Bug 1118092 - Manage invalidation policy directly in the image decoder. r=tn

image/decoders/nsICODecoder.cpp

@@ -345,6 +345,7 @@ nsICODecoder::WriteInternal(const char* aBuffer, uint32_t aCount)
     if (mIsPNG) {
       mContainedDecoder = new nsPNGDecoder(mImage);
       mContainedDecoder->SetSizeDecode(IsSizeDecode());
+      mContainedDecoder->SetSendPartialInvalidations(mSendPartialInvalidations);
       mContainedDecoder->Init();
       if (!WriteToContainedDecoder(mSignature, PNGSIGNATURESIZE)) {
         return;
@@ -421,6 +422,7 @@ nsICODecoder::WriteInternal(const char* aBuffer, uint32_t aCount)
     mContainedDecoder = bmpDecoder;
     bmpDecoder->SetUseAlphaData(true);
     mContainedDecoder->SetSizeDecode(IsSizeDecode());
+    mContainedDecoder->SetSendPartialInvalidations(mSendPartialInvalidations);
     mContainedDecoder->Init();
 
     // The ICO format when containing a BMP does not include the 14 byte

image/src/Decoder.cpp

@@ -28,6 +28,7 @@ Decoder::Decoder(RasterImage &aImage)
   , mChunkCount(0)
   , mDecodeFlags(0)
   , mBytesDecoded(0)
+  , mSendPartialInvalidations(false)
   , mDecodeDone(false)
   , mDataError(false)
   , mFrameCount(0)
@@ -364,6 +365,12 @@ Decoder::PostFrameStop(Opacity aFrameOpacity /* = Opacity::TRANSPARENT */,
   mCurrentFrame->Finish(aFrameOpacity, aDisposalMethod, aTimeout, aBlendMethod);
 
   mProgress |= FLAG_FRAME_COMPLETE | FLAG_ONLOAD_UNBLOCKED;
+
+  // If we're not sending partial invalidations, then we send an invalidation
+  // here when the first frame is complete.
+  if (!mSendPartialInvalidations && !mIsAnimated) {
+    mInvalidRect.UnionRect(mInvalidRect, mCurrentFrame->GetRect());
+  }
 }
 
 void
@@ -373,9 +380,12 @@ Decoder::PostInvalidation(nsIntRect& aRect)
   NS_ABORT_IF_FALSE(mInFrame, "Can't invalidate when not mid-frame!");
   NS_ABORT_IF_FALSE(mCurrentFrame, "Can't invalidate when not mid-frame!");
 
-  // Account for the new region
-  mInvalidRect.UnionRect(mInvalidRect, aRect);
-  mCurrentFrame->ImageUpdated(aRect);
+  // Record this invalidation, unless we're not sending partial invalidations
+  // or we're past the first frame.
+  if (mSendPartialInvalidations && !mIsAnimated) {
+    mInvalidRect.UnionRect(mInvalidRect, aRect);
+    mCurrentFrame->ImageUpdated(aRect);
+  }
 }
 
 void

image/src/Decoder.h

@@ -92,6 +92,24 @@ public:
     mSizeDecode = aSizeDecode;
   }
 
+  /**
+   * Set whether should send partial invalidations.
+   *
+   * If @aSend is true, we'll send partial invalidations when decoding the first
+   * frame of the image, so image notifications observers will be able to
+   * gradually draw in the image as it downloads.
+   *
+   * If @aSend is false (the default), we'll only send an invalidation when we
+   * complete the first frame.
+   *
+   * This must be called before Init() is called.
+   */
+  void SetSendPartialInvalidations(bool aSend)
+  {
+    MOZ_ASSERT(!mInitialized, "Shouldn't be initialized yet");
+    mSendPartialInvalidations = aSend;
+  }
+
   size_t BytesDecoded() const { return mBytesDecoded; }
 
   // The amount of time we've spent inside Write() so far for this decoder.
@@ -262,6 +280,7 @@ protected:
 
   uint32_t mDecodeFlags;
   size_t mBytesDecoded;
+  bool mSendPartialInvalidations;
   bool mDecodeDone;
   bool mDataError;
 

image/src/RasterImage.cpp

@@ -1505,6 +1505,7 @@ RasterImage::InitDecoder(bool aDoSizeDecode)
   // Initialize the decoder
   mDecoder->SetSizeDecode(aDoSizeDecode);
   mDecoder->SetDecodeFlags(mFrameDecodeFlags);
+  mDecoder->SetSendPartialInvalidations(!mHasBeenDecoded);
   mDecoder->Init();
   CONTAINER_ENSURE_SUCCESS(mDecoder->GetDecoderError());
 
@@ -2407,16 +2408,6 @@ RasterImage::FinishedSomeDecoding(ShutdownReason aReason /* = ShutdownReason::DO
     }
   }
 
-  if (GetCurrentFrameIndex() > 0) {
-    // Don't send invalidations for animated frames after the first; let
-    // RequestRefresh take care of that.
-    invalidRect = nsIntRect();
-  }
-  if (mHasBeenDecoded && !invalidRect.IsEmpty()) {
-    // Don't send partial invalidations if we've been decoded before.
-    invalidRect = mDecoded ? GetFirstFrameRect()
-                           : nsIntRect();
-  }
   if (!invalidRect.IsEmpty() && wasDefaultFlags) {
     // Update our image container since we're invalidating.
     UpdateImageContainer();