash);
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}