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/*
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 * Copyright © 2005 Red Hat, Inc.
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 *
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 * Permission to use, copy, modify, distribute, and sell this software
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 * and its documentation for any purpose is hereby granted without
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 * fee, provided that the above copyright notice appear in all copies
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 * and that both that copyright notice and this permission notice
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 * appear in supporting documentation, and that the name of
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 * Red Hat, Inc. not be used in advertising or publicity pertaining to
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 * distribution of the software without specific, written prior
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 * permission. Red Hat, Inc. makes no representations about the
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 * suitability of this software for any purpose.  It is provided "as
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 * is" without express or implied warranty.
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 *
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 * RED HAT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
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 * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
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 * FITNESS, IN NO EVENT SHALL RED HAT, INC. BE LIABLE FOR ANY SPECIAL,
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 * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
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 * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
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 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
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 * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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 *
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 * Author: Carl D. Worth <cworth@cworth.org>
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 */
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#include "cairo-test.h"
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#define SIZE 30
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/* At one point, an optimization was proposed for cairo in which a
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 * curve_to would be optimized as a line_to. The initial (buggy)
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 * implementation verified that the slopes of several segments of the
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 * spline's control polygon were identical, but left open the
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 * possibility of an anti-parallel slope for one segment.
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 *
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 * For example, given a spline with collinear control points (A,B,C,D)
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 * positioned as follows:
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 *
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 *	C--A--B--D
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 *
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 * The code verified identical slopes for AB, CD, and AD. The missing
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 * check for the BC segment allowed it to be anti-parallel to the
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 * others as above, and hence invalid to replace this spline with the
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 * AD line segment.
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 */
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static cairo_test_status_t
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3
draw (cairo_t *cr, int width, int height)
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{
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3
    cairo_set_source_rgb (cr, 1.0, 1.0, 1.0); /* white */
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3
    cairo_paint (cr);
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3
    cairo_set_line_width (cr, 1.0);
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3
    cairo_set_line_cap (cr, CAIRO_LINE_CAP_BUTT);
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3
    cairo_set_line_join (cr, CAIRO_LINE_JOIN_BEVEL);
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    cairo_set_source_rgb (cr, 0.0, 0.0, 0.0); /* black */
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    cairo_translate (cr, 0, 1.0);
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    /* The CABD spline as described above. We ensure that the spline
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     * folds over on itself outside the bounds of the image to avoid
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     * the reference image having the curved portion of that fold,
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     * (which would just be harder to match in all the backends than
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     * we really want). */
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3
    cairo_move_to (cr,
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		     10.5, 0.5);
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3
    cairo_curve_to (cr,
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		     11.5, 0.5,
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		    -25.0, 0.5,
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		     31.0, 0.5);
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    cairo_stroke (cr);
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    cairo_translate (cr, 0, 2.0);
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    /* A reflected version: DBAC */
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3
    cairo_move_to (cr,
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		    19.5, 0.5);
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    cairo_curve_to (cr,
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		    18.5, 0.5,
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		    55.0, 0.5,
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		    -1.0, 0.5);
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    cairo_stroke (cr);
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    return CAIRO_TEST_SUCCESS;
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}
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CAIRO_TEST (curve_to_as_line_to,
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	    "Test optimization treating curve_to as line_to",
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	    "path", /* keywords */
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	    NULL, /* requirements */
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	    30,
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	    5,
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	    NULL, draw)