image/SurfacePipe.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "SurfacePipe.h"
   8
   9 #include <algorithm>  // for min
  10
  11 #include "Decoder.h"
  12
  13 namespace mozilla {
  14 namespace image {
  15
  16 using namespace gfx;
  17
  18 using std::min;
  19
  20 Maybe<SurfaceInvalidRect> AbstractSurfaceSink::TakeInvalidRect() {
  21   if (mInvalidRect.IsEmpty()) {
  22     return Nothing();
  23   }
  24
  25   SurfaceInvalidRect invalidRect;
  26   invalidRect.mInputSpaceRect = invalidRect.mOutputSpaceRect = mInvalidRect;
  27
  28   // Forget about the invalid rect we're returning.
  29   mInvalidRect = IntRect();
  30
  31   return Some(invalidRect);
  32 }
  33
  34 uint8_t* AbstractSurfaceSink::DoResetToFirstRow() {
  35   mRow = 0;
  36   return GetRowPointer();
  37 }
  38
  39 uint8_t* AbstractSurfaceSink::DoAdvanceRowFromBuffer(const uint8_t* aInputRow) {
  40   CopyInputRow(aInputRow);
  41   return DoAdvanceRow();
  42 }
  43
  44 uint8_t* AbstractSurfaceSink::DoAdvanceRow() {
  45   if (mRow >= uint32_t(InputSize().height)) {
  46     return nullptr;
  47   }
  48
  49   // If we're vertically flipping the output, we need to flip the invalid rect.
  50   // Since we're dealing with an axis-aligned rect, only the y coordinate needs
  51   // to change.
  52   int32_t invalidY = mFlipVertically ? InputSize().height - (mRow + 1) : mRow;
  53   mInvalidRect.UnionRect(mInvalidRect,
  54                          IntRect(0, invalidY, InputSize().width, 1));
  55
  56   mRow = min(uint32_t(InputSize().height), mRow + 1);
  57
  58   return mRow < uint32_t(InputSize().height) ? GetRowPointer() : nullptr;
  59 }
  60
  61 nsresult SurfaceSink::Configure(const SurfaceConfig& aConfig) {
  62   IntSize surfaceSize = aConfig.mOutputSize;
  63
  64   // Allocate the frame.
  65   // XXX(seth): Once every Decoder subclass uses SurfacePipe, we probably want
  66   // to allocate the frame directly here and get rid of Decoder::AllocateFrame
  67   // altogether.
  68   nsresult rv = aConfig.mDecoder->AllocateFrame(surfaceSize, aConfig.mFormat,
  69                                                 aConfig.mAnimParams);
  70   if (NS_FAILED(rv)) {
  71     return rv;
  72   }
  73
  74   mImageData = aConfig.mDecoder->mImageData;
  75   mImageDataLength = aConfig.mDecoder->mImageDataLength;
  76   mFlipVertically = aConfig.mFlipVertically;
  77
  78   MOZ_ASSERT(mImageData);
  79   MOZ_ASSERT(uint64_t(mImageDataLength) == uint64_t(surfaceSize.width) *
  80                                                uint64_t(surfaceSize.height) *
  81                                                sizeof(uint32_t));
  82
  83   ConfigureFilter(surfaceSize, sizeof(uint32_t));
  84   return NS_OK;
  85 }
  86
  87 uint8_t* SurfaceSink::GetRowPointer() const {
  88   // If we're flipping vertically, reverse the order in which we traverse the
  89   // rows.
  90   uint32_t row = mFlipVertically ? InputSize().height - (mRow + 1) : mRow;
  91
  92   uint8_t* rowPtr = mImageData + row * InputSize().width * sizeof(uint32_t);
  93
  94   MOZ_ASSERT(rowPtr >= mImageData);
  95   MOZ_ASSERT(rowPtr < mImageData + mImageDataLength);
  96   MOZ_ASSERT(rowPtr + InputSize().width * sizeof(uint32_t) <=
  97              mImageData + mImageDataLength);
  98
  99   return rowPtr;
 100 }
 101
 102 }  // namespace image
 103 }  // namespace mozilla