Changeset 246350 in webkit

Timestamp:

Jun 12, 2019 6:43:37 AM (5 years ago)

Author:

Carlos Garcia Campos

Message:

[cairo][SVG] Putting multiple path elements in clippath causes rendering artifacts
​https://bugs.webkit.org/show_bug.cgi?id=198701
<rdar://problem/51620347>

Reviewed by Don Olmstead.

Source/WebCore:

We need to save the current transformation matrix at the moment the image mask is set and set it again on
restore right before applying the mask. This patch also creates a pattern for the image mask surface and set its
transformation matrix according to the mask position, so that we don't need to save the mask rectangle too.

Tests: svg/clip-path/clip-hidpi-expected.svg

svg/clip-path/clip-hidpi.svg
svg/clip-path/clip-opacity-translate-expected.svg
svg/clip-path/clip-opacity-translate.svg

• platform/graphics/cairo/PlatformContextCairo.cpp:

(WebCore::PlatformContextCairo::restore):
(WebCore::PlatformContextCairo::pushImageMask):

LayoutTests:

• svg/clip-path/clip-hidpi-expected.svg: Added.
• svg/clip-path/clip-hidpi.svg: Added.
• svg/clip-path/clip-opacity-translate-expected.svg: Added.
• svg/clip-path/clip-opacity-translate.svg: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/svg/clip-path/clip-hidpi-expected.svg (added)
• LayoutTests/svg/clip-path/clip-hidpi.svg (added)
• LayoutTests/svg/clip-path/clip-opacity-translate-expected.svg (added)
• LayoutTests/svg/clip-path/clip-opacity-translate.svg (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/platform/graphics/cairo/PlatformContextCairo.cpp (modified) (4 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2019-06-12  Carlos Garcia Campos  <cgarcia@igalia.com>
+
+        [cairo][SVG] Putting multiple path elements in clippath causes rendering artifacts
+        https://bugs.webkit.org/show_bug.cgi?id=198701
+        <rdar://problem/51620347>
+
+        Reviewed by Don Olmstead.
+
+        * svg/clip-path/clip-hidpi-expected.svg: Added.
+        * svg/clip-path/clip-hidpi.svg: Added.
+        * svg/clip-path/clip-opacity-translate-expected.svg: Added.
+        * svg/clip-path/clip-opacity-translate.svg: Added.
+
 2019-06-12  Fujii Hironori  <Hironori.Fujii@sony.com>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2019-06-12  Carlos Garcia Campos  <cgarcia@igalia.com>
+
+        [cairo][SVG] Putting multiple path elements in clippath causes rendering artifacts
+        https://bugs.webkit.org/show_bug.cgi?id=198701
+        <rdar://problem/51620347>
+
+        Reviewed by Don Olmstead.
+
+        We need to save the current transformation matrix at the moment the image mask is set and set it again on
+        restore right before applying the mask. This patch also creates a pattern for the image mask surface and set its
+        transformation matrix according to the mask position, so that we don't need to save the mask rectangle too.
+
+        Tests: svg/clip-path/clip-hidpi-expected.svg
+               svg/clip-path/clip-hidpi.svg
+               svg/clip-path/clip-opacity-translate-expected.svg
+               svg/clip-path/clip-opacity-translate.svg
+
+        * platform/graphics/cairo/PlatformContextCairo.cpp:
+        (WebCore::PlatformContextCairo::restore):
+        (WebCore::PlatformContextCairo::pushImageMask):
+
 2019-06-11  Wenson Hsieh  <wenson_hsieh@apple.com>
 

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

@@ -31 +31 @@
 #if USE(CAIRO)
 
-#include "CairoUtilities.h"
-#include "Gradient.h"
-#include "GraphicsContext.h"
-#include "Pattern.h"
 #include <cairo.h>
 
 namespace WebCore {
-
-// In Cairo image masking is immediate, so to emulate image clipping we must save masking
-// details as part of the context state and apply them during platform restore.
-class ImageMaskInformation {
-public:
-    void update(cairo_surface_t* maskSurface, const FloatRect& maskRect)
-    {
-        m_maskSurface = maskSurface;
-        m_maskRect = maskRect;
-    }
-
-    bool isValid() const { return m_maskSurface; }
-    cairo_surface_t* maskSurface() const { return m_maskSurface.get(); }
-    const FloatRect& maskRect() const { return m_maskRect; }
-
-private:
-    RefPtr<cairo_surface_t> m_maskSurface;
-    FloatRect m_maskRect;
-};
-
 
 // Encapsulates the additional painting state information we store for each
@@ -65 +41 @@
     State() = default;
 
-    ImageMaskInformation m_imageMaskInformation;
+    struct {
+        RefPtr<cairo_pattern_t> pattern;
+        cairo_matrix_t matrix;
+    } m_mask;
 };
 
@@ -77 +56 @@
 void PlatformContextCairo::restore()
 {
-    const ImageMaskInformation& maskInformation = m_state->m_imageMaskInformation;
-    if (maskInformation.isValid()) {
-        const FloatRect& maskRect = maskInformation.maskRect();
+    if (m_state->m_mask.pattern) {
         cairo_pop_group_to_source(m_cr.get());
-        cairo_mask_surface(m_cr.get(), maskInformation.maskSurface(), maskRect.x(), maskRect.y());
+
+        cairo_matrix_t matrix;
+        cairo_get_matrix(m_cr.get(), &matrix);
+        cairo_set_matrix(m_cr.get(), &m_state->m_mask.matrix);
+        cairo_mask(m_cr.get(), m_state->m_mask.pattern.get());
+        cairo_set_matrix(m_cr.get(), &matrix);
     }
 
@@ -106 +88 @@
     // since we actually apply the mask in restorePlatformState.
     ASSERT(!m_stateStack.isEmpty());
-    m_state->m_imageMaskInformation.update(surface, rect);
+    m_state->m_mask.pattern = adoptRef(cairo_pattern_create_for_surface(surface));
+    cairo_get_matrix(m_cr.get(), &m_state->m_mask.matrix);
 
-    // Cairo doesn't support the notion of an image clip, so we push a group here
-    // and then paint it to the surface with an image mask (which is an immediate
-    // operation) during restorePlatformState.
+    cairo_matrix_t matrix;
+    cairo_matrix_init_translate(&matrix, -rect.x(), -rect.y());
+    cairo_pattern_set_matrix(m_state->m_mask.pattern.get(), &matrix);
+
     cairo_push_group(m_cr.get());
 }