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/*
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 * Copyright © 2026 Kevin Ushey
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 *
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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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 *
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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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 *
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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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 */
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#include "cairo-test.h"

            

        

            

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/* Test case for:

            

        

            

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 *

            

        

            

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 *      https://gitlab.freedesktop.org/cairo/cairo/-/issues/976

            

        

            

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 *

            

        

            

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 * With ANTIALIAS_NONE, abutting rectangles built with cairo_rectangle()

            

        

            

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 * could leave their shared pixel unpainted: the far edge was converted

            

        

            

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 * to fixed point as fixed(x) + fixed(width), which can differ from the

            

        

            

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 * abutting rectangle's fixed(x + width) by 1/256 and round to a

            

        

            

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 * different pixel.

            

        

            

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 *

            

        

            

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 * The cell size below is chosen so that the first cell's far edge lands

            

        

            

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 * exactly on a .5 fixed-point boundary (rounding down) while the next

            

        

            

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 * cell's origin rounds up, which used to leave a one-pixel white cross

            

        

            

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 * through the middle of the grid.

            

        

            

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 */

            

        

            

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static cairo_test_status_t

            

        

            

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draw (cairo_t *cr, int width, int height)

            

        

            

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{

            

        

            

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    double x0 = 1.7;

            

        

            

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    double size = 2.8024;

            

        

            

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    double x1 = x0 + size;

            

        

            

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                3
            

            

                
    cairo_set_source_rgb (cr, 1, 1, 1);

            

        

            

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    cairo_paint (cr);

            

        

            

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    cairo_set_antialias (cr, CAIRO_ANTIALIAS_NONE);

            

        

            

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    cairo_set_source_rgb (cr, 0, 0, 0);

            

        

            

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    /* this should draw a seamless 2x2 grid of cells */

            

        

            

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    cairo_rectangle (cr, x0, x0, size, size);

            

        

            

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    cairo_rectangle (cr, x1, x0, size, size);

            

        

            

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    cairo_rectangle (cr, x0, x1, size, size);

            

        

            

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    cairo_rectangle (cr, x1, x1, size, size);

            

        

            

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    cairo_fill (cr);

            

        

            

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    return CAIRO_TEST_SUCCESS;

            

        

            

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}

            

        

            

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CAIRO_TEST (bug_976,

            

        

            

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	    "Bug 976 (abutting rectangles can leave their shared pixel unpainted with ANTIALIAS_NONE)",

            

        

            

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	    "fill, antialias", /* keywords */

            

        

            

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	    "target=raster", /* requirements */

            

        

            

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	    10, 10,

            

        

            

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	    NULL, draw)