Adding upstream version 115.8.0esr.upstream/115.8.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 343 insertions, 0 deletions

diff --git a/image/FrameAnimator.h b/image/FrameAnimator.h
new file mode 100644
index 0000000000..40538a3beb
--- /dev/null
+++ b/image/FrameAnimator.h
@@ -0,0 +1,343 @@
+/* -*- 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/. */
+
+#ifndef mozilla_image_FrameAnimator_h
+#define mozilla_image_FrameAnimator_h
+
+#include "mozilla/Maybe.h"
+#include "mozilla/StaticPrefs_image.h"
+#include "mozilla/TimeStamp.h"
+#include "gfxTypes.h"
+#include "imgFrame.h"
+#include "nsCOMPtr.h"
+#include "nsRect.h"
+#include "SurfaceCache.h"
+
+namespace mozilla {
+namespace image {
+
+class RasterImage;
+class DrawableSurface;
+
+class AnimationState {
+ public:
+  explicit AnimationState(uint16_t aAnimationMode)
+      : mFrameCount(0),
+        mCurrentAnimationFrameIndex(0),
+        mLoopRemainingCount(-1),
+        mLoopCount(-1),
+        mFirstFrameTimeout(FrameTimeout::FromRawMilliseconds(0)),
+        mAnimationMode(aAnimationMode),
+        mHasBeenDecoded(false),
+        mHasRequestedDecode(false),
+        mIsCurrentlyDecoded(false),
+        mCompositedFrameInvalid(false),
+        mDiscarded(false) {}
+
+  /**
+   * Call this whenever a decode completes, a decode starts, or the image is
+   * discarded. It will update the internal state. Specifically mDiscarded,
+   * mCompositedFrameInvalid, and mIsCurrentlyDecoded. If aAllowInvalidation
+   * is true then returns a rect to invalidate.
+   */
+  const gfx::IntRect UpdateState(RasterImage* aImage, const gfx::IntSize& aSize,
+                                 bool aAllowInvalidation = true);
+
+ private:
+  const gfx::IntRect UpdateStateInternal(LookupResult& aResult,
+                                         const gfx::IntSize& aSize,
+                                         bool aAllowInvalidation = true);
+
+ public:
+  /**
+   * Call when a decode of this image has been completed.
+   */
+  void NotifyDecodeComplete();
+
+  /**
+   * Returns true if this image has been fully decoded before.
+   */
+  bool GetHasBeenDecoded() { return mHasBeenDecoded; }
+
+  /**
+   * Returns true if this image has ever requested a decode before.
+   */
+  bool GetHasRequestedDecode() { return mHasRequestedDecode; }
+
+  /**
+   * Returns true if this image has been discarded and a decoded has not yet
+   * been created to redecode it.
+   */
+  bool IsDiscarded() { return mDiscarded; }
+
+  /**
+   * Sets the composited frame as valid or invalid.
+   */
+  void SetCompositedFrameInvalid(bool aInvalid) {
+    MOZ_ASSERT(!aInvalid ||
+               StaticPrefs::image_mem_animated_discardable_AtStartup());
+    mCompositedFrameInvalid = aInvalid;
+  }
+
+  /**
+   * Returns whether the composited frame is valid to draw to the screen.
+   */
+  bool GetCompositedFrameInvalid() { return mCompositedFrameInvalid; }
+
+  /**
+   * Returns whether the image is currently full decoded..
+   */
+  bool GetIsCurrentlyDecoded() { return mIsCurrentlyDecoded; }
+
+  /**
+   * Call when you need to re-start animating. Ensures we start from the first
+   * frame.
+   */
+  void ResetAnimation();
+
+  /**
+   * The animation mode of the image.
+   *
+   * Constants defined in imgIContainer.idl.
+   */
+  void SetAnimationMode(uint16_t aAnimationMode);
+
+  /// Update the number of frames of animation this image is known to have.
+  void UpdateKnownFrameCount(uint32_t aFrameCount);
+
+  /// @return the number of frames of animation we know about so far.
+  uint32_t KnownFrameCount() const { return mFrameCount; }
+
+  /// @return the number of frames this animation has, if we know for sure.
+  /// (In other words, if decoding is finished.) Otherwise, returns Nothing().
+  Maybe<uint32_t> FrameCount() const;
+
+  /**
+   * Get or set the area of the image to invalidate when we loop around to the
+   * first frame.
+   */
+  void SetFirstFrameRefreshArea(const gfx::IntRect& aRefreshArea);
+  gfx::IntRect FirstFrameRefreshArea() const { return mFirstFrameRefreshArea; }
+
+  /**
+   * If the animation frame time has not yet been set, set it to
+   * TimeStamp::Now().
+   */
+  void InitAnimationFrameTimeIfNecessary();
+
+  /**
+   * Set the animation frame time to @aTime.
+   */
+  void SetAnimationFrameTime(const TimeStamp& aTime);
+
+  /**
+   * Set the animation frame time to @aTime if we are configured to stop the
+   * animation when not visible and aTime is later than the current time.
+   * Returns true if the time was updated, else false.
+   */
+  bool MaybeAdvanceAnimationFrameTime(const TimeStamp& aTime);
+
+  /**
+   * The current frame we're on, from 0 to (numFrames - 1).
+   */
+  uint32_t GetCurrentAnimationFrameIndex() const;
+
+  /*
+   * Set number of times to loop the image.
+   * @note -1 means loop forever.
+   */
+  void SetLoopCount(int32_t aLoopCount) { mLoopCount = aLoopCount; }
+  int32_t LoopCount() const { return mLoopCount; }
+
+  /// Set the @aLength of a single loop through this image.
+  void SetLoopLength(FrameTimeout aLength) { mLoopLength = Some(aLength); }
+
+  /**
+   * @return the length of a single loop of this image. If this image is not
+   * finished decoding, is not animated, or it is animated but does not loop,
+   * returns FrameTimeout::Forever().
+   */
+  FrameTimeout LoopLength() const;
+
+  /*
+   * Get or set the timeout for the first frame. This is used to allow animation
+   * scheduling even before a full decode runs for this image.
+   */
+  void SetFirstFrameTimeout(FrameTimeout aTimeout) {
+    mFirstFrameTimeout = aTimeout;
+  }
+  FrameTimeout FirstFrameTimeout() const { return mFirstFrameTimeout; }
+
+ private:
+  friend class FrameAnimator;
+
+  //! Area of the first frame that needs to be redrawn on subsequent loops.
+  gfx::IntRect mFirstFrameRefreshArea;
+
+  //! the time that the animation advanced to the current frame
+  TimeStamp mCurrentAnimationFrameTime;
+
+  //! The number of frames of animation this image has.
+  uint32_t mFrameCount;
+
+  //! The current frame index we're on, in the range [0, mFrameCount).
+  uint32_t mCurrentAnimationFrameIndex;
+
+  //! number of loops remaining before animation stops (-1 no stop)
+  int32_t mLoopRemainingCount;
+
+  //! The total number of loops for the image.
+  int32_t mLoopCount;
+
+  //! The length of a single loop through this image.
+  Maybe<FrameTimeout> mLoopLength;
+
+  //! The timeout for the first frame of this image.
+  FrameTimeout mFirstFrameTimeout;
+
+  //! The animation mode of this image. Constants defined in imgIContainer.
+  uint16_t mAnimationMode;
+
+  /**
+   * The following four bools (mHasBeenDecoded, mIsCurrentlyDecoded,
+   * mCompositedFrameInvalid, mDiscarded) track the state of the image with
+   * regards to decoding. They all start out false, including mDiscarded,
+   * because we want to treat being discarded differently from "not yet decoded
+   * for the first time".
+   *
+   * (When we are decoding the image for the first time we want to show the
+   * image at the speed of data coming in from the network or the speed
+   * specified in the image file, whichever is slower. But when redecoding we
+   * want to show nothing until the frame for the current time has been
+   * decoded. The prevents the user from seeing the image "fast forward"
+   * to the expected spot.)
+   *
+   * When the image is decoded for the first time mHasBeenDecoded and
+   * mIsCurrentlyDecoded get set to true. When the image is discarded
+   * mIsCurrentlyDecoded gets set to false, and mCompositedFrameInvalid
+   * & mDiscarded get set to true. When we create a decoder to redecode the
+   * image mDiscarded gets set to false. mCompositedFrameInvalid gets set to
+   * false when we are able to advance to the frame that should be showing
+   * for the current time. mIsCurrentlyDecoded gets set to true when the
+   * redecode finishes.
+   */
+
+  //! Whether this image has been decoded at least once.
+  bool mHasBeenDecoded;
+
+  //! Whether this image has ever requested a decode.
+  bool mHasRequestedDecode;
+
+  //! Whether this image is currently fully decoded.
+  bool mIsCurrentlyDecoded;
+
+  //! Whether the composited frame is valid to draw to the screen, note that
+  //! the composited frame can exist and be filled with image data but not
+  //! valid to draw to the screen.
+  bool mCompositedFrameInvalid;
+
+  //! Whether this image is currently discarded. Only set to true after the
+  //! image has been decoded at least once.
+  bool mDiscarded;
+};
+
+/**
+ * RefreshResult is used to let callers know how the state of the animation
+ * changed during a call to FrameAnimator::RequestRefresh().
+ */
+struct RefreshResult {
+  RefreshResult() : mFrameAdvanced(false), mAnimationFinished(false) {}
+
+  /// Merges another RefreshResult's changes into this RefreshResult.
+  void Accumulate(const RefreshResult& aOther) {
+    mFrameAdvanced = mFrameAdvanced || aOther.mFrameAdvanced;
+    mAnimationFinished = mAnimationFinished || aOther.mAnimationFinished;
+    mDirtyRect = mDirtyRect.Union(aOther.mDirtyRect);
+  }
+
+  // The region of the image that has changed.
+  gfx::IntRect mDirtyRect;
+
+  // If true, we changed frames at least once. Note that, due to looping, we
+  // could still have ended up on the same frame!
+  bool mFrameAdvanced : 1;
+
+  // Whether the animation has finished playing.
+  bool mAnimationFinished : 1;
+};
+
+class FrameAnimator {
+ public:
+  FrameAnimator(RasterImage* aImage, const gfx::IntSize& aSize)
+      : mImage(aImage), mSize(aSize) {
+    MOZ_COUNT_CTOR(FrameAnimator);
+  }
+
+  MOZ_COUNTED_DTOR(FrameAnimator)
+
+  /**
+   * Call when you need to re-start animating. Ensures we start from the first
+   * frame.
+   */
+  void ResetAnimation(AnimationState& aState);
+
+  /**
+   * Re-evaluate what frame we're supposed to be on, and do whatever blending
+   * is necessary to get us to that frame.
+   *
+   * Returns the result of that blending, including whether the current frame
+   * changed and what the resulting dirty rectangle is.
+   */
+  RefreshResult RequestRefresh(AnimationState& aState, const TimeStamp& aTime);
+
+  /**
+   * Get the full frame for the current frame of the animation (it may or may
+   * not have required compositing). It may not be available because it hasn't
+   * been decoded yet, in which case we return an empty LookupResult.
+   */
+  LookupResult GetCompositedFrame(AnimationState& aState, bool aMarkUsed);
+
+ private:  // methods
+  /**
+   * Advances the animation. Typically, this will advance a single frame, but it
+   * may advance multiple frames. This may happen if we have infrequently
+   * "ticking" refresh drivers (e.g. in background tabs), or extremely short-
+   * lived animation frames.
+   *
+   * @param aTime the time that the animation should advance to. This will
+   *              typically be <= TimeStamp::Now().
+   *
+   * @param aCurrentFrame the currently displayed frame of the animation. If
+   *                      we advance, it will replace aCurrentFrame with the
+   *                      new current frame we advanced to.
+   *
+   * @returns a RefreshResult that shows whether the frame was successfully
+   *          advanced, and its resulting dirty rect.
+   */
+  RefreshResult AdvanceFrame(AnimationState& aState, DrawableSurface& aFrames,
+                             RefPtr<imgFrame>& aCurrentFrame, TimeStamp aTime);
+
+  /**
+   * Get the time the frame we're currently displaying is supposed to end.
+   *
+   * In the error case (like if the requested frame is not currently
+   * decoded), returns None().
+   */
+  TimeStamp GetCurrentImgFrameEndTime(AnimationState& aState,
+                                      FrameTimeout aCurrentTimeout) const;
+
+ private:  // data
+  //! A weak pointer to our owning image.
+  RasterImage* mImage;
+
+  //! The intrinsic size of the image.
+  gfx::IntSize mSize;
+};
+
+}  // namespace image
+}  // namespace mozilla
+
+#endif  // mozilla_image_FrameAnimator_h