test: Add clip-intersect

Exercises a bug in the unbounded drawing of an empty polygon...

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

test/Makefile.refs

@@ -152,6 +152,7 @@ REFERENCE_IMAGES = \
 	clip-image.image16.ref.png \
 	clip-image.ps.ref.png \
 	clip-image.ref.png \
+	clip-intersect.ref.png \
 	clip-nesting.pdf.argb32.ref.png \
 	clip-nesting.ps.argb32.ref.png \
 	clip-nesting.ps.rgb24.ref.png \

test/Makefile.sources

@@ -42,6 +42,7 @@ test_sources = \
 	clip-fill-rule-pixel-aligned.c			\
 	clip-group-shapes.c				\
 	clip-image.c					\
+	clip-intersect.c				\
 	clip-nesting.c					\
 	clip-operator.c					\
 	clip-push-group.c				\

test/clip-intersect.c

@@ -0,0 +1,94 @@
+/*
+ * Copyright 2009 Chris Wilson
+ * 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 <chris@chris-wilson.co.uk>
+ */
+
+#include "cairo-test.h"
+
+#define WIDTH 20
+#define HEIGHT 20
+
+static void clip_mask (cairo_t *cr)
+{
+    cairo_move_to (cr, 10, 0);
+    cairo_line_to (cr, 0, 10);
+    cairo_line_to (cr, 10, 20);
+    cairo_line_to (cr, 20, 10);
+    cairo_clip (cr);
+}
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+    cairo_set_source_rgb (cr, 1, 1, 1);
+    cairo_paint (cr);
+
+    clip_mask (cr);
+    cairo_set_source_rgb (cr, 0, 1, 0);
+    cairo_paint (cr);
+    cairo_reset_clip (cr);
+
+    cairo_set_source_rgb (cr, 1, 0, 0);
+
+    cairo_rectangle (cr, 0, 0, 4, 4);
+    cairo_clip (cr);
+    clip_mask (cr);
+    cairo_paint (cr);
+    cairo_reset_clip (cr);
+
+    cairo_rectangle (cr, 20, 0, -4, 4);
+    cairo_clip (cr);
+    clip_mask (cr);
+    cairo_paint (cr);
+    cairo_reset_clip (cr);
+
+    cairo_rectangle (cr, 20, 20, -4, -4);
+    cairo_clip (cr);
+    clip_mask (cr);
+    cairo_paint (cr);
+    cairo_reset_clip (cr);
+
+    cairo_rectangle (cr, 0, 20, 4, -4);
+    cairo_clip (cr);
+    clip_mask (cr);
+    cairo_paint (cr);
+    cairo_reset_clip (cr);
+
+    cairo_set_source_rgb (cr, 0, 0, 1);
+
+    cairo_rectangle (cr, 8, 8, 4, 4);
+    cairo_clip (cr);
+    clip_mask (cr);
+    cairo_paint (cr);
+    cairo_reset_clip (cr);
+
+    return CAIRO_TEST_SUCCESS;
+}
+
+CAIRO_TEST (clip_intersect,
+	    "Tests intersection of a simple clip with a clip-mask",
+	    "clip, paint", /* keywords */
+	    NULL, /* requirements */
+	    WIDTH, HEIGHT,
+	    NULL, draw)