[test] Add a pass-through test.

Check that colour values are correctly passed through all the backends.
Simple test of the most fundamental functionality.

test/.gitignore

@@ -148,6 +148,7 @@ paint
 paint-repeat
 paint-source-alpha
 paint-with-alpha
+pass-through
 path-data
 pattern-get-type
 pattern-getters

test/Makefile.am

@@ -121,6 +121,7 @@ paint$(EXEEXT)						\
 paint-repeat$(EXEEXT)					\
 paint-source-alpha$(EXEEXT)				\
 paint-with-alpha$(EXEEXT)				\
+pass-through$(EXEEXT)					\
 pattern-get-type$(EXEEXT)				\
 pattern-getters$(EXEEXT)				\
 pixman-rotate$(EXEEXT)					\
@@ -732,6 +733,8 @@ REFERENCE_IMAGES = \
 	paint-with-alpha-svg11-ref.png	\
 	paint-source-alpha-pdf-ref.png \
 	paint-with-alpha-pdf-ref.png \
+	pass-through-ref.png \
+	pass-through-rgb24-ref.png \
 	pattern-getters-ref.png	\
 	pdf-surface-source-ref.png \
 	pixman-rotate-ref.png	\

test/pass-through.c

@@ -0,0 +1,99 @@
+/*
+ * 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
+ * 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"
+
+static cairo_test_draw_function_t draw;
+
+static const cairo_test_t test = {
+    "pass-through",
+    "Tests pixel values",
+    16, 256,
+    draw
+};
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+    int n;
+
+    for (n = 0; n < 256; n++) {
+	cairo_set_source_rgba (cr, 1, 1, 1, n / 255.);
+	cairo_rectangle (cr, 0, n, 2, 1);
+	cairo_fill (cr);
+    }
+    for (n = 0; n < 256; n++) {
+	cairo_set_source_rgb (cr, n / 255., n / 255., n / 255.);
+	cairo_rectangle (cr, 2, n, 2, 1);
+	cairo_fill (cr);
+    }
+
+    cairo_translate (cr, 4, 0);
+
+    for (n = 0; n < 256; n++) {
+	cairo_set_source_rgba (cr, 1, 0, 0, n / 255.);
+	cairo_rectangle (cr, 0, n, 2, 1);
+	cairo_fill (cr);
+    }
+    for (n = 0; n < 256; n++) {
+	cairo_set_source_rgb (cr, n / 255., 0, 0);
+	cairo_rectangle (cr, 2, n, 2, 1);
+	cairo_fill (cr);
+    }
+
+    cairo_translate (cr, 4, 0);
+
+    for (n = 0; n < 256; n++) {
+	cairo_set_source_rgba (cr, 0, 1, 0, n / 255.);
+	cairo_rectangle (cr, 0, n, 2, 1);
+	cairo_fill (cr);
+    }
+    for (n = 0; n < 256; n++) {
+	cairo_set_source_rgb (cr, 0, n / 255., 0);
+	cairo_rectangle (cr, 2, n, 2, 1);
+	cairo_fill (cr);
+    }
+
+    cairo_translate (cr, 4, 0);
+
+    for (n = 0; n < 256; n++) {
+	cairo_set_source_rgba (cr, 0, 0, 1, n / 255.);
+	cairo_rectangle (cr, 0, n, 2, 1);
+	cairo_fill (cr);
+    }
+    for (n = 0; n < 256; n++) {
+	cairo_set_source_rgb (cr, 0, 0, n / 255.);
+	cairo_rectangle (cr, 2, n, 2, 1);
+	cairo_fill (cr);
+    }
+
+    return CAIRO_TEST_SUCCESS;
+}
+
+int
+main (void)
+{
+    return cairo_test (&test);
+}