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