The Tor Browser: image/src/FrameBlender.cpp@6474c204b198 (annotated)

image/src/FrameBlender.cpp@6474c204b198 (annotated)

image/src/FrameBlender.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include "FrameBlender.h"
 #include "mozilla/MemoryReporting.h"
 #include "MainThreadUtils.h"
 #include "pixman.h"
 using namespace mozilla;
 using namespace mozilla::image;
 namespace mozilla {
 namespace image {
 FrameBlender::FrameBlender(FrameSequence* aSequenceToUse /* = nullptr */)
  : mFrames(aSequenceToUse)
  , mAnim(nullptr)
  , mLoopCount(-1)
 {
   if (!mFrames) {
     mFrames = new FrameSequence();
   }
 }
 FrameBlender::~FrameBlender()
 {
   delete mAnim;
 }
 already_AddRefed<FrameSequence>
 FrameBlender::GetFrameSequence()
 {
   nsRefPtr<FrameSequence> seq(mFrames);
   return seq.forget();
 }
 imgFrame*
 FrameBlender::GetFrame(uint32_t framenum) const
 {
   if (!mAnim) {
     NS_ASSERTION(framenum == 0, "Don't ask for a frame > 0 if we're not animated!");
     return mFrames->GetFrame(0);
   }
   if (mAnim->lastCompositedFrameIndex == int32_t(framenum))
     return mAnim->compositingFrame;
   return mFrames->GetFrame(framenum);
 }
 imgFrame*
 FrameBlender::RawGetFrame(uint32_t framenum) const
 {
   if (!mAnim) {
     NS_ASSERTION(framenum == 0, "Don't ask for a frame > 0 if we're not animated!");
     return mFrames->GetFrame(0);
   }
   return mFrames->GetFrame(framenum);
 }
 uint32_t
 FrameBlender::GetNumFrames() const
 {
   return mFrames->GetNumFrames();
 }
 int32_t
 FrameBlender::GetTimeoutForFrame(uint32_t framenum) const
 {
   const int32_t timeout = RawGetFrame(framenum)->GetRawTimeout();
   // Ensure a minimal time between updates so we don't throttle the UI thread.
   // consider 0 == unspecified and make it fast but not too fast.  Unless we have
   // a single loop GIF. See bug 890743, bug 125137, bug 139677, and bug 207059.
   // The behavior of recent IE and Opera versions seems to be:
   // IE 6/Win:
   //   10 - 50ms go 100ms
   //   >50ms go correct speed
   // Opera 7 final/Win:
   //   10ms goes 100ms
   //   >10ms go correct speed
   // It seems that there are broken tools out there that set a 0ms or 10ms
   // timeout when they really want a "default" one.  So munge values in that
   // range.
   if (timeout >= 0 && timeout <= 10 && mLoopCount != 0)
     return 100;
   return timeout;
 }
 void
 FrameBlender::SetLoopCount(int32_t aLoopCount)
 {
   mLoopCount = aLoopCount;
 }
 int32_t
 FrameBlender::GetLoopCount() const
 {
   return mLoopCount;
 }
 void
 FrameBlender::RemoveFrame(uint32_t framenum)
 {
   NS_ABORT_IF_FALSE(framenum < GetNumFrames(), "Deleting invalid frame!");
   mFrames->RemoveFrame(framenum);
 }
 void
 FrameBlender::ClearFrames()
 {
   // Forget our old frame sequence, letting whoever else has it deal with it.
   mFrames = new FrameSequence();
 }
 void
 FrameBlender::InsertFrame(uint32_t framenum, imgFrame* aFrame)
 {
   NS_ABORT_IF_FALSE(framenum <= GetNumFrames(), "Inserting invalid frame!");
   mFrames->InsertFrame(framenum, aFrame);
   if (GetNumFrames() > 1) {
     EnsureAnimExists();
   }
 }
 imgFrame*
 FrameBlender::SwapFrame(uint32_t framenum, imgFrame* aFrame)
 {
   NS_ABORT_IF_FALSE(framenum < GetNumFrames(), "Swapping invalid frame!");
   imgFrame* ret;
   // Steal the imgFrame from wherever it's currently stored
   if (mAnim && mAnim->lastCompositedFrameIndex == int32_t(framenum)) {
     ret = mAnim->compositingFrame.Forget();
     mAnim->lastCompositedFrameIndex = -1;
     nsAutoPtr<imgFrame> toDelete(mFrames->SwapFrame(framenum, aFrame));
   } else {
     ret = mFrames->SwapFrame(framenum, aFrame);
   }
   return ret;
 }
 void
 FrameBlender::EnsureAnimExists()
 {
   if (!mAnim) {
     // Create the animation context
     mAnim = new Anim();
     // We should only get into this code path directly after we've created our
     // second frame (hence we know we're animated).
     MOZ_ASSERT(GetNumFrames() == 2);
   }
 }
 //******************************************************************************
 // DoBlend gets called when the timer for animation get fired and we have to
 // update the composited frame of the animation.
 bool
 FrameBlender::DoBlend(nsIntRect* aDirtyRect,
                       uint32_t aPrevFrameIndex,
                       uint32_t aNextFrameIndex)
 {
   if (!aDirtyRect) {
     return false;
   }
   const FrameDataPair& prevFrame = mFrames->GetFrame(aPrevFrameIndex);
   const FrameDataPair& nextFrame = mFrames->GetFrame(aNextFrameIndex);
   if (!prevFrame.HasFrameData() || !nextFrame.HasFrameData()) {
     return false;
   }
   int32_t prevFrameDisposalMethod = prevFrame->GetFrameDisposalMethod();
   if (prevFrameDisposalMethod == FrameBlender::kDisposeRestorePrevious &&
       !mAnim->compositingPrevFrame)
     prevFrameDisposalMethod = FrameBlender::kDisposeClear;
   nsIntRect prevFrameRect = prevFrame->GetRect();
   bool isFullPrevFrame = (prevFrameRect.x == 0 && prevFrameRect.y == 0 &&
                           prevFrameRect.width == mSize.width &&
                           prevFrameRect.height == mSize.height);
   // Optimization: DisposeClearAll if the previous frame is the same size as
   //               container and it's clearing itself
   if (isFullPrevFrame &&
       (prevFrameDisposalMethod == FrameBlender::kDisposeClear))
     prevFrameDisposalMethod = FrameBlender::kDisposeClearAll;
   int32_t nextFrameDisposalMethod = nextFrame->GetFrameDisposalMethod();
   nsIntRect nextFrameRect = nextFrame->GetRect();
   bool isFullNextFrame = (nextFrameRect.x == 0 && nextFrameRect.y == 0 &&
                           nextFrameRect.width == mSize.width &&
                           nextFrameRect.height == mSize.height);
   if (!nextFrame->GetIsPaletted()) {
     // Optimization: Skip compositing if the previous frame wants to clear the
     //               whole image
     if (prevFrameDisposalMethod == FrameBlender::kDisposeClearAll) {
       aDirtyRect->SetRect(0, 0, mSize.width, mSize.height);
       return true;
     }
     // Optimization: Skip compositing if this frame is the same size as the
     //               container and it's fully drawing over prev frame (no alpha)
     if (isFullNextFrame &&
         (nextFrameDisposalMethod != FrameBlender::kDisposeRestorePrevious) &&
         !nextFrame->GetHasAlpha()) {
       aDirtyRect->SetRect(0, 0, mSize.width, mSize.height);
       return true;
     }
   }
   // Calculate area that needs updating
   switch (prevFrameDisposalMethod) {
     default:
     case FrameBlender::kDisposeNotSpecified:
     case FrameBlender::kDisposeKeep:
       *aDirtyRect = nextFrameRect;
       break;
     case FrameBlender::kDisposeClearAll:
       // Whole image container is cleared
       aDirtyRect->SetRect(0, 0, mSize.width, mSize.height);
       break;
     case FrameBlender::kDisposeClear:
       // Calc area that needs to be redrawn (the combination of previous and
       // this frame)
       // XXX - This could be done with multiple framechanged calls
       //       Having prevFrame way at the top of the image, and nextFrame
       //       way at the bottom, and both frames being small, we'd be
       //       telling framechanged to refresh the whole image when only two
       //       small areas are needed.
       aDirtyRect->UnionRect(nextFrameRect, prevFrameRect);
       break;
     case FrameBlender::kDisposeRestorePrevious:
       aDirtyRect->SetRect(0, 0, mSize.width, mSize.height);
       break;
   }
   // Optimization:
   //   Skip compositing if the last composited frame is this frame
   //   (Only one composited frame was made for this animation.  Example:
   //    Only Frame 3 of a 10 frame image required us to build a composite frame
   //    On the second loop, we do not need to rebuild the frame
   //    since it's still sitting in compositingFrame)
   if (mAnim->lastCompositedFrameIndex == int32_t(aNextFrameIndex)) {
     return true;
   }
   bool needToBlankComposite = false;
   // Create the Compositing Frame
   if (!mAnim->compositingFrame) {
     mAnim->compositingFrame.SetFrame(new imgFrame());
     nsresult rv = mAnim->compositingFrame->Init(0, 0, mSize.width, mSize.height,
                                                 gfxImageFormat::ARGB32);
     if (NS_FAILED(rv)) {
       mAnim->compositingFrame.SetFrame(nullptr);
       return false;
     }
     mAnim->compositingFrame.LockAndGetData();
     needToBlankComposite = true;
   } else if (int32_t(aNextFrameIndex) != mAnim->lastCompositedFrameIndex+1) {
     // If we are not drawing on top of last composited frame,
     // then we are building a new composite frame, so let's clear it first.
     needToBlankComposite = true;
   }
   // More optimizations possible when next frame is not transparent
   // But if the next frame has FrameBlender::kDisposeRestorePrevious,
   // this "no disposal" optimization is not possible,
   // because the frame in "after disposal operation" state
   // needs to be stored in compositingFrame, so it can be
   // copied into compositingPrevFrame later.
   bool doDisposal = true;
   if (!nextFrame->GetHasAlpha() &&
       nextFrameDisposalMethod != FrameBlender::kDisposeRestorePrevious) {
     if (isFullNextFrame) {
       // Optimization: No need to dispose prev.frame when
       // next frame is full frame and not transparent.
       doDisposal = false;
       // No need to blank the composite frame
       needToBlankComposite = false;
     } else {
       if ((prevFrameRect.x >= nextFrameRect.x) &&
           (prevFrameRect.y >= nextFrameRect.y) &&
           (prevFrameRect.x + prevFrameRect.width <= nextFrameRect.x + nextFrameRect.width) &&
           (prevFrameRect.y + prevFrameRect.height <= nextFrameRect.y + nextFrameRect.height)) {
         // Optimization: No need to dispose prev.frame when
         // next frame fully overlaps previous frame.
         doDisposal = false;
       }
     }
   }
   if (doDisposal) {
     // Dispose of previous: clear, restore, or keep (copy)
     switch (prevFrameDisposalMethod) {
       case FrameBlender::kDisposeClear:
         if (needToBlankComposite) {
           // If we just created the composite, it could have anything in its
           // buffer. Clear whole frame
           ClearFrame(mAnim->compositingFrame.GetFrameData(),
                      mAnim->compositingFrame.GetFrame()->GetRect());
         } else {
           // Only blank out previous frame area (both color & Mask/Alpha)
           ClearFrame(mAnim->compositingFrame.GetFrameData(),
                      mAnim->compositingFrame.GetFrame()->GetRect(),
                      prevFrameRect);
         }
         break;
       case FrameBlender::kDisposeClearAll:
         ClearFrame(mAnim->compositingFrame.GetFrameData(),
                    mAnim->compositingFrame.GetFrame()->GetRect());
         break;
       case FrameBlender::kDisposeRestorePrevious:
         // It would be better to copy only the area changed back to
         // compositingFrame.
         if (mAnim->compositingPrevFrame) {
           CopyFrameImage(mAnim->compositingPrevFrame.GetFrameData(),
                          mAnim->compositingPrevFrame.GetFrame()->GetRect(),
                          mAnim->compositingFrame.GetFrameData(),
                          mAnim->compositingFrame.GetFrame()->GetRect());
           // destroy only if we don't need it for this frame's disposal
           if (nextFrameDisposalMethod != FrameBlender::kDisposeRestorePrevious)
             mAnim->compositingPrevFrame.SetFrame(nullptr);
         } else {
           ClearFrame(mAnim->compositingFrame.GetFrameData(),
                      mAnim->compositingFrame.GetFrame()->GetRect());
         }
         break;
       default:
         // Copy previous frame into compositingFrame before we put the new frame on top
         // Assumes that the previous frame represents a full frame (it could be
         // smaller in size than the container, as long as the frame before it erased
         // itself)
         // Note: Frame 1 never gets into DoBlend(), so (aNextFrameIndex - 1) will
         // always be a valid frame number.
         if (mAnim->lastCompositedFrameIndex != int32_t(aNextFrameIndex - 1)) {
           if (isFullPrevFrame && !prevFrame->GetIsPaletted()) {
             // Just copy the bits
             CopyFrameImage(prevFrame.GetFrameData(),
                            prevFrame.GetFrame()->GetRect(),
                            mAnim->compositingFrame.GetFrameData(),
                            mAnim->compositingFrame.GetFrame()->GetRect());
           } else {
             if (needToBlankComposite) {
               // Only blank composite when prev is transparent or not full.
               if (prevFrame->GetHasAlpha() || !isFullPrevFrame) {
                 ClearFrame(mAnim->compositingFrame.GetFrameData(),
                            mAnim->compositingFrame.GetFrame()->GetRect());
               }
             }
             DrawFrameTo(prevFrame.GetFrameData(), prevFrameRect,
                         prevFrame.GetFrame()->PaletteDataLength(),
                         prevFrame.GetFrame()->GetHasAlpha(),
                         mAnim->compositingFrame.GetFrameData(),
                         mAnim->compositingFrame.GetFrame()->GetRect(),
                         FrameBlendMethod(prevFrame.GetFrame()->GetBlendMethod()));
           }
         }
     }
   } else if (needToBlankComposite) {
     // If we just created the composite, it could have anything in it's
     // buffers. Clear them
     ClearFrame(mAnim->compositingFrame.GetFrameData(),
                mAnim->compositingFrame.GetFrame()->GetRect());
   }
   // Check if the frame we are composing wants the previous image restored afer
   // it is done. Don't store it (again) if last frame wanted its image restored
   // too
   if ((nextFrameDisposalMethod == FrameBlender::kDisposeRestorePrevious) &&
       (prevFrameDisposalMethod != FrameBlender::kDisposeRestorePrevious)) {
     // We are storing the whole image.
     // It would be better if we just stored the area that nextFrame is going to
     // overwrite.
     if (!mAnim->compositingPrevFrame) {
       mAnim->compositingPrevFrame.SetFrame(new imgFrame());
       nsresult rv = mAnim->compositingPrevFrame->Init(0, 0, mSize.width, mSize.height,
                                                       gfxImageFormat::ARGB32);
       if (NS_FAILED(rv)) {
         mAnim->compositingPrevFrame.SetFrame(nullptr);
         return false;
       }
       mAnim->compositingPrevFrame.LockAndGetData();
     }
     CopyFrameImage(mAnim->compositingFrame.GetFrameData(),
                    mAnim->compositingFrame.GetFrame()->GetRect(),
                    mAnim->compositingPrevFrame.GetFrameData(),
                    mAnim->compositingPrevFrame.GetFrame()->GetRect());
   }
   // blit next frame into it's correct spot
   DrawFrameTo(nextFrame.GetFrameData(), nextFrameRect,
               nextFrame.GetFrame()->PaletteDataLength(),
               nextFrame.GetFrame()->GetHasAlpha(),
               mAnim->compositingFrame.GetFrameData(),
               mAnim->compositingFrame.GetFrame()->GetRect(),
               FrameBlendMethod(nextFrame.GetFrame()->GetBlendMethod()));
   // Set timeout of CompositeFrame to timeout of frame we just composed
   // Bug 177948
   int32_t timeout = nextFrame->GetRawTimeout();
   mAnim->compositingFrame->SetRawTimeout(timeout);
   // Tell the image that it is fully 'downloaded'.
   nsresult rv = mAnim->compositingFrame->ImageUpdated(mAnim->compositingFrame->GetRect());
   if (NS_FAILED(rv)) {
     return false;
   }
   mAnim->lastCompositedFrameIndex = int32_t(aNextFrameIndex);
   return true;
 }
 //******************************************************************************
 // Fill aFrame with black. Does also clears the mask.
 void
 FrameBlender::ClearFrame(uint8_t* aFrameData, const nsIntRect& aFrameRect)
 {
   if (!aFrameData)
     return;
   memset(aFrameData, 0, aFrameRect.width * aFrameRect.height * 4);
 }
 //******************************************************************************
 void
 FrameBlender::ClearFrame(uint8_t* aFrameData, const nsIntRect& aFrameRect, const nsIntRect& aRectToClear)
 {
   if (!aFrameData || aFrameRect.width <= 0 || aFrameRect.height <= 0 ||
       aRectToClear.width <= 0 || aRectToClear.height <= 0) {
     return;
   }
   nsIntRect toClear = aFrameRect.Intersect(aRectToClear);
   if (toClear.IsEmpty()) {
     return;
   }
   uint32_t bytesPerRow = aFrameRect.width * 4;
   for (int row = toClear.y; row < toClear.y + toClear.height; ++row) {
     memset(aFrameData + toClear.x * 4 + row * bytesPerRow, 0, toClear.width * 4);
   }
 }
 //******************************************************************************
 // Whether we succeed or fail will not cause a crash, and there's not much
 // we can do about a failure, so there we don't return a nsresult
 bool
 FrameBlender::CopyFrameImage(const uint8_t *aDataSrc, const nsIntRect& aRectSrc,
                              uint8_t *aDataDest, const nsIntRect& aRectDest)
 {
   uint32_t dataLengthSrc = aRectSrc.width * aRectSrc.height * 4;
   uint32_t dataLengthDest = aRectDest.width * aRectDest.height * 4;
   if (!aDataDest || !aDataSrc || dataLengthSrc != dataLengthDest) {
     return false;
   }
   memcpy(aDataDest, aDataSrc, dataLengthDest);
   return true;
 }
 nsresult
 FrameBlender::DrawFrameTo(const uint8_t *aSrcData, const nsIntRect& aSrcRect,
                           uint32_t aSrcPaletteLength, bool aSrcHasAlpha,
                           uint8_t *aDstPixels, const nsIntRect& aDstRect,
                           FrameBlender::FrameBlendMethod aBlendMethod)
 {
   NS_ENSURE_ARG_POINTER(aSrcData);
   NS_ENSURE_ARG_POINTER(aDstPixels);
   // According to both AGIF and APNG specs, offsets are unsigned
   if (aSrcRect.x < 0 || aSrcRect.y < 0) {
     NS_WARNING("FrameBlender::DrawFrameTo: negative offsets not allowed");
     return NS_ERROR_FAILURE;
   }
   // Outside the destination frame, skip it
   if ((aSrcRect.x > aDstRect.width) || (aSrcRect.y > aDstRect.height)) {
     return NS_OK;
   }
   if (aSrcPaletteLength) {
     // Larger than the destination frame, clip it
     int32_t width = std::min(aSrcRect.width, aDstRect.width - aSrcRect.x);
     int32_t height = std::min(aSrcRect.height, aDstRect.height - aSrcRect.y);
     // The clipped image must now fully fit within destination image frame
     NS_ASSERTION((aSrcRect.x >= 0) && (aSrcRect.y >= 0) &&
                  (aSrcRect.x + width <= aDstRect.width) &&
                  (aSrcRect.y + height <= aDstRect.height),
                 "FrameBlender::DrawFrameTo: Invalid aSrcRect");
     // clipped image size may be smaller than source, but not larger
     NS_ASSERTION((width <= aSrcRect.width) && (height <= aSrcRect.height),
                  "FrameBlender::DrawFrameTo: source must be smaller than dest");
     // Get pointers to image data
     const uint8_t *srcPixels = aSrcData + aSrcPaletteLength;
     uint32_t *dstPixels = reinterpret_cast<uint32_t*>(aDstPixels);
     const uint32_t *colormap = reinterpret_cast<const uint32_t*>(aSrcData);
     // Skip to the right offset
     dstPixels += aSrcRect.x + (aSrcRect.y * aDstRect.width);
     if (!aSrcHasAlpha) {
       for (int32_t r = height; r > 0; --r) {
         for (int32_t c = 0; c < width; c++) {
           dstPixels[c] = colormap[srcPixels[c]];
         }
         // Go to the next row in the source resp. destination image
         srcPixels += aSrcRect.width;
         dstPixels += aDstRect.width;
       }
     } else {
       for (int32_t r = height; r > 0; --r) {
         for (int32_t c = 0; c < width; c++) {
           const uint32_t color = colormap[srcPixels[c]];
           if (color)
             dstPixels[c] = color;
         }
         // Go to the next row in the source resp. destination image
         srcPixels += aSrcRect.width;
         dstPixels += aDstRect.width;
       }
     }
   } else {
     pixman_image_t* src = pixman_image_create_bits(aSrcHasAlpha ? PIXMAN_a8r8g8b8 : PIXMAN_x8r8g8b8,
                                                    aSrcRect.width,
                                                    aSrcRect.height,
                                                    reinterpret_cast<uint32_t*>(const_cast<uint8_t*>(aSrcData)),
                                                    aSrcRect.width * 4);
     pixman_image_t* dst = pixman_image_create_bits(PIXMAN_a8r8g8b8,
                                                    aDstRect.width,
                                                    aDstRect.height,
                                                    reinterpret_cast<uint32_t*>(aDstPixels),
                                                    aDstRect.width * 4);
     pixman_image_composite32(aBlendMethod == FrameBlender::kBlendSource ? PIXMAN_OP_SRC : PIXMAN_OP_OVER,
                              src,
                              nullptr,
                              dst,
 , 0,
 , 0,
                              aSrcRect.x, aSrcRect.y,
                              aSrcRect.width, aSrcRect.height);
     pixman_image_unref(src);
     pixman_image_unref(dst);
   }
   return NS_OK;
 }
 void
 FrameBlender::Discard()
 {
   MOZ_ASSERT(NS_IsMainThread());
   // As soon as an image becomes animated, it becomes non-discardable and any
   // timers are cancelled.
   NS_ABORT_IF_FALSE(!mAnim, "Asked to discard for animated image!");
   // Delete all the decoded frames, then clear the array.
   ClearFrames();
 }
 size_t
 FrameBlender::SizeOfDecodedWithComputedFallbackIfHeap(gfxMemoryLocation aLocation,
                                                       MallocSizeOf aMallocSizeOf) const
 {
   size_t n = mFrames->SizeOfDecodedWithComputedFallbackIfHeap(aLocation, aMallocSizeOf);
   if (mAnim) {
     if (mAnim->compositingFrame) {
       n += mAnim->compositingFrame->SizeOfExcludingThisWithComputedFallbackIfHeap(aLocation, aMallocSizeOf);
     }
     if (mAnim->compositingPrevFrame) {
       n += mAnim->compositingPrevFrame->SizeOfExcludingThisWithComputedFallbackIfHeap(aLocation, aMallocSizeOf);
     }
   }
   return n;
 }
 void
 FrameBlender::ResetAnimation()
 {
   if (mAnim) {
     mAnim->lastCompositedFrameIndex = -1;
   }
 }
 } // namespace image
 } // namespace mozilla

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image/src/FrameBlender.cpp@6474c204b198 (annotated)

image/src/FrameBlender.cpp