Grcov report - degenerate-pen.c

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/*

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 * Copyright © 2007 Red Hat, Inc.

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 * Permission is hereby granted, free of charge, to any person

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 * obtaining a copy of this software and associated documentation

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 * files (the "Software"), to deal in the Software without

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 * restriction, including without limitation the rights to use, copy,

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 * modify, merge, publish, distribute, sublicense, and/or sell copies

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 * of the Software, and to permit persons to whom the Software is

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 * furnished to do so, subject to the following conditions:

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 * The above copyright notice and this permission notice shall be

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 * included in all copies or substantial portions of the Software.

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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

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 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

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 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

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 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS

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 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN

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 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

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 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

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 * SOFTWARE.

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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   20

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#define PAD    5

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#define WIDTH  (PAD + 3 * (PAD + SIZE) + PAD)

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#define HEIGHT (PAD + SIZE + PAD)

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/* We're demonstrating here a bug originally reported by Benjamin Otte

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 * on the cairo mailing list here, (after he ran into this problem

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 * with various flash animations):

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 *	[cairo] Assertion `i < pen->num_vertices' failed in 1.4.10

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 *	https://lists.cairographics.org/archives/cairo/2007-August/011282.html

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 * The problem shows up with an extreme transformation matrix that

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 * collapses the pen to a single line, (which means that

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 * _cairo_slope_compare cannot handle adjacent vertices in the pen

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 * since they have parallel slope).

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 * This test case tests degenerate pens in several directions and uses

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 * round caps to force the stroking code to attempt to walk around the

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 * pen doing slope comparisons.

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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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3

    cairo_set_source_rgb (cr, 1, 1, 1);

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3

    cairo_paint (cr);

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3

    cairo_set_source_rgb (cr, 0, 0, 0);

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3

    cairo_set_line_join (cr, CAIRO_LINE_JOIN_ROUND);

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    cairo_translate (cr, PAD, PAD);

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    /* First compress the pen to a vertical line. */

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3

    cairo_rectangle (cr, 0, 0, SIZE, SIZE);

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3

    cairo_curve_to (cr, SIZE / 2, 0, SIZE, SIZE / 2, SIZE, SIZE);

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3

    cairo_save (cr);

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3

	cairo_scale (cr, 0.000001, 1.0);

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3

	cairo_stroke (cr);

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3

    cairo_restore (cr);

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3

    cairo_translate (cr, PAD + SIZE, 0);

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    /* Then compress the pen to a horizontal line. */

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3

    cairo_rectangle (cr, 0, 0, SIZE, SIZE);

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3

    cairo_curve_to (cr, SIZE / 2, 0, SIZE, SIZE / 2, SIZE, SIZE);

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3

    cairo_save (cr);

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3

	cairo_scale (cr, 1.0, 0.000001);

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3

	cairo_stroke (cr);

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3

    cairo_restore (cr);

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    cairo_translate (cr, PAD + SIZE, 0);

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    /* Finally a line at an angle. */

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3

    cairo_rectangle (cr, 0, 0, SIZE, SIZE);

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3

    cairo_curve_to (cr, SIZE / 2, 0, SIZE, SIZE / 2, SIZE, SIZE);

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3

    cairo_save (cr);

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3

	cairo_rotate (cr, M_PI / 4.0);

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3

	cairo_scale (cr, 0.000001, 1.0);

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3

	cairo_stroke (cr);

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    cairo_restore (cr);

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3

    return CAIRO_TEST_SUCCESS;

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CAIRO_TEST (degenerate_pen,

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	    "Test round joins with a pen that's transformed to a line",

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	    "degenerate", /* keywords */

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	    NULL, /* requirements */

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	    WIDTH, HEIGHT,

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	    NULL, draw)