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+/*
+ * Copyright © 2006 M Joonas Pihlaja
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Author: M Joonas Pihlaja <jpihlaja@cc.helsinki.fi>
+ */
+
+/* Bug history
+ *
+ * 2006-12-05 M Joonas Pihlaja <jpihlaja@cc.helsinki.fi>
+ *
+ * The cairo_in_fill () function can sometimes produce false
+ * positives when the tessellator produces empty trapezoids
+ * and the query point lands exactly on a trapezoid edge.
+ */
+
+#include "cairo-test.h"
+
+static cairo_test_status_t
+preamble (cairo_test_context_t *ctx)
+{
+ int x,y;
+ int width = 10;
+ int height = 10;
+ cairo_surface_t *surf;
+ cairo_t *cr;
+ int false_positive_count = 0;
+ cairo_status_t status;
+ cairo_test_status_t ret;
+
+ surf = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, width, height);
+ cr = cairo_create (surf);
+ cairo_surface_destroy (surf);
+
+ /* Empty horizontal trapezoid. */
+ cairo_move_to (cr, 0, height/3);
+ cairo_line_to (cr, width, height/3);
+ cairo_close_path (cr);
+
+ /* Empty non-horizontal trapezoid #1. */
+ cairo_move_to (cr, 0, 0);
+ cairo_line_to (cr, width, height/2);
+ cairo_close_path (cr);
+
+ /* Empty non-horizontal trapezoid #2 intersecting #1. */
+ cairo_move_to (cr, 0, height/2);
+ cairo_line_to (cr, width, 0);
+ cairo_close_path (cr);
+
+ status = cairo_status (cr);
+
+ /* Point sample the tessellated path. */
+ for (y = 0; y < height; y++) {
+ for (x = 0; x < width; x++) {
+ if (cairo_in_fill (cr, x, y)) {
+ false_positive_count++;
+ }
+ }
+ }
+ cairo_destroy (cr);
+
+ /* Check that everything went well. */
+ ret = CAIRO_TEST_SUCCESS;
+ if (CAIRO_STATUS_SUCCESS != status) {
+ cairo_test_log (ctx, "Failed to create a test surface and path: %s\n",
+ cairo_status_to_string (status));
+ ret = CAIRO_TEST_XFAILURE;
+ }
+
+ if (0 != false_positive_count) {
+ cairo_test_log (ctx, "Point sampling found %d false positives "
+ "from cairo_in_fill()\n",
+ false_positive_count);
+ ret = CAIRO_TEST_XFAILURE;
+ }
+
+ return ret;
+}
+
+/*
+ * XFAIL: The cairo_in_fill () function can sometimes produce false positives
+ * when the tessellator produces empty trapezoids and the query point lands
+ * exactly on a trapezoid edge.
+ */
+CAIRO_TEST (in_fill_empty_trapezoid,
+ "Test that the tessellator isn't producing obviously empty trapezoids",
+ "in, trap", /* keywords */
+ NULL, /* requirements */
+ 0, 0,
+ preamble, NULL)