Paint scrollbars at device scale resolution.

third_party/WebKit/Source/platform/exported/WebScrollbarThemePainter.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 23 matching lines @@
 #include "public/platform/WebRect.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 
 namespace blink {
 
 void WebScrollbarThemePainter::assign(const WebScrollbarThemePainter& painter)
 {
     // This is a pointer to a static object, so no ownership transferral.
     m_theme = painter.m_theme;
     m_scrollbar = painter.m_scrollbar;
+    m_deviceScaleFactor = painter.m_deviceScaleFactor;
 }
 
 void WebScrollbarThemePainter::reset()
 {
     m_scrollbar = nullptr;
 }
 
 void WebScrollbarThemePainter::paintScrollbarBackground(WebCanvas* canvas, const WebRect& rect)
 {
     SkRect clip = SkRect::MakeXYWH(rect.x, rect.y, rect.width, rect.height);
     canvas->clipRect(clip);
 
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);

[ccameron, 2015/11/06 23:15:20]

I have a vague preference for rolling this into SkPictureBuilder ctor, but that
involves lots of churn (probably not worth the bother).

     m_theme->paintScrollbarBackground(&pictureBuilder.context(), m_scrollbar.get());
     pictureBuilder.endRecording()->playback(canvas);
 }
 
 void WebScrollbarThemePainter::paintTrackBackground(WebCanvas* canvas, const WebRect& rect)
 {
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);
     m_theme->paintTrackBackground(&pictureBuilder.context(), m_scrollbar.get(), intRect);
     pictureBuilder.endRecording()->playback(canvas);
 }
 
 void WebScrollbarThemePainter::paintBackTrackPart(WebCanvas* canvas, const WebRect& rect)
 {
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);
     m_theme->paintTrackPiece(&pictureBuilder.context(), m_scrollbar.get(), intRect, BackTrackPart);
     pictureBuilder.endRecording()->playback(canvas);
 }
 
 void WebScrollbarThemePainter::paintForwardTrackPart(WebCanvas* canvas, const WebRect& rect)
 {
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);
     m_theme->paintTrackPiece(&pictureBuilder.context(), m_scrollbar.get(), intRect, ForwardTrackPart);
     pictureBuilder.endRecording()->playback(canvas);
 }
 
 void WebScrollbarThemePainter::paintBackButtonStart(WebCanvas* canvas, const WebRect& rect)
 {
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);
     m_theme->paintButton(&pictureBuilder.context(), m_scrollbar.get(), intRect, BackButtonStartPart);
     pictureBuilder.endRecording()->playback(canvas);
 }
 
 void WebScrollbarThemePainter::paintBackButtonEnd(WebCanvas* canvas, const WebRect& rect)
 {
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);
     m_theme->paintButton(&pictureBuilder.context(), m_scrollbar.get(), intRect, BackButtonEndPart);
     pictureBuilder.endRecording()->playback(canvas);
 }
 
 void WebScrollbarThemePainter::paintForwardButtonStart(WebCanvas* canvas, const WebRect& rect)
 {
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);
     m_theme->paintButton(&pictureBuilder.context(), m_scrollbar.get(), intRect, ForwardButtonStartPart);
     pictureBuilder.endRecording()->playback(canvas);
 }
 
 void WebScrollbarThemePainter::paintForwardButtonEnd(WebCanvas* canvas, const WebRect& rect)
 {
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);
     m_theme->paintButton(&pictureBuilder.context(), m_scrollbar.get(), intRect, ForwardButtonEndPart);
     pictureBuilder.endRecording()->playback(canvas);
 }
 
 void WebScrollbarThemePainter::paintTickmarks(WebCanvas* canvas, const WebRect& rect)
 {
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);
     m_theme->paintTickmarks(&pictureBuilder.context(), m_scrollbar.get(), intRect);
     pictureBuilder.endRecording()->playback(canvas);
 }
 
 void WebScrollbarThemePainter::paintThumb(WebCanvas* canvas, const WebRect& rect)
 {
     IntRect intRect(rect);
     SkPictureBuilder pictureBuilder(intRect);
+    pictureBuilder.context().setDeviceScaleFactor(m_deviceScaleFactor);
     m_theme->paintThumb(&pictureBuilder.context(), m_scrollbar.get(), intRect);
     pictureBuilder.endRecording()->playback(canvas);
 }
 
-WebScrollbarThemePainter::WebScrollbarThemePainter(ScrollbarTheme* theme, Scrollbar* scrollbar)
+WebScrollbarThemePainter::WebScrollbarThemePainter(ScrollbarTheme* theme, Scrollbar* scrollbar, float deviceScaleFactor)
     : m_theme(theme)
     , m_scrollbar(scrollbar)
+    , m_deviceScaleFactor(deviceScaleFactor)
 {
 }
 
 } // namespace blink