WebCore/ChangeLog

2008-06-18  Peter Kasting  <zerodpx@gmail.com>

        Reviewed by NOBODY (OOPS!).

        https://bugs.webkit.org/show_bug.cgi?id=19663

        Account for paint lag when animating images.

        * platform/graphics/BitmapImage.cpp:

        (WebCore::BitmapImage::BitmapImage):

        (WebCore::BitmapImage::startAnimation):

        (WebCore::BitmapImage::advanceAnimation):

        * platform/graphics/BitmapImage.h:

2008-06-18  Timothy Hatcher  <timothy@apple.com>

        Add a script build phase to remove the WebKit.qrc file from

34652

WebCore/platform/graphics/BitmapImage.cpp

#include "ImageObserver.h"

#include "IntRect.h"

#include "PlatformString.h"

34#include "SystemTime.h"

#include "Timer.h"

#include <wtf/Vector.h>

#include "MIMETypeRegistry.h"

@@BitmapImage::BitmapImage(ImageObserver*

    , m_frameTimer(0)

    , m_repetitionCount(0)

    , m_repetitionsComplete(0)

52 , m_lastAnimationFrameTime(0)

    , m_isSolidColor(false)

    , m_animatingImageType(true)

    , m_animationFinished(false)

@@void BitmapImage::startAnimation()

    if (!m_allDataReceived && m_repetitionCount == cAnimationLoopOnce && m_currentFrame >= (frameCount() - 1))

        return;

    // Calculate desired delay.  frameDurationAtIndex() tells us how long the

    // current frame wants to be visible.  Reduce this by the amount of time

    // we've spent drawing since we advanced to this frame, so that the

    // animation appears to run at the correct framerate regardless of drawing

    // lag.  (In the common case, the drawing lag for the next frame will be

    // similar, and thus the frame will actually be visible for almost the exact

    // same amount of time it requests to be visible.)

    double delay = frameDurationAtIndex(m_currentFrame);

    if (m_lastAnimationFrameTime != 0)

      delay -= (currentTime() - m_lastAnimationFrameTime);

    if (delay < 0)

      delay = 0;

235250 m_frameTimer = new Timer<BitmapImage>(this, &BitmapImage::advanceAnimation);

236 m_frameTimer->startOneShot(~~frameDurationAtIndex(m_currentFrame)~~);

251 m_frameTimer->startOneShot(delay);

}

void BitmapImage::stopAnimation()

@@void BitmapImage::advanceAnimation(Timer

    // We do not advance the animation explicitly.  We rely on a subsequent draw of the image

    // to force a request for the next frame via startAnimation().  This allows images that move offscreen while

    // scrolling to stop animating (thus saving memory from additional decoded frames and

302 // CPU time spent doing the decoding).

    // CPU time spent doing the decoding).  However, this drawing will take nonzero time.  So,

    // save the current time, so that if we do want to draw another frame, we can delay it

    // relative to right now, rather than relative to when the drawing actually finishes.  This

    // makes the animation speed not vary based on our drawing lag.

    m_lastAnimationFrameTime = currentTime();

}

}

34652

WebCore/platform/graphics/BitmapImage.h

@@protected:

    Timer<BitmapImage>* m_frameTimer;

    int m_repetitionCount; // How many total animation loops we should do.

    int m_repetitionsComplete;  // How many repetitions we've finished.

186 double m_lastAnimationFrameTime; // The system time at which we finished advancing the last animation frame.

#if PLATFORM(MAC)

    mutable RetainPtr<NSImage> m_nsImage; // A cached NSImage of frame 0. Only built lazily if someone actually queries for one.

34652