/* * Copyright 2011 Intel Corporation * * 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 * Chris Wilson not be used in advertising or publicity pertaining to * distribution of the software without specific, written prior * permission. Chris Wilson makes no representations about the * suitability of this software for any purpose. It is provided "as * is" without express or implied warranty. * * CHRIS WILSON DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND * FITNESS, IN NO EVENT SHALL CHRIS WILSON 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: Chris Wilson */ /* Exercises a bug spotted by Andrea Canciani where the polygon clipping * code was hopeless broken with horizontal edges. */ #include "cairo-test.h" #define WIDTH 16 #define HEIGHT 26 #define BUGY 1 #define BUGX (4 * BUGY * WIDTH * 256) static cairo_test_status_t draw (cairo_t *cr, int width, int height) { cairo_set_source_rgb (cr, 1, 1, 1); cairo_paint (cr); cairo_set_source_rgb (cr, 0, 0, 0); cairo_move_to (cr, - BUGX, 6 - BUGY); cairo_line_to (cr, + BUGX, 6 + BUGY); cairo_line_to (cr, WIDTH + BUGX, 2 - BUGY); cairo_line_to (cr, WIDTH - BUGX, 2 + BUGY); cairo_fill (cr); cairo_move_to (cr, WIDTH + BUGX, 8 - BUGY); cairo_line_to (cr, WIDTH - BUGX, 8 + BUGY); cairo_line_to (cr, - BUGX, 12 - BUGY); cairo_line_to (cr, + BUGX, 12 + BUGY); cairo_fill (cr); cairo_move_to (cr, - BUGX, 14 - BUGY); cairo_line_to (cr, + BUGX, 14 + BUGY); cairo_line_to (cr, WIDTH + BUGX, 18 - BUGY); cairo_line_to (cr, WIDTH - BUGX, 18 + BUGY); cairo_fill (cr); cairo_move_to (cr, WIDTH + BUGX, 24 - BUGY); cairo_line_to (cr, WIDTH - BUGX, 24 + BUGY); cairo_line_to (cr, - BUGX, 20 - BUGY); cairo_line_to (cr, + BUGX, 20 + BUGY); cairo_fill (cr); return CAIRO_TEST_SUCCESS; } CAIRO_TEST (horizontal_clip, "Tests intersection of a nearly horizontal lines with a clipped polygon", "clip, fill", /* keywords */ NULL, /* requirements */ WIDTH, HEIGHT, NULL, draw)