Limit manual control of platform painting

skia/ext/bitmap_platform_device_win.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <windows.h>
 #include <psapi.h>
 #include <stddef.h>
 
 #include "base/debug/gdi_debug_util_win.h"
 #include "base/logging.h"
@@ skipping 182 matching lines @@
 BitmapPlatformDevice::BitmapPlatformDevice(
     HBITMAP hbitmap,
     const SkBitmap& bitmap)
     : SkBitmapDevice(bitmap),
       hbitmap_(hbitmap),
       old_hbitmap_(NULL),
       hdc_(NULL),
       config_dirty_(true),  // Want to load the config next time.
       transform_(SkMatrix::I()) {
   // The data object is already ref'ed for us by create().
-  SkDEBUGCODE(begin_paint_count_ = 0);
   if (hbitmap) {
     SetPlatformDevice(this, this);
     // Initialize the clip region to the entire bitmap.
     BITMAP bitmap_data;
     if (GetObject(hbitmap_, sizeof(BITMAP), &bitmap_data)) {
       SkIRect rect;
       rect.set(0, 0, bitmap_data.bmWidth, bitmap_data.bmHeight);
       clip_region_ = SkRegion(rect);
     }
   }
 }
 
 BitmapPlatformDevice::~BitmapPlatformDevice() {
-  SkASSERT(begin_paint_count_ == 0);
   if (hdc_)
     ReleaseBitmapDC();
 }
 
 HDC BitmapPlatformDevice::BeginPlatformPaint() {
-  SkDEBUGCODE(begin_paint_count_++);
   return GetBitmapDC();
 }
 
-void BitmapPlatformDevice::EndPlatformPaint() {
-  SkASSERT(begin_paint_count_--);
-  PlatformDevice::EndPlatformPaint();
-}
-
 void BitmapPlatformDevice::setMatrixClip(const SkMatrix& transform,
                                          const SkRegion& region,
                                          const SkClipStack&) {
   SetMatrixClip(transform, region);
 }
 
 void BitmapPlatformDevice::DrawToHDC(HDC dc, int x, int y,
                                      const RECT* src_rect) {
   bool created_dc = !IsBitmapDCCreated();
   HDC source_dc = BeginPlatformPaint();

[f(malita), 2016/03/29 17:31:07]

Nit: use ScopedPlatformPaint here also?

[tomhudson, 2016/03/29 17:47:31]

No; we're calling this->BeginPlatformPaint(), not
skia::BeginPlatformPaint(SkCanvas*).

 
   RECT temp_rect;
   if (!src_rect) {
     temp_rect.left = 0;
     temp_rect.right = width();
     temp_rect.top = 0;
     temp_rect.bottom = height();
     src_rect = &temp_rect;
   }
 
@@ skipping 26 matching lines @@
                   copy_height,
                   source_dc,
                   src_rect->left,
                   src_rect->top,
                   copy_width,
                   copy_height,
                   blend_function);
   }
   LoadTransformToDC(source_dc, transform_);
 
-  EndPlatformPaint();
   if (created_dc)
     ReleaseBitmapDC();
 }
 
 const SkBitmap& BitmapPlatformDevice::onAccessBitmap() {
   // FIXME(brettw) OPTIMIZATION: We should only flush if we know a GDI
   // operation has occurred on our DC.
   if (IsBitmapDCCreated())
     GdiFlush();
   return SkBitmapDevice::onAccessBitmap();
@@ skipping 13 matching lines @@
                                int height,
                                bool is_opaque,
                                HANDLE shared_section,
                                OnFailureType failureType) {
   skia::RefPtr<SkBaseDevice> dev = skia::AdoptRef(
       BitmapPlatformDevice::Create(width, height, is_opaque, shared_section));
   return CreateCanvas(dev, failureType);
 }
 
 }  // namespace skia