copy graphics state fully

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.
 
 #if defined(_SKIA_SUPPORT_)
 #include <algorithm>
 #include <vector>
 
 #include "core/fxcodec/include/fx_codec.h"
 
@@ skipping 68 matching lines @@
 #else  // DRAW_SKIA_CLIP
 
 void DebugDrawSkiaClipRect(SkCanvas* canvas, const SkRect& rect) {}
 void DebugDrawSkiaClipPath(SkCanvas* canvas, const SkPath& path) {}
 
 #endif  // DRAW_SKIA_CLIP
 
 #undef SHOW_SKIA_PATH
 #undef DRAW_SKIA_CLIP
 
-static void DebugVerifyBitmapIsPreMultiplied(void* buffer,
-                                             int width,
-                                             int height) {
-#ifdef SK_DEBUG
-  // verify that input is really premultiplied
-  for (int y = 0; y < height; ++y) {
-    const uint32_t* srcRow = static_cast<const uint32_t*>(buffer) + y * width;
-    for (int x = 0; x < width; ++x) {
-      uint8_t a = SkGetPackedA32(srcRow[x]);
-      uint8_t r = SkGetPackedR32(srcRow[x]);
-      uint8_t g = SkGetPackedG32(srcRow[x]);
-      uint8_t b = SkGetPackedB32(srcRow[x]);
-      SkA32Assert(a);
-      SkASSERT(r <= a);
-      SkASSERT(g <= a);
-      SkASSERT(b <= a);
-    }
-  }
-#endif
-}
-
 static void DebugValidate(const CFX_DIBitmap* bitmap,
                           const CFX_DIBitmap* device) {
   if (bitmap) {
     SkASSERT(bitmap->GetBPP() == 8 || bitmap->GetBPP() == 32);
     if (bitmap->GetBPP() == 32) {
-      DebugVerifyBitmapIsPreMultiplied(bitmap->GetBuffer(), bitmap->GetWidth(),
-                                       bitmap->GetHeight());
+      bitmap->DebugVerifyBitmapIsPreMultiplied();
     }
   }
   if (device) {
     SkASSERT(device->GetBPP() == 8 || device->GetBPP() == 32);
     if (device->GetBPP() == 32) {
-      DebugVerifyBitmapIsPreMultiplied(device->GetBuffer(), device->GetWidth(),
-                                       device->GetHeight());
+      device->DebugVerifyBitmapIsPreMultiplied();
     }
   }
 }
 
 SkPath BuildPath(const CFX_PathData* pPathData) {
   SkPath skPath;
   const CFX_PathData* pFPath = pPathData;
   int nPoints = pFPath->GetPointCount();
   FX_PATHPOINT* pPoints = pFPath->GetPoints();
   for (int i = 0; i < nPoints; i++) {
@@ skipping 150 matching lines @@
       return false;
     FX_FLOAT boundsEnd =
         i < inputs - 1 ? pFunc->GetBound(i) : pFunc->GetDomain(1);
     skPos->push(boundsStart);
     skPos->push(boundsEnd);
     boundsStart = boundsEnd;
   }
   return true;
 }
 
-void RgbByteOrderTransferBitmap(CFX_DIBitmap* pBitmap,
-                                int dest_left,
-                                int dest_top,
-                                int width,
-                                int height,
-                                const CFX_DIBSource* pSrcBitmap,
-                                int src_left,
-                                int src_top) {
-  if (!pBitmap)
-    return;
-  pBitmap->GetOverlapRect(dest_left, dest_top, width, height,
-                          pSrcBitmap->GetWidth(), pSrcBitmap->GetHeight(),
-                          src_left, src_top, nullptr);
-  if (width == 0 || height == 0)
-    return;
-  int Bpp = pBitmap->GetBPP() / 8;
-  FXDIB_Format dest_format = pBitmap->GetFormat();
-  FXDIB_Format src_format = pSrcBitmap->GetFormat();
-  int pitch = pBitmap->GetPitch();
-  uint8_t* buffer = pBitmap->GetBuffer();
-  if (dest_format == src_format) {
-    for (int row = 0; row < height; row++) {
-      uint8_t* dest_scan = buffer + (dest_top + row) * pitch + dest_left * Bpp;
-      uint8_t* src_scan =
-          (uint8_t*)pSrcBitmap->GetScanline(src_top + row) + src_left * Bpp;
-      if (Bpp == 4) {
-        for (int col = 0; col < width; col++) {
-          FXARGB_SETDIB(dest_scan, FXARGB_MAKE(src_scan[3], src_scan[0],
-                                               src_scan[1], src_scan[2]));
-          dest_scan += 4;
-          src_scan += 4;
-        }
-      } else {
-        for (int col = 0; col < width; col++) {
-          *dest_scan++ = src_scan[2];
-          *dest_scan++ = src_scan[1];
-          *dest_scan++ = src_scan[0];
-          src_scan += 3;
-        }
-      }
-    }
-    return;
-  }
-  uint8_t* dest_buf = buffer + dest_top * pitch + dest_left * Bpp;
-  if (dest_format == FXDIB_Rgb) {
-    if (src_format == FXDIB_Rgb32) {
-      for (int row = 0; row < height; row++) {
-        uint8_t* dest_scan = dest_buf + row * pitch;
-        uint8_t* src_scan =
-            (uint8_t*)pSrcBitmap->GetScanline(src_top + row) + src_left * 4;
-        for (int col = 0; col < width; col++) {
-          *dest_scan++ = src_scan[2];
-          *dest_scan++ = src_scan[1];
-          *dest_scan++ = src_scan[0];
-          src_scan += 4;
-        }
-      }
-    } else {
-      ASSERT(FALSE);
-    }
-  } else if (dest_format == FXDIB_Argb || dest_format == FXDIB_Rgb32) {
-    if (src_format == FXDIB_Rgb) {
-      for (int row = 0; row < height; row++) {
-        uint8_t* dest_scan = (uint8_t*)(dest_buf + row * pitch);
-        uint8_t* src_scan =
-            (uint8_t*)pSrcBitmap->GetScanline(src_top + row) + src_left * 3;
-        for (int col = 0; col < width; col++) {
-          FXARGB_SETDIB(dest_scan, FXARGB_MAKE(0xff, src_scan[0], src_scan[1],
-                                               src_scan[2]));
-          dest_scan += 4;
-          src_scan += 3;
-        }
-      }
-    } else if (src_format == FXDIB_Rgb32) {
-      ASSERT(dest_format == FXDIB_Argb);
-      for (int row = 0; row < height; row++) {
-        uint8_t* dest_scan = dest_buf + row * pitch;
-        uint8_t* src_scan =
-            (uint8_t*)(pSrcBitmap->GetScanline(src_top + row) + src_left * 4);
-        for (int col = 0; col < width; col++) {
-          FXARGB_SETDIB(dest_scan, FXARGB_MAKE(0xff, src_scan[0], src_scan[1],
-                                               src_scan[2]));
-          src_scan += 4;
-          dest_scan += 4;
-        }
-      }
-    }
-  } else {
-    ASSERT(FALSE);
-  }
-}
-
 // see https://en.wikipedia.org/wiki/Distance_from_a_point_to_a_line
 SkScalar LineSide(const SkPoint line[2], const SkPoint& pt) {
   return (line[1].fY - line[0].fY) * pt.fX - (line[1].fX - line[0].fX) * pt.fY +
          line[1].fX * line[0].fY - line[1].fY * line[0].fX;
 }
 
 SkPoint IntersectSides(const SkPoint& parallelPt,
                        const SkVector& paraRay,
                        const SkPoint& perpendicularPt) {
   SkVector perpRay = {paraRay.fY, -paraRay.fX};
@@ skipping 122 matching lines @@
     if (m_drawPath && DrawChanged(pMatrix, pDrawState, fill_color, stroke_color,
                                   fill_mode, blend_type)) {
       FlushPath(pDriver);
     }
     if (!m_drawPath) {
       m_skPath.reset();
       m_fillPath = (fill_mode & 3) && fill_color;
       m_skPath.setFillType((fill_mode & 3) == FXFILL_ALTERNATE
                                ? SkPath::kEvenOdd_FillType
                                : SkPath::kWinding_FillType);
-      m_drawState = *pDrawState;
+      if (pDrawState)
+        m_drawState.Copy(*pDrawState);
       m_fillColor = fill_color;
       m_strokeColor = stroke_color;
       m_blendType = blend_type;
-      m_drawMatrix = *pMatrix;
+      if (pMatrix)
+        m_drawMatrix = *pMatrix;
     }
     SkPath skPath = BuildPath(pPathData);
     SkPoint delta;
     if (MatrixOffset(pMatrix, &delta))
       skPath.offset(delta.fX, delta.fY);
     m_skPath.addPath(skPath);
     m_drawPath = true;
     return true;
   }
 
@@ skipping 83 matching lines @@
     SkPaint skPaint;
     skPaint.setAntiAlias(true);
     skPaint.setColor(m_fillColor);
     if (m_pFont->GetFace() && m_pCache) {  // exclude placeholder test fonts
       sk_sp<SkTypeface> typeface(SkSafeRef(m_pCache->GetDeviceCache(m_pFont)));
       skPaint.setTypeface(typeface);
     }
     skPaint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
     skPaint.setTextSize(m_fontSize);
     skPaint.setSubpixelText(true);
+    skPaint.setHinting(SkPaint::kNo_Hinting);
     SkCanvas* skCanvas = pDriver->SkiaCanvas();
     skCanvas->save();
     skCanvas->concat(skMatrix);
     skCanvas->drawPosText(m_glyphs.begin(), m_glyphs.count() * 2,
                           m_positions.begin(), skPaint);
     skCanvas->restore();
     m_drawText = false;
   }
 
   bool SetClipFill(const CFX_PathData* pPathData,
@@ skipping 37 matching lines @@
     SkMatrix skMatrix = ToSkMatrix(*pMatrix);
     SkPaint skPaint;
     pDriver->PaintStroke(&skPaint, pGraphState, skMatrix);
     SkPath dst_path;
     skPaint.getFillPath(skPath, &dst_path);
     dst_path.transform(skMatrix);
     return SetClip(dst_path, pDriver);
   }
 
   bool MatrixOffset(const CFX_Matrix* pMatrix, SkPoint* delta) {
+    CFX_Matrix identityMatrix;
+    if (!pMatrix)
+      pMatrix = &identityMatrix;
     delta->set(pMatrix->e - m_drawMatrix.e, pMatrix->f - m_drawMatrix.f);
     if (!delta->fX && !delta->fY)
       return true;
     SkMatrix drawMatrix = ToSkMatrix(m_drawMatrix);
     if (!(drawMatrix.getType() & ~SkMatrix::kTranslate_Mask))
       return true;
     SkMatrix invDrawMatrix;
     if (!drawMatrix.invert(&invDrawMatrix))
       return false;
     SkMatrix invNewMatrix;
@@ skipping 79 matching lines @@
                    CFX_FontCache* pCache,
                    const CFX_Matrix* pMatrix,
                    FX_FLOAT font_size,
                    uint32_t color) {
     return pFont != m_pFont || pCache != m_pCache ||
            MatrixChanged(pMatrix, m_drawMatrix) || font_size != m_fontSize ||
            color != m_fillColor;
   }
 
   bool MatrixChanged(const CFX_Matrix* pMatrix, const CFX_Matrix& refMatrix) {
+    CFX_Matrix identityMatrix;
+    if (!pMatrix)
+      pMatrix = &identityMatrix;
     return pMatrix->a != refMatrix.a || pMatrix->b != refMatrix.b ||
            pMatrix->c != refMatrix.c || pMatrix->d != refMatrix.d;
   }
 
   bool StateChanged(const CFX_GraphStateData* pState,
                     const CFX_GraphStateData& refState) {
+    CFX_GraphStateData identityState;
+    if (!pState)
+      pState = &identityState;
     return pState->m_LineWidth != refState.m_LineWidth ||
            pState->m_LineCap != refState.m_LineCap ||
            pState->m_LineJoin != refState.m_LineJoin ||
            pState->m_MiterLimit != refState.m_MiterLimit ||
            DashChanged(pState, refState);
   }
 
   bool DashChanged(const CFX_GraphStateData* pState,
                    const CFX_GraphStateData& refState) {
-    if (!pState->m_DashArray && !refState.m_DashArray)
+    bool dashArray = pState && pState->m_DashArray;
+    if (!dashArray && !refState.m_DashArray)
       return false;
-    if (!pState->m_DashArray || !refState.m_DashArray)
+    if (!dashArray || !refState.m_DashArray)
       return true;
     if (pState->m_DashPhase != refState.m_DashPhase ||
         pState->m_DashCount != refState.m_DashCount) {
       return true;
     }
     for (int index = 0; index < pState->m_DashCount; ++index) {
       if (pState->m_DashArray[index] != refState.m_DashArray[index])
         return false;
     }
     return true;
@@ skipping 119 matching lines @@
 }
 
 CFX_SkiaDeviceDriver::CFX_SkiaDeviceDriver(CFX_DIBitmap* pBitmap,
                                            FX_BOOL bRgbByteOrder,
                                            CFX_DIBitmap* pOriDevice,
                                            FX_BOOL bGroupKnockout)
     : m_pBitmap(pBitmap),
       m_pOriDevice(pOriDevice),
       m_pRecorder(nullptr),
       m_pCache(new SkiaState),
-      m_bRgbByteOrder(bRgbByteOrder),
       m_bGroupKnockout(bGroupKnockout) {
   SkBitmap skBitmap;
   SkASSERT(pBitmap->GetBPP() == 8 || pBitmap->GetBPP() == 32);
   SkImageInfo imageInfo = SkImageInfo::Make(
       pBitmap->GetWidth(), pBitmap->GetHeight(),
       pBitmap->GetBPP() == 8 ? kAlpha_8_SkColorType : kN32_SkColorType,
       kOpaque_SkAlphaType);
   skBitmap.installPixels(imageInfo, pBitmap->GetBuffer(), pBitmap->GetPitch(),
                          nullptr, /* to do : set color table */
                          nullptr, nullptr);
   m_pCanvas = new SkCanvas(skBitmap);
   if (m_bGroupKnockout)
     SkDebugf("");  // FIXME(caryclark) suppress 'm_bGroupKnockout is unused'
 }
 
 CFX_SkiaDeviceDriver::CFX_SkiaDeviceDriver(int size_x, int size_y)
     : m_pBitmap(nullptr),
       m_pOriDevice(nullptr),
       m_pRecorder(new SkPictureRecorder),
       m_pCache(new SkiaState),
-      m_bRgbByteOrder(FALSE),
       m_bGroupKnockout(FALSE) {
   m_pRecorder->beginRecording(SkIntToScalar(size_x), SkIntToScalar(size_y));
   m_pCanvas = m_pRecorder->getRecordingCanvas();
 }
 
 CFX_SkiaDeviceDriver::CFX_SkiaDeviceDriver(SkPictureRecorder* recorder)
     : m_pBitmap(nullptr),
       m_pOriDevice(nullptr),
       m_pRecorder(recorder),
       m_pCache(new SkiaState),
-      m_bRgbByteOrder(FALSE),
       m_bGroupKnockout(FALSE) {
   m_pCanvas = m_pRecorder->getRecordingCanvas();
 }
 
 CFX_SkiaDeviceDriver::~CFX_SkiaDeviceDriver() {
   Flush();
   if (!m_pRecorder)
     delete m_pCanvas;
 }
 
@@ skipping 13 matching lines @@
                          font_size, color, this)) {
     return TRUE;
   }
   sk_sp<SkTypeface> typeface(
       SkSafeRef(pCache ? pCache->GetDeviceCache(pFont) : nullptr));
   SkPaint paint;
   paint.setAntiAlias(true);
   paint.setColor(color);
   paint.setTypeface(typeface);
   paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
+  paint.setHinting(SkPaint::kNo_Hinting);
   paint.setTextSize(font_size);
   paint.setSubpixelText(true);
   m_pCanvas->save();
   SkMatrix skMatrix = ToFlippedSkMatrix(*pObject2Device);
   m_pCanvas->concat(skMatrix);
   SkTDArray<SkPoint> positions;
   positions.setCount(nChars);
   SkTDArray<uint16_t> glyphs;
   glyphs.setCount(nChars);
   for (int index = 0; index < nChars; ++index) {
@@ skipping 322 matching lines @@
   pRect->top = 0;
   const SkImageInfo& canvasSize = m_pCanvas->imageInfo();
   pRect->right = canvasSize.width();
   pRect->bottom = canvasSize.height();
   return TRUE;
 }
 
 FX_BOOL CFX_SkiaDeviceDriver::GetDIBits(CFX_DIBitmap* pBitmap,
                                         int left,
                                         int top) {
-  if (!m_pBitmap || !m_pBitmap->GetBuffer())
+  if (!m_pBitmap)
     return TRUE;
-
-  FX_RECT rect(left, top, left + pBitmap->GetWidth(),
-               top + pBitmap->GetHeight());
-  std::unique_ptr<CFX_DIBitmap> pBack;
-  if (m_pOriDevice) {
-    pBack.reset(m_pOriDevice->Clone(&rect));
-    if (!pBack)
-      return TRUE;
-
-    pBack->CompositeBitmap(0, 0, pBack->GetWidth(), pBack->GetHeight(),
-                           m_pBitmap, 0, 0);
-  } else {
-    pBack.reset(m_pBitmap->Clone(&rect));
-    if (!pBack)
-      return TRUE;
-  }
-
-  left = std::min(left, 0);
-  top = std::min(top, 0);
-  if (m_bRgbByteOrder) {
-    RgbByteOrderTransferBitmap(pBitmap, 0, 0, rect.Width(), rect.Height(),
-                               pBack.get(), left, top);
+  uint8_t* srcBuffer = m_pBitmap->GetBuffer();
+  if (!srcBuffer)
     return TRUE;
-  }
-
-  return pBitmap->TransferBitmap(0, 0, rect.Width(), rect.Height(), pBack.get(),
-                                 left, top);
+  int srcWidth = m_pBitmap->GetWidth();
+  int srcHeight = m_pBitmap->GetHeight();
+  int srcRowBytes = srcWidth * sizeof(uint32_t);
+  SkImageInfo srcImageInfo = SkImageInfo::Make(
+      srcWidth, srcHeight, SkColorType::kN32_SkColorType, kPremul_SkAlphaType);
+  SkBitmap skSrcBitmap;
+  skSrcBitmap.installPixels(srcImageInfo, srcBuffer, srcRowBytes, nullptr,
+                            nullptr, nullptr);
+  SkASSERT(pBitmap);
+  uint8_t* dstBuffer = pBitmap->GetBuffer();
+  SkASSERT(dstBuffer);
+  int dstWidth = pBitmap->GetWidth();
+  int dstHeight = pBitmap->GetHeight();
+  int dstRowBytes = dstWidth * sizeof(uint32_t);
+  SkImageInfo dstImageInfo = SkImageInfo::Make(
+      dstWidth, dstHeight, SkColorType::kN32_SkColorType, kPremul_SkAlphaType);
+  SkBitmap skDstBitmap;
+  skDstBitmap.installPixels(dstImageInfo, dstBuffer, dstRowBytes, nullptr,
+                            nullptr, nullptr);
+  SkCanvas canvas(skDstBitmap);
+  canvas.drawBitmap(skSrcBitmap, left, top, nullptr);
+  return TRUE;
 }
 
 CFX_DIBitmap* CFX_SkiaDeviceDriver::GetBackDrop() {
   return m_pOriDevice;
 }
 
 FX_BOOL CFX_SkiaDeviceDriver::SetDIBits(const CFX_DIBSource* pBitmap,
                                         uint32_t argb,
                                         const FX_RECT* pSrcRect,
                                         int left,
@@ skipping 88 matching lines @@
         }
       }
       buffer = dst32Storage.get();
       rowBytes = width * sizeof(uint32_t);
       colorType = SkColorType::kN32_SkColorType;
       alphaType = kOpaque_SkAlphaType;
     } break;
     case 32:
       colorType = SkColorType::kN32_SkColorType;
       alphaType = kPremul_SkAlphaType;
-      DebugVerifyBitmapIsPreMultiplied(buffer, width, height);
+      pSource->DebugVerifyBitmapIsPreMultiplied(buffer);
       break;
     default:
       SkASSERT(0);  // TODO(caryclark) ensure that all cases are covered
       colorType = SkColorType::kUnknown_SkColorType;
   }
   SkImageInfo imageInfo =
       SkImageInfo::Make(width, height, colorType, alphaType);
   SkBitmap skBitmap;
   skBitmap.installPixels(imageInfo, buffer, rowBytes, ct, nullptr, nullptr);
   m_pCanvas->save();
@@ skipping 16 matching lines @@
   if (ct)
     ct->unref();
   DebugValidate(m_pBitmap, m_pOriDevice);
   return TRUE;
 }
 
 FX_BOOL CFX_SkiaDeviceDriver::ContinueDIBits(void* handle, IFX_Pause* pPause) {
   return FALSE;
 }
 
-void CFX_SkiaDeviceDriver::PreMultiply() {
-  PreMultiply(m_pBitmap);
-}
-
 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);
-  DebugVerifyBitmapIsPreMultiplied(buffer, width, height);
+  pDIBitmap->DebugVerifyBitmapIsPreMultiplied();
 }
 
 void CFX_SkiaDeviceDriver::Dump() const {
 #ifdef SK_DEBUG
   if (m_pCache)
     m_pCache->Dump(this);
 #endif
 }
 
+void CFX_SkiaDeviceDriver::DebugVerifyBitmapIsPreMultiplied() const {
+  if (m_pOriDevice)
+    m_pOriDevice->DebugVerifyBitmapIsPreMultiplied();
+}
+
 CFX_FxgeDevice::CFX_FxgeDevice() {
   m_bOwnedBitmap = FALSE;
 }
 
 SkPictureRecorder* CFX_FxgeDevice::CreateRecorder(int size_x, int size_y) {
   CFX_SkiaDeviceDriver* skDriver = new CFX_SkiaDeviceDriver(size_x, size_y);
   SetDeviceDriver(skDriver);
   return skDriver->GetRecorder();
 }
 
@@ skipping 27 matching lines @@
     return false;
   }
   SetBitmap(pBitmap);
   CFX_SkiaDeviceDriver* pDriver =
       new CFX_SkiaDeviceDriver(pBitmap, FALSE, pOriDevice, FALSE);
   SetDeviceDriver(pDriver);
   return true;
 }
 
 CFX_FxgeDevice::~CFX_FxgeDevice() {
+  Flush();
+  // call destructor of CFX_RenderDevice / CFX_SkiaDeviceDriver immediately
   if (m_bOwnedBitmap && GetBitmap())
     delete GetBitmap();
 }
 
-void CFX_FxgeDevice::PreMultiply() {
-  (static_cast<CFX_SkiaDeviceDriver*>(GetDeviceDriver()))->PreMultiply();
+void CFX_FxgeDevice::DebugVerifyBitmapIsPreMultiplied() const {
+#ifdef SK_DEBUG
+  CFX_SkiaDeviceDriver* skDriver =
+      static_cast<CFX_SkiaDeviceDriver*>(GetDeviceDriver());
+  if (skDriver)
+    skDriver->DebugVerifyBitmapIsPreMultiplied();
+#endif
+}
+
+void CFX_DIBSource::DebugVerifyBitmapIsPreMultiplied(void* opt) const {
+#ifdef SK_DEBUG
+  SkASSERT(32 == GetBPP());
+  const uint32_t* buffer = (const uint32_t*)(opt ? opt : GetBuffer());
+  int width = GetWidth();
+  int height = GetHeight();
+  // verify that input is really premultiplied
+  for (int y = 0; y < height; ++y) {
+    const uint32_t* srcRow = buffer + y * width;
+    for (int x = 0; x < width; ++x) {
+      uint8_t a = SkGetPackedA32(srcRow[x]);
+      uint8_t r = SkGetPackedR32(srcRow[x]);
+      uint8_t g = SkGetPackedG32(srcRow[x]);
+      uint8_t b = SkGetPackedB32(srcRow[x]);
+      SkA32Assert(a);
+      SkASSERT(r <= a);
+      SkASSERT(g <= a);
+      SkASSERT(b <= a);
+    }
+  }
+#endif
 }
 
 #endif