test: Add a1-mask-sample

Test sampling positions with a NEAREST mask.

test/Makefile.am

@@ -130,6 +130,7 @@ REFERENCE_IMAGES = \
 	a1-image-sample.ref.png \
 	a1-image-sample.gl.xfail.png \
 	a1-mask.ref.png \
+	a1-mask-sample.ref.png \
 	a1-traps-sample.ref.png \
 	a8-mask.ref.png \
 	alpha-similar.gl.argb32.xfail.png \

test/Makefile.sources

@@ -1,6 +1,7 @@
 test_sources = \
 	a1-image-sample.c 				\
 	a1-mask.c					\
+	a1-mask-sample.c 				\
 	a1-traps-sample.c				\
 	a8-mask.c					\
 	alpha-similar.c					\

test/a1-mask-sample.c

@@ -0,0 +1,83 @@
+/*
+ * Copyright © 2008 Red Hat, Inc.
+ * Copyright © 2010 Intel Corporation
+ *
+ * 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: Carl D. Worth <cworth@cworth.org>
+ *         Chris Wilson <chris@chris-wilson.co.uk>
+ */
+
+#include "cairo-test.h"
+
+#define POINTS	10
+#define STEP	(1.0 / POINTS)
+#define PAD	1
+#define WIDTH	(PAD + POINTS * 2 + PAD)
+#define HEIGHT	(WIDTH)
+
+/* A single, opaque pixel */
+static const uint32_t black_pixel = 0xffffffff;
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+    cairo_surface_t *surface;
+    cairo_pattern_t *mask;
+    int i, j;
+
+    surface = cairo_image_surface_create_for_data ((unsigned char *) &black_pixel,
+						   CAIRO_FORMAT_A8,
+						   1, 1, 4);
+    mask = cairo_pattern_create_for_surface (surface);
+    cairo_pattern_set_filter (mask, CAIRO_FILTER_NEAREST);
+    cairo_surface_destroy (surface);
+
+    /* Fill background white */
+    cairo_set_source_rgb (cr, 1, 1, 1);
+    cairo_paint (cr);
+
+    cairo_translate (cr, PAD, PAD);
+
+    cairo_set_source_rgb (cr, 0, 0, 0);
+    for (i = 0; i < POINTS; i++) {
+	for (j = 0; j < POINTS; j++) {
+	    cairo_matrix_t m;
+
+	    cairo_matrix_init_translate (&m,
+					 -(2 * i + i * STEP),
+					 -(2 * j + j * STEP));
+	    cairo_pattern_set_matrix (mask, &m);
+	    cairo_mask (cr, mask);
+	}
+    }
+
+    cairo_pattern_destroy (mask);
+
+    return CAIRO_TEST_SUCCESS;
+}
+
+CAIRO_TEST (a1_mask_sample,
+	    "Test sample position when masking with FILTER_NEAREST",
+	    "image, alpha", /* keywords */
+	    "target=raster", /* requirements */
+	    WIDTH, HEIGHT,
+	    NULL, draw)