test: Add an loopy I-bar stroker test

A second relatively simple closed concave shape, all the better for
debugging with.

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

test/Makefile.refs

@@ -653,6 +653,7 @@ REFERENCE_IMAGES = \
 	inverse-text.ps.ref.png \
 	inverse-text.quartz.ref.png \
 	inverse-text.ref.png \
+	joins-loop.ref.png \
 	joins-star.ref.png \
 	joins.image16.ref.png \
 	joins.ps.ref.png \

test/Makefile.sources

@@ -146,6 +146,7 @@ test_sources = \
 	invalid-matrix.c				\
 	inverse-text.c					\
 	joins.c						\
+	joins-loop.c					\
 	joins-star.c					\
 	large-clip.c					\
 	large-font.c					\

test/joins-loop.c

@@ -0,0 +1,100 @@
+/*
+ * Copyright © 2011 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: Chris Wilson <chris@chris-wilson.co.uk>
+ */
+
+#include "cairo-test.h"
+
+#define LINE_WIDTH	10.
+#define SIZE		(8 * LINE_WIDTH)
+#define PAD		(1 * LINE_WIDTH)
+
+
+static void
+make_path (cairo_t *cr)
+{
+    cairo_move_to (cr, 0, 0);
+    cairo_rel_curve_to (cr,
+			SIZE, 0,
+			0, SIZE,
+			SIZE, SIZE);
+    cairo_rel_line_to (cr, -SIZE, 0);
+    cairo_rel_curve_to (cr,
+			SIZE, 0,
+			0, -SIZE,
+			SIZE, -SIZE);
+    cairo_close_path (cr);
+}
+
+static void
+draw_joins (cairo_t *cr)
+{
+    cairo_save (cr);
+    cairo_translate (cr, PAD, PAD);
+
+    make_path (cr);
+    cairo_set_line_join (cr, CAIRO_LINE_JOIN_BEVEL);
+    cairo_stroke (cr);
+    cairo_translate (cr, SIZE + PAD, 0.);
+
+    make_path (cr);
+    cairo_set_line_join (cr, CAIRO_LINE_JOIN_ROUND);
+    cairo_stroke (cr);
+    cairo_translate (cr, SIZE + PAD, 0.);
+
+    make_path (cr);
+    cairo_set_line_join (cr, CAIRO_LINE_JOIN_MITER);
+    cairo_stroke (cr);
+    cairo_translate (cr, SIZE + PAD, 0.);
+
+    cairo_restore (cr);
+}
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+    cairo_set_source_rgb (cr, 1.0, 1.0, 1.0);
+    cairo_paint (cr);
+
+    cairo_set_source_rgb (cr, 0.0, 0.0, 0.0);
+    cairo_set_line_width (cr, LINE_WIDTH);
+
+    draw_joins (cr);
+
+    /* and reflect to generate the opposite vertex ordering */
+    cairo_translate (cr, 0, height);
+    cairo_scale (cr, 1, -1);
+
+    draw_joins (cr);
+
+    return CAIRO_TEST_SUCCESS;
+}
+
+CAIRO_TEST (joins_loop,
+	    "A loopy concave shape",
+	    "stroke", /* keywords */
+	    NULL, /* requirements */
+	    3*(SIZE+PAD)+PAD, 2*(SIZE+PAD)+2*PAD,
+	    NULL, draw)
+