Changeset 247846 in webkit

Timestamp:

Jul 25, 2019, 5:40:26 PM (7 years ago)

Author:

timothy_horton@apple.com

Message:

Subpixel fringes around TextIndicator snapshots at non-integral scale factors
​https://bugs.webkit.org/show_bug.cgi?id=200145

Reviewed by Simon Fraser.

• page/FrameSnapshotting.cpp:

(WebCore::snapshotFrameRectWithClip):

• page/FrameSnapshotting.h:
• page/TextIndicator.cpp:

(WebCore::snapshotOptionsForTextIndicatorOptions):
Round the scale factor up, and snappily enclose the clip rects.

TextIndicator doesn't require the use of the precise scale factor that
the page is painted at, but we want it to be sharp, so we overshoot!

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• page/FrameSnapshotting.cpp (modified) (2 diffs)
• page/FrameSnapshotting.h (modified) (1 diff)
• page/TextIndicator.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2019-07-25  Tim Horton  <timothy_horton@apple.com>
+
+        Subpixel fringes around TextIndicator snapshots at non-integral scale factors
+        https://bugs.webkit.org/show_bug.cgi?id=200145
+
+        Reviewed by Simon Fraser.
+
+        * page/FrameSnapshotting.cpp:
+        (WebCore::snapshotFrameRectWithClip):
+        * page/FrameSnapshotting.h:
+        * page/TextIndicator.cpp:
+        (WebCore::snapshotOptionsForTextIndicatorOptions):
+        Round the scale factor up, and snappily enclose the clip rects.
+
+        TextIndicator doesn't require the use of the precise scale factor that
+        the page is painted at, but we want it to be sharp, so we overshoot!
+
 2019-07-25  Brent Fulgham  <bfulgham@apple.com>
 

trunk/Source/WebCore/page/FrameSnapshotting.cpp

@@ -109 +109 @@
         scaleFactor *= frame.page()->pageScaleFactor();
 
+    if (options & SnapshotOptionsPaintWithIntegralScaleFactor)
+        scaleFactor = ceilf(scaleFactor);
+
     std::unique_ptr<ImageBuffer> buffer = ImageBuffer::create(imageRect.size(), Unaccelerated, scaleFactor);
     if (!buffer)
@@ -117 +120 @@
         Path clipPath;
         for (auto& rect : clipRects)
-            clipPath.addRect(rect);
+            clipPath.addRect(encloseRectToDevicePixels(rect, scaleFactor));
         buffer->context().clipPath(clipPath);
     }

trunk/Source/WebCore/page/FrameSnapshotting.h

@@ -48 +48 @@
     SnapshotOptionsForceBlackText = 1 << 3,
     SnapshotOptionsPaintSelectionAndBackgroundsOnly = 1 << 4,
-    SnapshotOptionsPaintEverythingExcludingSelection = 1 << 5
+    SnapshotOptionsPaintEverythingExcludingSelection = 1 << 5,
+    SnapshotOptionsPaintWithIntegralScaleFactor = 1 << 6,
 };
 typedef unsigned SnapshotOptions;

trunk/Source/WebCore/page/TextIndicator.cpp

@@ -133 +133 @@
 static SnapshotOptions snapshotOptionsForTextIndicatorOptions(TextIndicatorOptions options)
 {
-    SnapshotOptions snapshotOptions = SnapshotOptionsNone;
+    SnapshotOptions snapshotOptions = SnapshotOptionsPaintWithIntegralScaleFactor;
 
     if (!(options & TextIndicatorOptionPaintAllContent)) {