handle antialiased rendering as premultiplied

core/fxge/skia/fx_skia_device.cpp

 // Copyright 2014 PDFium 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 <algorithm>
 #include <utility>
 #include <vector>
 
 #include "core/fxcodec/fx_codec.h"
 #include "core/fxcrt/fx_memory.h"
@@ skipping 1157 matching lines @@
   glyphs.setCount(nChars);
   for (int index = 0; index < nChars; ++index) {
     const FXTEXT_CHARPOS& cp = pCharPos[index];
     positions[index] = {cp.m_OriginX * flip, cp.m_OriginY * vFlip};
     glyphs[index] = (uint16_t)cp.m_GlyphIndex;
   }
   m_pCanvas->drawPosText(glyphs.begin(), nChars * 2, positions.begin(), paint);
   m_pCanvas->restore();
 
 #ifdef _SKIA_SUPPORT_PATHS_
-  if (FXARGB_A(color) < 255) {
+  if (m_pBitmap->GetBPP() == 32) {
     m_pBitmap->MarkForUnPreMultiply(true);
   }
 #endif  // _SKIA_SUPPORT_PATHS_
   return true;
 }
 
 int CFX_SkiaDeviceDriver::GetDeviceCaps(int caps_id) const {
   switch (caps_id) {
     case FXDC_DEVICE_CLASS:
       return FXDC_DISPLAY;
@@ skipping 265 matching lines @@
   if (pGraphState && stroke_alpha) {
     DebugShowSkiaPath(skPath);
     DebugShowCanvasMatrix(m_pCanvas);
     DebugShowCanvasClip(m_pCanvas);
     skPaint.setStyle(SkPaint::kStroke_Style);
     skPaint.setColor(stroke_color);
     m_pCanvas->drawPath(skPath, skPaint);
   }
   m_pCanvas->restore();
 #ifdef _SKIA_SUPPORT_PATHS_
-  if ((fill_mode & 3 && FXARGB_A(fill_color) < 255) ||
-      (pGraphState && stroke_alpha < 255)) {
+  if (m_pBitmap->GetBPP() == 32) {
     m_pBitmap->MarkForUnPreMultiply(true);
   }
 #endif  // _SKIA_SUPPORT_PATHS_
   return true;
 }
 
 bool CFX_SkiaDeviceDriver::DrawCosmeticLine(FX_FLOAT x1,
                                             FX_FLOAT y1,
                                             FX_FLOAT x2,
                                             FX_FLOAT y2,
@@ skipping 383 matching lines @@
 #endif  // _SKIA_SUPPORT_
 
 #ifdef _SKIA_SUPPORT_PATHS_
   if (!m_pBitmap->GetBuffer()) {
     return true;
   }
   return static_cast<CFX_ImageRenderer*>(handle)->Continue(pPause);
 #endif  // _SKIA_SUPPORT_PATHS_
 }
 
-#ifdef _SKIA_SUPPORT_
+#if defined _SKIA_SUPPORT_
 void CFX_SkiaDeviceDriver::PreMultiply(CFX_DIBitmap* pDIBitmap) {
   void* buffer = pDIBitmap->GetBuffer();
   if (!buffer)
     return;
   if (pDIBitmap->GetBPP() != 32) {
     return;
   }
   int height = pDIBitmap->GetHeight();
   int width = pDIBitmap->GetWidth();
   int rowBytes = pDIBitmap->GetPitch();
   SkImageInfo unpremultipliedInfo =
       SkImageInfo::Make(width, height, kN32_SkColorType, kUnpremul_SkAlphaType);
   SkPixmap unpremultiplied(unpremultipliedInfo, buffer, rowBytes);
   SkImageInfo premultipliedInfo =
       SkImageInfo::Make(width, height, kN32_SkColorType, kPremul_SkAlphaType);
   SkPixmap premultiplied(premultipliedInfo, buffer, rowBytes);
   unpremultiplied.readPixels(premultiplied);
   pDIBitmap->DebugVerifyBitmapIsPreMultiplied();
 }
 #endif  // _SKIA_SUPPORT_
 
 #ifdef _SKIA_SUPPORT_PATHS_
 void CFX_SkiaDeviceDriver::UnPreMultiply(CFX_DIBitmap* pDIBitmap) {
-  if (!pDIBitmap->IsMarkedForUnPreMultiply())
+  pDIBitmap->UnPreMultiply();
+}
+
+void CFX_DIBitmap::UnPreMultiply() {
+  if (!this->IsMarkedForUnPreMultiply())

[dsinclair, 2016/11/21 22:01:49]

Drop the this-> as it isn't needed.

     return;
-  pDIBitmap->DebugVerifyBitmapIsPreMultiplied();
-  void* buffer = pDIBitmap->GetBuffer();
+  this->DebugVerifyBitmapIsPreMultiplied();
+  void* buffer = this->GetBuffer();
   if (!buffer)
     return;
-  if (pDIBitmap->GetBPP() != 32) {
+  if (this->GetBPP() != 32) {
     return;
   }
-  int height = pDIBitmap->GetHeight();
-  int width = pDIBitmap->GetWidth();
-  int rowBytes = pDIBitmap->GetPitch();
+  int height = this->GetHeight();
+  int width = this->GetWidth();
+  int rowBytes = this->GetPitch();
   SkImageInfo premultipliedInfo =
       SkImageInfo::Make(width, height, kN32_SkColorType, kPremul_SkAlphaType);
   SkPixmap premultiplied(premultipliedInfo, buffer, rowBytes);
   SkImageInfo unpremultipliedInfo =
       SkImageInfo::Make(width, height, kN32_SkColorType, kUnpremul_SkAlphaType);
   SkPixmap unpremultiplied(unpremultipliedInfo, buffer, rowBytes);
   premultiplied.readPixels(unpremultiplied);
-  pDIBitmap->MarkForUnPreMultiply(false);
+  this->MarkForUnPreMultiply(false);
 }
 #endif  // _SKIA_SUPPORT_PATHS_
 
 #ifdef _SKIA_SUPPORT_
 bool CFX_SkiaDeviceDriver::DrawBitsWithMask(const CFX_DIBSource* pSource,
                                             const CFX_DIBSource* pMask,
                                             int bitmap_alpha,
                                             const CFX_Matrix* pMatrix,
                                             int blend_type) {
   DebugValidate(m_pBitmap, m_pOriDevice);
@@ skipping 47 matching lines @@
                dest_top + pBitmap->GetHeight());
   return DrawBitsWithMask(pBitmap, pMask, bitmap_alpha, &m, blend_type);
 }
 
 void CFX_SkiaDeviceDriver::Clear(uint32_t color) {
   m_pCanvas->clear(color);
 }
 #endif  // _SKIA_SUPPORT_
 
 void CFX_SkiaDeviceDriver::Dump() const {
-#if SHOW_SKIA_PATH
+#if SHOW_SKIA_PATH && defined _SKIA_SUPPORT_
   if (m_pCache)
     m_pCache->Dump(this);
-#endif  // SHOW_SKIA_PATH
+#endif  // SHOW_SKIA_PATH && defined _SKIA_SUPPORT_
 }
 
 #ifdef _SKIA_SUPPORT_
 void CFX_SkiaDeviceDriver::DebugVerifyBitmapIsPreMultiplied() const {
   if (m_pOriDevice)
     m_pOriDevice->DebugVerifyBitmapIsPreMultiplied();
 }
 #endif  // _SKIA_SUPPORT_
 
 #ifdef _SKIA_SUPPORT_PATHS_
 void CFX_SkiaDeviceDriver::UnPreMultiplyDevice() {
-  UnPreMultiply(m_pBitmap);
+  if (!m_pBitmap->IsOffscreen())
+    UnPreMultiply(m_pBitmap);
 }
 #endif  // _SKIA_SUPPORT_PATHS_
 
 CFX_FxgeDevice::CFX_FxgeDevice() {
 #ifdef _SKIA_SUPPORT_
   m_bOwnedBitmap = false;
 #endif  // _SKIA_SUPPORT_
 }
 
 #ifdef _SKIA_SUPPORT_
@@ skipping 936 matching lines @@
       }
     }
     if (m_pDevice->GetBPP() == 1) {
       composite_span = &CFX_Renderer::CompositeSpan1bpp;
     }
     return true;
   }
 };
 
 #endif  // _SKIA_SUPPORT_PATHS_