1 files changed, 438 insertions, 0 deletions
diff --git a/WebCore/platform/graphics/BitmapImage.cpp b/WebCore/platform/graphics/BitmapImage.cpp
new file mode 100644
index 0000000..4b21de0
--- /dev/null
+++ b/WebCore/platform/graphics/BitmapImage.cpp
@@ -0,0 +1,438 @@
+/*
+ * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
+ * Copyright (C) 2004, 2005, 2006, 2008 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#include "config.h"
+#include "BitmapImage.h"
+
+#include "FloatRect.h"
+#include "ImageObserver.h"
+#include "IntRect.h"
+#include "PlatformString.h"
+#include "SystemTime.h"
+#include "Timer.h"
+#include <wtf/Vector.h>
+#include "MIMETypeRegistry.h"
+
+namespace WebCore {
+
+// Animated images >5MB are considered large enough that we'll only hang on to
+// one frame at a time.
+const unsigned cLargeAnimationCutoff = 5242880;
+
+// When an animated image is more than five minutes out of date, don't try to
+// resync on repaint, so we don't waste CPU cycles on an edge case the user
+// doesn't care about.
+const double cAnimationResyncCutoff = 5 * 60;
+
+BitmapImage::BitmapImage(ImageObserver* observer)
+    : Image(observer)
+    , m_currentFrame(0)
+    , m_frames(0)
+    , m_frameTimer(0)
+    , m_repetitionCount(cAnimationNone)
+    , m_repetitionCountStatus(Unknown)
+    , m_repetitionsComplete(0)
+    , m_desiredFrameStartTime(0)
+    , m_isSolidColor(false)
+    , m_animationFinished(false)
+    , m_allDataReceived(false)
+    , m_haveSize(false)
+    , m_sizeAvailable(false)
+    , m_hasUniformFrameSize(true)
+    , m_decodedSize(0)
+    , m_haveFrameCount(false)
+    , m_frameCount(0)
+{
+    initPlatformData();
+}
+
+BitmapImage::~BitmapImage()
+{
+    invalidatePlatformData();
+    stopAnimation();
+}
+
+void BitmapImage::destroyDecodedData(bool incremental, bool preserveNearbyFrames)
+{
+    // Destroy the cached images and release them.
+    if (m_frames.size()) {
+        int sizeChange = 0;
+        int frameSize = m_size.width() * m_size.height() * 4;
+        const size_t nextFrame = (preserveNearbyFrames && frameCount()) ? ((m_currentFrame + 1) % frameCount()) : 0;
+        for (unsigned i = incremental ? m_frames.size() - 1 : 0; i < m_frames.size(); i++) {
+            if (m_frames[i].m_frame && (!preserveNearbyFrames || (i != m_currentFrame && i != nextFrame))) {
+                sizeChange -= frameSize;
+                m_frames[i].clear();
+            }
+        }
+
+        // We just always invalidate our platform data, even in the incremental case.
+        // This could be better, but it's not a big deal.
+        m_isSolidColor = false;
+        invalidatePlatformData();
+        
+        if (sizeChange) {
+            m_decodedSize += sizeChange;
+            if (imageObserver())
+                imageObserver()->decodedSizeChanged(this, sizeChange);
+        }
+        
+        if (!incremental) {
+            // Reset the image source, since Image I/O has an underlying cache that it uses
+            // while animating that it seems to never clear.
+#if !PLATFORM(SGL)
+            m_source.clear();
+            m_source.setData(m_data.get(), m_allDataReceived);
+#endif
+        }
+    }
+}
+
+void BitmapImage::cacheFrame(size_t index)
+{
+    size_t numFrames = frameCount();
+    ASSERT(m_decodedSize == 0 || numFrames > 1);
+    
+    if (m_frames.size() < numFrames)
+        m_frames.grow(numFrames);
+
+    m_frames[index].m_frame = m_source.createFrameAtIndex(index);
+    if (numFrames == 1 && m_frames[index].m_frame)
+        checkForSolidColor();
+
+    m_frames[index].m_haveMetadata = true;
+    m_frames[index].m_isComplete = m_source.frameIsCompleteAtIndex(index);
+    if (repetitionCount(false) != cAnimationNone)
+        m_frames[index].m_duration = m_source.frameDurationAtIndex(index);
+    m_frames[index].m_hasAlpha = m_source.frameHasAlphaAtIndex(index);
+
+    int sizeChange;
+    if (index) {
+        IntSize frameSize = m_source.frameSizeAtIndex(index);
+        if (frameSize != m_size)
+            m_hasUniformFrameSize = false;
+        sizeChange = m_frames[index].m_frame ? frameSize.width() * frameSize.height() * 4 : 0;
+    } else
+        sizeChange = m_frames[index].m_frame ? m_size.width() * m_size.height() * 4 : 0;
+
+    if (sizeChange) {
+        m_decodedSize += sizeChange;
+        if (imageObserver())
+            imageObserver()->decodedSizeChanged(this, sizeChange);
+    }
+}
+
+IntSize BitmapImage::size() const
+{
+    if (m_sizeAvailable && !m_haveSize) {
+        m_size = m_source.size();
+        m_haveSize = true;
+    }
+    return m_size;
+}
+
+IntSize BitmapImage::currentFrameSize() const
+{
+    if (!m_currentFrame || m_hasUniformFrameSize)
+        return size();
+    return m_source.frameSizeAtIndex(m_currentFrame);
+}
+
+bool BitmapImage::dataChanged(bool allDataReceived)
+{
+    destroyDecodedData(true);
+    
+    // Feed all the data we've seen so far to the image decoder.
+    m_allDataReceived = allDataReceived;
+    m_source.setData(m_data.get(), allDataReceived);
+    
+    // Clear the frame count.
+    m_haveFrameCount = false;
+
+    m_hasUniformFrameSize = true;
+
+    // Image properties will not be available until the first frame of the file
+    // reaches kCGImageStatusIncomplete.
+    return isSizeAvailable();
+}
+
+size_t BitmapImage::frameCount()
+{
+    if (!m_haveFrameCount) {
+        m_haveFrameCount = true;
+        m_frameCount = m_source.frameCount();
+    }
+    return m_frameCount;
+}
+
+bool BitmapImage::isSizeAvailable()
+{
+    if (m_sizeAvailable)
+        return true;
+
+    m_sizeAvailable = m_source.isSizeAvailable();
+
+    return m_sizeAvailable;
+}
+
+NativeImagePtr BitmapImage::frameAtIndex(size_t index)
+{
+    if (index >= frameCount())
+        return 0;
+
+    if (index >= m_frames.size() || !m_frames[index].m_frame)
+        cacheFrame(index);
+
+    return m_frames[index].m_frame;
+}
+
+bool BitmapImage::frameIsCompleteAtIndex(size_t index)
+{
+    if (index >= frameCount())
+        return true;
+
+    if (index >= m_frames.size() || !m_frames[index].m_haveMetadata)
+        cacheFrame(index);
+
+    return m_frames[index].m_isComplete;
+}
+
+float BitmapImage::frameDurationAtIndex(size_t index)
+{
+    if (index >= frameCount())
+        return 0;
+
+    if (index >= m_frames.size() || !m_frames[index].m_haveMetadata)
+        cacheFrame(index);
+
+    return m_frames[index].m_duration;
+}
+
+bool BitmapImage::frameHasAlphaAtIndex(size_t index)
+{
+    if (index >= frameCount())
+        return true;
+
+    if (index >= m_frames.size() || !m_frames[index].m_haveMetadata)
+        cacheFrame(index);
+
+    return m_frames[index].m_hasAlpha;
+}
+
+int BitmapImage::repetitionCount(bool imageKnownToBeComplete)
+{
+    if ((m_repetitionCountStatus == Unknown) || ((m_repetitionCountStatus == Uncertain) && imageKnownToBeComplete)) {
+        // Snag the repetition count.  If |imageKnownToBeComplete| is false, the
+        // repetition count may not be accurate yet for GIFs; in this case the
+        // decoder will default to cAnimationLoopOnce, and we'll try and read
+        // the count again once the whole image is decoded.
+        m_repetitionCount = m_source.repetitionCount();
+        m_repetitionCountStatus = (imageKnownToBeComplete || m_repetitionCount == cAnimationNone) ? Certain : Uncertain;
+    }
+    return m_repetitionCount;
+}
+
+bool BitmapImage::shouldAnimate()
+{
+    return (repetitionCount(false) != cAnimationNone && !m_animationFinished && imageObserver());
+}
+
+void BitmapImage::startAnimation(bool catchUpIfNecessary)
+{
+    if (m_frameTimer || !shouldAnimate() || frameCount() <= 1)
+        return;
+
+    // Determine time for next frame to start.  By ignoring paint and timer lag
+    // in this calculation, we make the animation appear to run at its desired
+    // rate regardless of how fast it's being repainted.
+    const double currentDuration = frameDurationAtIndex(m_currentFrame);
+    const double time = currentTime();
+    if (m_desiredFrameStartTime == 0) {
+        m_desiredFrameStartTime = time + currentDuration;
+    } else {
+        m_desiredFrameStartTime += currentDuration;
+        // If we're too far behind, the user probably doesn't care about
+        // resyncing and we could burn a lot of time looping through frames
+        // below.  Just reset the timings.
+        if ((time - m_desiredFrameStartTime) > cAnimationResyncCutoff)
+            m_desiredFrameStartTime = time + currentDuration;
+    }
+
+    // Don't advance the animation to an incomplete frame.
+    size_t nextFrame = (m_currentFrame + 1) % frameCount();
+    if (!frameIsCompleteAtIndex(nextFrame))
+        return;
+
+    // Don't advance past the last frame if we haven't decoded the whole image
+    // yet and our repetition count is potentially unset.  The repetition count
+    // in a GIF can potentially come after all the rest of the image data, so
+    // wait on it.
+    if (!m_allDataReceived && repetitionCount(false) == cAnimationLoopOnce && m_currentFrame >= (frameCount() - 1))
+        return;
+
+    // The image may load more slowly than it's supposed to animate, so that by
+    // the time we reach the end of the first repetition, we're well behind.
+    // Clamp the desired frame start time in this case, so that we don't skip
+    // frames (or whole iterations) trying to "catch up".  This is a tradeoff:
+    // It guarantees users see the whole animation the second time through and
+    // don't miss any repetitions, and is closer to what other browsers do; on
+    // the other hand, it makes animations "less accurate" for pages that try to
+    // sync an image and some other resource (e.g. audio), especially if users
+    // switch tabs (and thus stop drawing the animation, which will pause it)
+    // during that initial loop, then switch back later.
+    if (nextFrame == 0 && m_repetitionsComplete == 0 && m_desiredFrameStartTime < time)
+      m_desiredFrameStartTime = time;
+
+    if (!catchUpIfNecessary || time < m_desiredFrameStartTime) {
+        // Haven't yet reached time for next frame to start; delay until then.
+        m_frameTimer = new Timer<BitmapImage>(this, &BitmapImage::advanceAnimation);
+        m_frameTimer->startOneShot(std::max(m_desiredFrameStartTime - time, 0.));
+    } else {
+        // We've already reached or passed the time for the next frame to start.
+        // See if we've also passed the time for frames after that to start, in
+        // case we need to skip some frames entirely.  Remember not to advance
+        // to an incomplete frame.
+        for (size_t frameAfterNext = (nextFrame + 1) % frameCount(); frameIsCompleteAtIndex(frameAfterNext); frameAfterNext = (nextFrame + 1) % frameCount()) {
+            // Should we skip the next frame?
+            double frameAfterNextStartTime = m_desiredFrameStartTime + frameDurationAtIndex(nextFrame);
+            if (time < frameAfterNextStartTime)
+                break;
+
+            // Yes; skip over it without notifying our observers.
+            if (!internalAdvanceAnimation(true))
+                return;
+            m_desiredFrameStartTime = frameAfterNextStartTime;
+            nextFrame = frameAfterNext;
+        }
+
+        // Draw the next frame immediately.  Note that m_desiredFrameStartTime
+        // may be in the past, meaning the next time through this function we'll
+        // kick off the next advancement sooner than this frame's duration would
+        // suggest.
+        if (internalAdvanceAnimation(false)) {
+            // The image region has been marked dirty, but once we return to our
+            // caller, draw() will clear it, and nothing will cause the
+            // animation to advance again.  We need to start the timer for the
+            // next frame running, or the animation can hang.  (Compare this
+            // with when advanceAnimation() is called, and the region is dirtied
+            // while draw() is not in the callstack, meaning draw() gets called
+            // to update the region and thus startAnimation() is reached again.)
+            // NOTE: For large images with slow or heavily-loaded systems,
+            // throwing away data as we go (see destroyDecodedData()) means we
+            // can spend so much time re-decoding data above that by the time we
+            // reach here we're behind again.  If we let startAnimation() run
+            // the catch-up code again, we can get long delays without painting
+            // as we race the timer, or even infinite recursion.  In this
+            // situation the best we can do is to simply change frames as fast
+            // as possible, so force startAnimation() to set a zero-delay timer
+            // and bail out if we're not caught up.
+            startAnimation(false);
+        }
+    }
+}
+
+void BitmapImage::stopAnimation()
+{
+    // This timer is used to animate all occurrences of this image.  Don't invalidate
+    // the timer unless all renderers have stopped drawing.
+    delete m_frameTimer;
+    m_frameTimer = 0;
+}
+
+void BitmapImage::resetAnimation()
+{
+    stopAnimation();
+    m_currentFrame = 0;
+    m_repetitionsComplete = 0;
+    m_desiredFrameStartTime = 0;
+    m_animationFinished = false;
+    int frameSize = m_size.width() * m_size.height() * 4;
+
+    // For extremely large animations, when the animation is reset, we just throw everything away.
+    if (frameCount() * frameSize > cLargeAnimationCutoff)
+        destroyDecodedData();
+}
+
+void BitmapImage::advanceAnimation(Timer<BitmapImage>* timer)
+{
+    internalAdvanceAnimation(false);
+    // At this point the image region has been marked dirty, and if it's
+    // onscreen, we'll soon make a call to draw(), which will call
+    // startAnimation() again to keep the animation moving.
+}
+
+bool BitmapImage::internalAdvanceAnimation(bool skippingFrames)
+{
+    // Stop the animation.
+    stopAnimation();
+    
+    // See if anyone is still paying attention to this animation.  If not, we don't
+    // advance and will remain suspended at the current frame until the animation is resumed.
+    if (!skippingFrames && imageObserver()->shouldPauseAnimation(this))
+        return false;
+
+    m_currentFrame++;
+    if (m_currentFrame >= frameCount()) {
+        ++m_repetitionsComplete;
+        // Get the repetition count again.  If we weren't able to get a
+        // repetition count before, we should have decoded the whole image by
+        // now, so it should now be available.
+        if (repetitionCount(true) && m_repetitionsComplete >= m_repetitionCount) {
+            m_animationFinished = true;
+            m_desiredFrameStartTime = 0;
+            m_currentFrame--;
+            if (skippingFrames) {
+                // Uh oh.  We tried to skip past the end of the animation.  We'd
+                // better draw this last frame.
+                notifyObserverAndTrimDecodedData();
+            }
+            return false;
+        }
+        m_currentFrame = 0;
+    }
+
+    if (!skippingFrames)
+        notifyObserverAndTrimDecodedData();
+
+    return true;
+}
+
+void BitmapImage::notifyObserverAndTrimDecodedData()
+{
+    // Notify our observer that the animation has advanced.
+    imageObserver()->animationAdvanced(this);
+
+    // For large animated images, go ahead and throw away frames as we go to
+    // save footprint.
+    int frameSize = m_size.width() * m_size.height() * 4;
+    if (frameCount() * frameSize > cLargeAnimationCutoff) {
+        // Destroy all of our frames and just redecode every time.  We save the
+        // current frame since we'll need it in draw() anyway.
+        destroyDecodedData(false, true);
+    }
+}
+
+}