Changeset 148923 in webkit

Timestamp:

Apr 22, 2013 4:06:16 PM (11 years ago)

Author:

Martin Robinson

Message:

[Cairo] Canvas-shadow behavior is not being as expected
​https://bugs.webkit.org/show_bug.cgi?id=108897

Patch by Rashmi Shyamasundar <​rashmi.s2@samsung.com> on 2013-04-22
Reviewed by Martin Robinson.

Source/WebCore:

Use the pattern-extend-mode "CAIRO_EXTEND_NONE" instead of "CAIRO_EXTEND_PAD" in
PlatformContextCairo::drawSurfaceToContext().

In the function PlatformContextCairo::drawSurfaceToContext(), a pattern is being
created from the source surface and this pattern is drawn onto the destination
context. There is no gradient involved. Hence the extend mode for filling the
pattern should be "CAIRO_EXTEND_NONE". If we use the extend mode
"CAIRO_EXTEND_PAD" in PlatformContextCairo::drawSurfaceToContext(), the original
image area is also filled with the shadow color which is not the expected behavior.

Test: fast/canvas/canvas-image-shadow.html

• platform/graphics/cairo/PlatformContextCairo.cpp:

(WebCore::PlatformContextCairo::drawSurfaceToContext):

LayoutTests:

Test to verify the shadow of an image drawn on canvas.
This test uses an image whose size is smaller than,
the size of the rectangle which should be filled with the image.

• fast/canvas/canvas-image-shadow-expected.txt: Added.
• fast/canvas/canvas-image-shadow.html: Added.
• fast/canvas/green.png: Added.
• fast/canvas/script-tests/canvas-image-shadow.js: Added.

(draw):

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/canvas/script-tests/shadow-image.js (added)
• LayoutTests/fast/canvas/shadow-image-expected.txt (added)
• LayoutTests/fast/canvas/shadow-image.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/platform/graphics/cairo/PlatformContextCairo.cpp (modified) (1 diff)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2013-04-22  Rashmi Shyamasundar  <rashmi.s2@samsung.com>
+
+        [Cairo] Canvas-shadow behavior is not being as expected
+        https://bugs.webkit.org/show_bug.cgi?id=108897
+
+        Reviewed by Martin Robinson.
+
+        Test to verify the shadow of an image drawn on canvas. 
+        This test uses an image whose size is smaller than,
+        the size of the rectangle which should be filled with the image. 
+
+        * fast/canvas/canvas-image-shadow-expected.txt: Added.
+        * fast/canvas/canvas-image-shadow.html: Added.
+        * fast/canvas/green.png: Added.
+        * fast/canvas/script-tests/canvas-image-shadow.js: Added.
+        (draw):
+
 2013-04-22  Benjamin Poulain  <benjamin@webkit.org>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2013-04-22  Rashmi Shyamasundar  <rashmi.s2@samsung.com>
+
+        [Cairo] Canvas-shadow behavior is not being as expected
+        https://bugs.webkit.org/show_bug.cgi?id=108897
+
+        Reviewed by Martin Robinson.
+
+        Use the pattern-extend-mode "CAIRO_EXTEND_NONE" instead of "CAIRO_EXTEND_PAD" in
+        PlatformContextCairo::drawSurfaceToContext().
+
+        In the function PlatformContextCairo::drawSurfaceToContext(), a pattern is being
+        created from the source surface and this pattern is drawn onto the destination
+        context. There is no gradient involved. Hence the extend mode for filling the
+        pattern should be "CAIRO_EXTEND_NONE". If we use the extend mode
+        "CAIRO_EXTEND_PAD" in PlatformContextCairo::drawSurfaceToContext(), the original
+        image area is also filled with the shadow color which is not the expected behavior.
+
+        Test: fast/canvas/canvas-image-shadow.html
+
+        * platform/graphics/cairo/PlatformContextCairo.cpp:
+        (WebCore::PlatformContextCairo::drawSurfaceToContext):
+
 2013-04-22  Benjamin Poulain  <benjamin@webkit.org>
 

trunk/Source/WebCore/platform/graphics/cairo/PlatformContextCairo.cpp

@@ -192 +192 @@
         break;
     }
-    cairo_pattern_set_extend(pattern.get(), CAIRO_EXTEND_PAD);
+    cairo_pattern_set_extend(pattern.get(), CAIRO_EXTEND_NONE);
 
     // The pattern transformation properly scales the pattern for when the source rectangle is a