[test] Add gradient-constant-alpha.

PostScript can handle alpha gradients, iff they have a constant alpha. So
exercise that path.

2 files changed, 76 insertions, 0 deletions

diff --git a/test/Makefile.am b/test/Makefile.am
index 562f4d49..0ded81d0 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -66,6 +66,7 @@ get-clip$(EXEEXT)					\
 get-group-target$(EXEEXT)				\
 get-path-extents$(EXEEXT)				\
 gradient-alpha$(EXEEXT)					\
+gradient-constant-alpha$(EXEEXT)			\
 gradient-zero-stops$(EXEEXT)				\
 group-paint$(EXEEXT)					\
 image-surface-source$(EXEEXT)				\
@@ -452,6 +453,12 @@ REFERENCE_IMAGES = \
 	gradient-alpha-ps-rgb24-ref.png	\
 	gradient-alpha-ref.png	\
 	gradient-alpha-rgb24-ref.png	\
+	gradient-constant-alpha-pdf-argb32-ref.png	\
+	gradient-constant-alpha-pdf-rgb24-ref.png	\
+	gradient-constant-alpha-ps-argb32-ref.png	\
+	gradient-constant-alpha-ps-rgb24-ref.png	\
+	gradient-constant-alpha-ref.png	\
+	gradient-constant-alpha-rgb24-ref.png	\
 	gradient-zero-stops-ref.png	\
 	gradient-zero-stops-rgb24-ref.png	\
 	group-paint-ref.png	\
diff --git a/test/gradient-constant-alpha.c b/test/gradient-constant-alpha.c
new file mode 100644
index 00000000..0607621e
--- /dev/null
+++ b/test/gradient-constant-alpha.c
@@ -0,0 +1,69 @@
+/*
+ * Copyright © 2005 Red Hat, Inc.
+ * Copyright © 2008 Chris Wilson
+ *
+ * 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
+ * Red Hat, Inc. not be used in advertising or publicity pertaining to
+ * distribution of the software without specific, written prior
+ * permission. Red Hat, Inc. makes no representations about the
+ * suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * RED HAT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL RED HAT, INC. 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: Carl D. Worth <cworth@cworth.org>
+ *         Chris Wilson <chris@chris-wilson.co.uk>
+ */
+
+#include "cairo-test.h"
+
+static cairo_test_draw_function_t draw;
+
+static const cairo_test_t test = {
+    "gradient-constant-alpha",
+    "Tests drawing of a gradient with constant alpha values in the color stops\n",
+    10, 10,
+    draw
+};
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+    cairo_pattern_t *gradient;
+
+    gradient = cairo_pattern_create_linear (0, 0,
+					    0, height);
+    cairo_pattern_add_color_stop_rgba (gradient, 0.0,
+				       1.0, 0.0, 0.0,
+				       0.5);
+    cairo_pattern_add_color_stop_rgba (gradient, 0.0,
+				       0.0, 1.0, 0.0,
+				       0.5);
+    cairo_pattern_add_color_stop_rgba (gradient, 1.0,
+				       0.0, 0.0, 1.0,
+				       0.5);
+
+    cairo_set_source (cr, gradient);
+
+    cairo_paint (cr);
+
+    cairo_pattern_destroy (gradient);
+
+    return CAIRO_TEST_SUCCESS;
+}
+
+int
+main (void)
+{
+    return cairo_test (&test);
+}