fix rotated and alpha bitmaps

Match the matrix supplied by PDFium to the one expected
by Skia to draw bitmaps.

Set up the color if the bitmap is an image mask.

Additional work required to figure out when bitmap
filtering should be applied.

R=reed@google.com,dsinclair@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2004203003

1 files changed, 15 insertions, 20 deletions

diff --git a/core/fxge/skia/fx_skia_device.cpp b/core/fxge/skia/fx_skia_device.cpp
index 177f10c5b9..0edb73acb8 100644
--- a/core/fxge/skia/fx_skia_device.cpp
+++ b/core/fxge/skia/fx_skia_device.cpp
@@ -15,6 +15,7 @@
 #include "core/fxge/skia/fx_skia_device.h"
 
 #include "third_party/skia/include/core/SkCanvas.h"
+#include "third_party/skia/include/core/SkColorFilter.h"
 #include "third_party/skia/include/core/SkColorPriv.h"
 #include "third_party/skia/include/core/SkPaint.h"
 #include "third_party/skia/include/core/SkPath.h"
@@ -1012,8 +1013,6 @@ FX_BOOL CFX_SkiaDeviceDriver::StartDIBits(const CFX_DIBSource* pSource,
   int rowBytes = pSource->GetPitch();
   switch (pSource->GetBPP()) {
     case 1: {
-      uint8_t zero = pSource->IsAlphaMask() ? 0xFF : 0x00;
-      uint8_t one = zero ^ 0xFF;
       dst8Storage.reset(FX_Alloc2D(uint8_t, width, height));
       uint8_t* dst8Pixels = dst8Storage.get();
       for (int y = 0; y < height; ++y) {
@@ -1021,11 +1020,12 @@ FX_BOOL CFX_SkiaDeviceDriver::StartDIBits(const CFX_DIBSource* pSource,
             static_cast<const uint8_t*>(buffer) + y * rowBytes;
         uint8_t* dstRow = dst8Pixels + y * width;
         for (int x = 0; x < width; ++x)
-          dstRow[x] = srcRow[x >> 3] & (1 << (~x & 0x07)) ? one : zero;
+          dstRow[x] = srcRow[x >> 3] & (1 << (~x & 0x07)) ? 0xFF : 0x00;
       }
       buffer = dst8Storage.get();
       rowBytes = width;
-      colorType = SkColorType::kGray_8_SkColorType;
+      colorType = pSource->IsAlphaMask() ? SkColorType::kAlpha_8_SkColorType
+                                         : SkColorType::kGray_8_SkColorType;
     } break;
     case 8:
       colorType = SkColorType::kGray_8_SkColorType;
@@ -1051,31 +1051,26 @@ FX_BOOL CFX_SkiaDeviceDriver::StartDIBits(const CFX_DIBSource* pSource,
     default:
       colorType = SkColorType::kUnknown_SkColorType;
   }
-  SkImageInfo imageInfo =
-      SkImageInfo::Make(width, height, colorType, kOpaque_SkAlphaType);
+  SkImageInfo imageInfo = SkImageInfo::Make(
+      width, height, colorType,
+      pSource->IsAlphaMask() ? kPremul_SkAlphaType : kOpaque_SkAlphaType);
   SkBitmap skBitmap;
   skBitmap.installPixels(imageInfo, buffer, rowBytes,
                          nullptr, /* TODO(caryclark) : set color table */
                          nullptr, nullptr);
   m_pCanvas->save();
-  bool landscape = !pMatrix->a;
-  if (landscape)
-    m_pCanvas->translate(m_pCanvas->imageInfo().width(), 0);
-  else
-    m_pCanvas->translate(pMatrix->e, pMatrix->f + pMatrix->d);
-
-  SkMatrix skMatrix = SkMatrix::MakeScale(1.f / width, 1.f / height);
-  m_pCanvas->concat(skMatrix);
+  SkMatrix skMatrix;
   const CFX_Matrix& m = *pMatrix;
-  // note that PDF's y-axis goes up; Skia's y-axis goes down
-  if (landscape)
-    skMatrix.setAll(-m.a, -m.b, m.e, m.c, m.d, m.f, 0, 0, 1);
-  else
-    skMatrix.setAll(m.a, m.b, 0, -m.c, -m.d, 0, 0, 0, 1);
+  skMatrix.setAll(m.a / width, -m.c / height, m.c + m.e, m.b / width,
+                  -m.d / height, m.d + m.f, 0, 0, 1);
   m_pCanvas->concat(skMatrix);
   SkPaint paint;
   paint.setAntiAlias(true);
-  paint.setFilterQuality(kHigh_SkFilterQuality);
+  if (pSource->IsAlphaMask()) {
+    paint.setColorFilter(
+        SkColorFilter::MakeModeFilter(argb, SkXfermode::kSrc_Mode));
+  }
+  // paint.setFilterQuality(kHigh_SkFilterQuality);
   paint.setXfermodeMode(GetSkiaBlendMode(blend_type));
   paint.setAlpha(bitmap_alpha);
   m_pCanvas->drawBitmap(skBitmap, 0, 0, &paint);