[cairo-commit] test/clip-fill-no-op.c test/clip-fill-no-op.ref.png test/clip-stroke-no-op.c test/clip-stroke-no-op.ref.png test/Makefile.am test/Makefile.sources

Chris Wilson ickle at kemper.freedesktop.org
Wed Nov 25 02:57:00 PST 2009


 test/Makefile.am               |    2 +
 test/Makefile.sources          |    2 +
 test/clip-fill-no-op.c         |   66 +++++++++++++++++++++++++++++++++++++++++
 test/clip-fill-no-op.ref.png   |binary
 test/clip-stroke-no-op.c       |   66 +++++++++++++++++++++++++++++++++++++++++
 test/clip-stroke-no-op.ref.png |binary
 6 files changed, 136 insertions(+)

New commits:
commit 0d8a04ef47426d87c7932f308a831e36b4ef7683
Author: Benjamin Otte <otte at gnome.org>
Date:   Wed Nov 25 10:48:39 2009 +0000

    test: Add cases to exercise clipping after no-ops
    
    Whilst investigating:
    
      Bug 31788: SVG <line> with y1 == y2 and both with fractional
                 part don't render
      https://bugs.webkit.org/show_bug.cgi?id=31788
    
    I found that it can be reduced to a no-op clip following a no-op stroke
    or fill. These conditions are exercised here and are shown to be a bug
    introduced in the 1.9.x development series.

diff --git a/test/Makefile.am b/test/Makefile.am
index 0e0593b..581c30b 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -175,6 +175,7 @@ REFERENCE_IMAGES = \
 	clip-fill.ps.xfail.png \
 	clip-fill.xlib.ref.png \
 	clip-fill.xlib-fallback.ref.png \
+	clip-fill-no-op.ref.png \
 	clip-fill-rule-pixel-aligned.ref.png \
 	clip-fill-rule-pixel-aligned.rgb24.ref.png \
 	clip-fill-rule.pdf.argb32.ref.png \
@@ -238,6 +239,7 @@ REFERENCE_IMAGES = \
 	clip-stroke.ref.png \
 	clip-stroke.xlib.ref.png \
 	clip-stroke.xlib-fallback.ref.png \
+	clip-stroke-no-op.ref.png \
 	clip-stroke-unbounded.argb32.ref.png \
 	clip-stroke-unbounded.rgb24.ref.png \
 	clip-stroke-unbounded.svg12.argb32.xfail.png \
diff --git a/test/Makefile.sources b/test/Makefile.sources
index 8dff25a..3b88056 100644
--- a/test/Makefile.sources
+++ b/test/Makefile.sources
@@ -18,6 +18,7 @@ test_sources = \
 	clip-device-offset.c				\
 	clip-empty.c					\
 	clip-fill.c					\
+	clip-fill-no-op.c				\
 	clip-fill-rule.c				\
 	clip-fill-rule-pixel-aligned.c			\
 	clip-fill-unbounded.c				\
@@ -26,6 +27,7 @@ test_sources = \
 	clip-operator.c					\
 	clip-push-group.c				\
 	clip-stroke.c					\
+	clip-stroke-no-op.c				\
 	clip-stroke-unbounded.c				\
 	clip-text.c					\
 	clip-twice.c					\
diff --git a/test/clip-fill-no-op.c b/test/clip-fill-no-op.c
new file mode 100644
index 0000000..dfc378f
--- /dev/null
+++ b/test/clip-fill-no-op.c
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2009 Benjamin Otte
+ *
+ * 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
+ * Benjamin Otte not be used in advertising or publicity pertaining to
+ * distribution of the software without specific, written prior
+ * permission. Benjamin Otte makes no representations about the
+ * suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * BENJAMIN OTTE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL BENJAMIN OTTE 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: Benjamin Otte <otte at gnome.org>
+ */
+
+#include "cairo-test.h"
+
+#define WIDTH 50
+#define HEIGHT 50
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+    /* Neutral gray background */
+    cairo_set_source_rgb (cr, 0.5, 0.5, 0.5);
+    cairo_paint (cr);
+
+    /* remove this clip operation and everything works */
+    cairo_rectangle (cr, 10, 10, 30, 30);
+    cairo_clip (cr);
+
+    /* remove this no-op and everything works */
+    cairo_fill (cr);
+
+    /* make the y coordinates integers and everything works */
+    cairo_move_to (cr, 20, 20.101562);
+    cairo_line_to (cr, 30, 20.101562);
+
+    /* This clip operation should fail to work. But with cairo 1.9, if all the 
+     * 3 cases above happen, the clip will not work and the paint will happen.
+     */
+    cairo_save (cr); {
+	cairo_set_source_rgba (cr, 1, 0.5, 0.5, 1);
+	cairo_clip_preserve (cr);
+	cairo_paint (cr);
+    } cairo_restore (cr);
+
+    return CAIRO_TEST_SUCCESS;
+}
+
+CAIRO_TEST (clip_fill_no_op,
+	    "Exercises a bug found by Benjamin Otte whereby a no-op clip is nullified by a stroke",
+	    "clip, fill", /* keywords */
+	    NULL, /* requirements */
+	    WIDTH, HEIGHT,
+	    NULL, draw)
diff --git a/test/clip-fill-no-op.ref.png b/test/clip-fill-no-op.ref.png
new file mode 100644
index 0000000..2256461
Binary files /dev/null and b/test/clip-fill-no-op.ref.png differ
diff --git a/test/clip-stroke-no-op.c b/test/clip-stroke-no-op.c
new file mode 100644
index 0000000..e727fc4
--- /dev/null
+++ b/test/clip-stroke-no-op.c
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2009 Benjamin Otte
+ *
+ * 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
+ * Benjamin Otte not be used in advertising or publicity pertaining to
+ * distribution of the software without specific, written prior
+ * permission. Benjamin Otte makes no representations about the
+ * suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * BENJAMIN OTTE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL BENJAMIN OTTE 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: Benjamin Otte <otte at gnome.org>
+ */
+
+#include "cairo-test.h"
+
+#define WIDTH 50
+#define HEIGHT 50
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+    /* Neutral gray background */
+    cairo_set_source_rgb (cr, 0.5, 0.5, 0.5);
+    cairo_paint (cr);
+
+    /* remove this clip operation and everything works */
+    cairo_rectangle (cr, 10, 10, 30, 30);
+    cairo_clip (cr);
+
+    /* remove this no-op and everything works */
+    cairo_stroke (cr);
+
+    /* make the y coordinates integers and everything works */
+    cairo_move_to (cr, 20, 20.101562);
+    cairo_line_to (cr, 30, 20.101562);
+
+    /* This clip operation should fail to work. But with cairo 1.9, if all the 
+     * 3 cases above happen, the clip will not work and the paint will happen.
+     */
+    cairo_save (cr); {
+	cairo_set_source_rgba (cr, 1, 0.5, 0.5, 1);
+	cairo_clip_preserve (cr);
+	cairo_paint (cr);
+    } cairo_restore (cr);
+
+    return CAIRO_TEST_SUCCESS;
+}
+
+CAIRO_TEST (clip_stroke_no_op,
+	    "Exercises a bug found by Benjamin Otte whereby a no-op clip is nullified by a stroke",
+	    "clip, stroke", /* keywords */
+	    NULL, /* requirements */
+	    WIDTH, HEIGHT,
+	    NULL, draw)
diff --git a/test/clip-stroke-no-op.ref.png b/test/clip-stroke-no-op.ref.png
new file mode 100644
index 0000000..2256461
Binary files /dev/null and b/test/clip-stroke-no-op.ref.png differ


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