Remove TiledBacking / TileCache code

Source/WebCore/platform/graphics/TiledBackingStore.cpp

Index: Source/WebCore/platform/graphics/TiledBackingStore.cpp
diff --git a/Source/WebCore/platform/graphics/TiledBackingStore.cpp b/Source/WebCore/platform/graphics/TiledBackingStore.cpp
deleted file mode 100644
index 790945b90385d56079f365eceb636497f4d1cb37..0000000000000000000000000000000000000000
--- a/Source/WebCore/platform/graphics/TiledBackingStore.cpp
+++ /dev/null
@@ -1,598 +0,0 @@
-/*
- Copyright (C) 2010-2012 Nokia Corporation and/or its subsidiary(-ies)
- 
- This library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Library General Public
- License as published by the Free Software Foundation; either
- version 2 of the License, or (at your option) any later version.
- 
- This library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- Library General Public License for more details.
- 
- You should have received a copy of the GNU Library General Public License
- along with this library; see the file COPYING.LIB.  If not, write to
- the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA.
- */
-
-#include "config.h"
-#include "TiledBackingStore.h"
-
-#if USE(TILED_BACKING_STORE)
-
-#include "GraphicsContext.h"
-#include "TiledBackingStoreClient.h"
-
-namespace WebCore {
-
-static const int defaultTileDimension = 512;
-
-static IntPoint innerBottomRight(const IntRect& rect)
-{
-    // Actually, the rect does not contain rect.maxX(). Refer to IntRect::contain.
-    return IntPoint(rect.maxX() - 1, rect.maxY() - 1);
-}
-
-TiledBackingStore::TiledBackingStore(TiledBackingStoreClient* client, PassOwnPtr<TiledBackingStoreBackend> backend)
-    : m_client(client)
-    , m_backend(backend)
-    , m_tileBufferUpdateTimer(this, &TiledBackingStore::tileBufferUpdateTimerFired)
-    , m_backingStoreUpdateTimer(this, &TiledBackingStore::backingStoreUpdateTimerFired)
-    , m_tileSize(defaultTileDimension, defaultTileDimension)
-    , m_coverAreaMultiplier(2.0f)
-    , m_contentsScale(1.f)
-    , m_pendingScale(0)
-    , m_commitTileUpdatesOnIdleEventLoop(false)
-    , m_contentsFrozen(false)
-    , m_supportsAlpha(false)
-    , m_pendingTileCreation(false)
-{
-}
-
-TiledBackingStore::~TiledBackingStore()
-{
-}
-
-void TiledBackingStore::setTileSize(const IntSize& size)
-{
-    m_tileSize = size;
-    m_tiles.clear();
-    startBackingStoreUpdateTimer();
-}
-
-void TiledBackingStore::setTrajectoryVector(const FloatPoint& trajectoryVector)
-{
-    m_pendingTrajectoryVector = trajectoryVector;
-    m_pendingTrajectoryVector.normalize();
-}
-
-void TiledBackingStore::coverWithTilesIfNeeded()
-{
-    IntRect visibleRect = this->visibleRect();
-    IntRect rect = mapFromContents(m_client->tiledBackingStoreContentsRect());
-
-    bool didChange = m_trajectoryVector != m_pendingTrajectoryVector || m_visibleRect != visibleRect || m_rect != rect;
-    if (didChange || m_pendingTileCreation)
-        createTiles();
-}
-
-void TiledBackingStore::invalidate(const IntRect& contentsDirtyRect)
-{
-    IntRect dirtyRect(mapFromContents(contentsDirtyRect));
-
-    // Only iterate on the part of the rect that we know we might have tiles.
-    IntRect coveredDirtyRect = intersection(dirtyRect, m_keepRect);
-    Tile::Coordinate topLeft = tileCoordinateForPoint(coveredDirtyRect.location());
-    Tile::Coordinate bottomRight = tileCoordinateForPoint(innerBottomRight(coveredDirtyRect));
-
-    for (int yCoordinate = topLeft.y(); yCoordinate <= bottomRight.y(); ++yCoordinate) {
-        for (int xCoordinate = topLeft.x(); xCoordinate <= bottomRight.x(); ++xCoordinate) {
-            RefPtr<Tile> currentTile = tileAt(Tile::Coordinate(xCoordinate, yCoordinate));
-            if (!currentTile)
-                continue;
-            // Pass the full rect to each tile as coveredDirtyRect might not
-            // contain them completely and we don't want partial tile redraws.
-            currentTile->invalidate(dirtyRect);
-        }
-    }
-
-    startTileBufferUpdateTimer();
-}
-
-void TiledBackingStore::updateTileBuffers()
-{
-    if (m_contentsFrozen)
-        return;
-
-    m_client->tiledBackingStorePaintBegin();
-
-    Vector<IntRect> paintedArea;
-    Vector<RefPtr<Tile> > dirtyTiles;
-    TileMap::iterator end = m_tiles.end();
-    for (TileMap::iterator it = m_tiles.begin(); it != end; ++it) {
-        if (!it->value->isDirty())
-            continue;
-        dirtyTiles.append(it->value);
-    }
-
-    if (dirtyTiles.isEmpty()) {
-        m_client->tiledBackingStorePaintEnd(paintedArea);
-        return;
-    }
-
-    // FIXME: In single threaded case, tile back buffers could be updated asynchronously 
-    // one by one and then swapped to front in one go. This would minimize the time spent
-    // blocking on tile updates.
-    unsigned size = dirtyTiles.size();
-    for (unsigned n = 0; n < size; ++n) {
-        Vector<IntRect> paintedRects = dirtyTiles[n]->updateBackBuffer();
-        paintedArea.append(paintedRects);
-        dirtyTiles[n]->swapBackBufferToFront();
-    }
-
-    m_client->tiledBackingStorePaintEnd(paintedArea);
-}
-
-void TiledBackingStore::paint(GraphicsContext* context, const IntRect& rect)
-{
-    context->save();
-
-    // Assumes the backing store is painted with the scale transform applied.
-    // Since tile content is already scaled, first revert the scaling from the painter.
-    context->scale(FloatSize(1.f / m_contentsScale, 1.f / m_contentsScale));
-
-    IntRect dirtyRect = mapFromContents(rect);
-
-    Tile::Coordinate topLeft = tileCoordinateForPoint(dirtyRect.location());
-    Tile::Coordinate bottomRight = tileCoordinateForPoint(innerBottomRight(dirtyRect));
-
-    for (int yCoordinate = topLeft.y(); yCoordinate <= bottomRight.y(); ++yCoordinate) {
-        for (int xCoordinate = topLeft.x(); xCoordinate <= bottomRight.x(); ++xCoordinate) {
-            Tile::Coordinate currentCoordinate(xCoordinate, yCoordinate);
-            RefPtr<Tile> currentTile = tileAt(currentCoordinate);
-            if (currentTile && currentTile->isReadyToPaint())
-                currentTile->paint(context, dirtyRect);
-            else {
-                IntRect tileRect = tileRectForCoordinate(currentCoordinate);
-                IntRect target = intersection(tileRect, dirtyRect);
-                if (target.isEmpty())
-                    continue;
-                m_backend->paintCheckerPattern(context, FloatRect(target));
-            }
-        }
-    }
-    context->restore();
-}
-
-IntRect TiledBackingStore::visibleRect() const
-{
-    return mapFromContents(m_client->tiledBackingStoreVisibleRect());
-}
-
-void TiledBackingStore::setContentsScale(float scale)
-{
-    if (m_pendingScale == m_contentsScale) {
-        m_pendingScale = 0;
-        return;
-    }
-    m_pendingScale = scale;
-    if (m_contentsFrozen)
-        return;
-    commitScaleChange();
-}
-
-void TiledBackingStore::commitScaleChange()
-{
-    m_contentsScale = m_pendingScale;
-    m_pendingScale = 0;
-    m_tiles.clear();
-    coverWithTilesIfNeeded();
-}
-
-double TiledBackingStore::tileDistance(const IntRect& viewport, const Tile::Coordinate& tileCoordinate) const
-{
-    if (viewport.intersects(tileRectForCoordinate(tileCoordinate)))
-        return 0;
-
-    IntPoint viewCenter = viewport.location() + IntSize(viewport.width() / 2, viewport.height() / 2);
-    Tile::Coordinate centerCoordinate = tileCoordinateForPoint(viewCenter);
-
-    return std::max(abs(centerCoordinate.y() - tileCoordinate.y()), abs(centerCoordinate.x() - tileCoordinate.x()));
-}
-
-// Returns a ratio between 0.0f and 1.0f of the surface of contentsRect covered by rendered tiles.
-float TiledBackingStore::coverageRatio(const WebCore::IntRect& contentsRect) const
-{
-    IntRect dirtyRect = mapFromContents(contentsRect);
-    float rectArea = dirtyRect.width() * dirtyRect.height();
-    float coverArea = 0.0f;
-
-    Tile::Coordinate topLeft = tileCoordinateForPoint(dirtyRect.location());
-    Tile::Coordinate bottomRight = tileCoordinateForPoint(innerBottomRight(dirtyRect));
-
-    for (int yCoordinate = topLeft.y(); yCoordinate <= bottomRight.y(); ++yCoordinate) {
-        for (int xCoordinate = topLeft.x(); xCoordinate <= bottomRight.x(); ++xCoordinate) {
-            Tile::Coordinate currentCoordinate(xCoordinate, yCoordinate);
-            RefPtr<Tile> currentTile = tileAt(currentCoordinate);
-            if (currentTile && currentTile->isReadyToPaint()) {
-                IntRect coverRect = intersection(dirtyRect, currentTile->rect());
-                coverArea += coverRect.width() * coverRect.height();
-            }
-        }
-    }
-    return coverArea / rectArea;
-}
-
-bool TiledBackingStore::visibleAreaIsCovered() const
-{
-    IntRect boundedVisibleContentsRect = intersection(m_client->tiledBackingStoreVisibleRect(), m_client->tiledBackingStoreContentsRect());
-    return coverageRatio(boundedVisibleContentsRect) == 1.0f;
-}
-
-void TiledBackingStore::createTiles()
-{
-    // Guard here as as these can change before the timer fires.
-    if (isBackingStoreUpdatesSuspended())
-        return;
-
-    // Update our backing store geometry.
-    const IntRect previousRect = m_rect;
-    m_rect = mapFromContents(m_client->tiledBackingStoreContentsRect());
-    m_trajectoryVector = m_pendingTrajectoryVector;
-    m_visibleRect = visibleRect();
-
-    if (m_rect.isEmpty()) {
-        setCoverRect(IntRect());
-        setKeepRect(IntRect());
-        return;
-    }
-
-    /* We must compute cover and keep rects using the visibleRect, instead of the rect intersecting the visibleRect with m_rect,
-     * because TBS can be used as a backing store of GraphicsLayer and the visible rect usually does not intersect with m_rect.
-     * In the below case, the intersecting rect is an empty.
-     *
-     *  +---------------+
-     *  |               |
-     *  |   m_rect      |
-     *  |       +-------|-----------------------+
-     *  |       | HERE  |  cover or keep        |
-     *  +---------------+      rect             |
-     *          |         +---------+           |
-     *          |         | visible |           |
-     *          |         |  rect   |           |
-     *          |         +---------+           |
-     *          |                               |
-     *          |                               |
-     *          +-------------------------------+
-     *
-     * We must create or keep the tiles in the HERE region.
-     */
-
-    IntRect coverRect;
-    IntRect keepRect;
-    computeCoverAndKeepRect(m_visibleRect, coverRect, keepRect);
-
-    setCoverRect(coverRect);
-    setKeepRect(keepRect);
-
-    if (coverRect.isEmpty())
-        return;
-
-    // Resize tiles at the edge in case the contents size has changed, but only do so
-    // after having dropped tiles outside the keep rect.
-    bool didResizeTiles = false;
-    if (previousRect != m_rect)
-        didResizeTiles = resizeEdgeTiles();
-
-    // Search for the tile position closest to the viewport center that does not yet contain a tile.
-    // Which position is considered the closest depends on the tileDistance function.
-    double shortestDistance = std::numeric_limits<double>::infinity();
-    Vector<Tile::Coordinate> tilesToCreate;
-    unsigned requiredTileCount = 0;
-
-    // Cover areas (in tiles) with minimum distance from the visible rect. If the visible rect is
-    // not covered already it will be covered first in one go, due to the distance being 0 for tiles
-    // inside the visible rect.
-    Tile::Coordinate topLeft = tileCoordinateForPoint(coverRect.location());
-    Tile::Coordinate bottomRight = tileCoordinateForPoint(innerBottomRight(coverRect));
-    for (int yCoordinate = topLeft.y(); yCoordinate <= bottomRight.y(); ++yCoordinate) {
-        for (int xCoordinate = topLeft.x(); xCoordinate <= bottomRight.x(); ++xCoordinate) {
-            Tile::Coordinate currentCoordinate(xCoordinate, yCoordinate);
-            if (tileAt(currentCoordinate))
-                continue;
-            ++requiredTileCount;
-            double distance = tileDistance(m_visibleRect, currentCoordinate);
-            if (distance > shortestDistance)
-                continue;
-            if (distance < shortestDistance) {
-                tilesToCreate.clear();
-                shortestDistance = distance;
-            }
-            tilesToCreate.append(currentCoordinate);
-        }
-    }
-
-    // Now construct the tile(s) within the shortest distance.
-    unsigned tilesToCreateCount = tilesToCreate.size();
-    for (unsigned n = 0; n < tilesToCreateCount; ++n) {
-        Tile::Coordinate coordinate = tilesToCreate[n];
-        setTile(coordinate, m_backend->createTile(this, coordinate));
-    }
-    requiredTileCount -= tilesToCreateCount;
-
-    // Paint the content of the newly created tiles or resized tiles.
-    if (tilesToCreateCount || didResizeTiles)
-        updateTileBuffers();
-
-    // Re-call createTiles on a timer to cover the visible area with the newest shortest distance.
-    m_pendingTileCreation = requiredTileCount;
-    if (m_pendingTileCreation) {
-        if (!m_commitTileUpdatesOnIdleEventLoop) {
-            m_client->tiledBackingStoreHasPendingTileCreation();
-            return;
-        }
-
-        static const double tileCreationDelay = 0.01;
-        startBackingStoreUpdateTimer(tileCreationDelay);
-    }
-}
-
-void TiledBackingStore::adjustForContentsRect(IntRect& rect) const
-{
-    IntRect bounds = m_rect;
-    IntSize candidateSize = rect.size();
-
-    rect.intersect(bounds);
-
-    if (rect.size() == candidateSize)
-        return;
-
-    /*
-     * In the following case, there is no intersection of the contents rect and the cover rect.
-     * Thus the latter should not be inflated.
-     *
-     *  +---------------+
-     *  |   m_rect      |
-     *  +---------------+
-     *
-     *          +-------------------------------+
-     *          |          cover rect           |
-     *          |         +---------+           |
-     *          |         | visible |           |
-     *          |         |  rect   |           |
-     *          |         +---------+           |
-     *          +-------------------------------+
-     */
-    if (rect.isEmpty())
-        return;
-
-    // Try to create a cover rect of the same size as the candidate, but within content bounds.
-    int pixelsCovered = candidateSize.width() * candidateSize.height();
-
-    if (rect.width() < candidateSize.width())
-        rect.inflateY(((pixelsCovered / rect.width()) - rect.height()) / 2);
-    if (rect.height() < candidateSize.height())
-        rect.inflateX(((pixelsCovered / rect.height()) - rect.width()) / 2);
-
-    rect.intersect(bounds);
-}
-
-void TiledBackingStore::computeCoverAndKeepRect(const IntRect& visibleRect, IntRect& coverRect, IntRect& keepRect) const
-{
-    coverRect = visibleRect;
-    keepRect = visibleRect;
-
-    // If we cover more that the actual viewport we can be smart about which tiles we choose to render.
-    if (m_coverAreaMultiplier > 1) {
-        // The initial cover area covers equally in each direction, according to the coverAreaMultiplier.
-        coverRect.inflateX(visibleRect.width() * (m_coverAreaMultiplier - 1) / 2);
-        coverRect.inflateY(visibleRect.height() * (m_coverAreaMultiplier - 1) / 2);
-        keepRect = coverRect;
-
-        if (m_trajectoryVector != FloatPoint::zero()) {
-            // A null trajectory vector (no motion) means that tiles for the coverArea will be created.
-            // A non-null trajectory vector will shrink the covered rect to visibleRect plus its expansion from its
-            // center toward the cover area edges in the direction of the given vector.
-
-            // E.g. if visibleRect == (10,10)5x5 and coverAreaMultiplier == 3.0:
-            // a (0,0) trajectory vector will create tiles intersecting (5,5)15x15,
-            // a (1,0) trajectory vector will create tiles intersecting (10,10)10x5,
-            // and a (1,1) trajectory vector will create tiles intersecting (10,10)10x10.
-
-            // Multiply the vector by the distance to the edge of the cover area.
-            float trajectoryVectorMultiplier = (m_coverAreaMultiplier - 1) / 2;
-
-            // Unite the visible rect with a "ghost" of the visible rect moved in the direction of the trajectory vector.
-            coverRect = visibleRect;
-            coverRect.move(coverRect.width() * m_trajectoryVector.x() * trajectoryVectorMultiplier,
-                           coverRect.height() * m_trajectoryVector.y() * trajectoryVectorMultiplier);
-
-            coverRect.unite(visibleRect);
-        }
-        ASSERT(keepRect.contains(coverRect));
-    }
-
-    adjustForContentsRect(coverRect);
-
-    // The keep rect is an inflated version of the cover rect, inflated in tile dimensions.
-    keepRect.unite(coverRect);
-    keepRect.inflateX(m_tileSize.width() / 2);
-    keepRect.inflateY(m_tileSize.height() / 2);
-    keepRect.intersect(m_rect);
-
-    ASSERT(coverRect.isEmpty() || keepRect.contains(coverRect));
-}
-
-bool TiledBackingStore::isBackingStoreUpdatesSuspended() const
-{
-    return m_contentsFrozen;
-}
-
-bool TiledBackingStore::isTileBufferUpdatesSuspended() const
-{
-    return m_contentsFrozen;
-}
-
-bool TiledBackingStore::resizeEdgeTiles()
-{
-    bool wasResized = false;
-    Vector<Tile::Coordinate> tilesToRemove;
-    TileMap::iterator end = m_tiles.end();
-    for (TileMap::iterator it = m_tiles.begin(); it != end; ++it) {
-        Tile::Coordinate tileCoordinate = it->value->coordinate();
-        IntRect tileRect = it->value->rect();
-        IntRect expectedTileRect = tileRectForCoordinate(tileCoordinate);
-        if (expectedTileRect.isEmpty())
-            tilesToRemove.append(tileCoordinate);
-        else if (expectedTileRect != tileRect) {
-            it->value->resize(expectedTileRect.size());
-            wasResized = true;
-        }
-    }
-    unsigned removeCount = tilesToRemove.size();
-    for (unsigned n = 0; n < removeCount; ++n)
-        removeTile(tilesToRemove[n]);
-    return wasResized;
-}
-
-void TiledBackingStore::setKeepRect(const IntRect& keepRect)
-{
-    // Drop tiles outside the new keepRect.
-
-    FloatRect keepRectF = keepRect;
-
-    Vector<Tile::Coordinate> toRemove;
-    TileMap::iterator end = m_tiles.end();
-    for (TileMap::iterator it = m_tiles.begin(); it != end; ++it) {
-        Tile::Coordinate coordinate = it->value->coordinate();
-        FloatRect tileRect = it->value->rect();
-        if (!tileRect.intersects(keepRectF))
-            toRemove.append(coordinate);
-    }
-    unsigned removeCount = toRemove.size();
-    for (unsigned n = 0; n < removeCount; ++n)
-        removeTile(toRemove[n]);
-
-    m_keepRect = keepRect;
-}
-
-void TiledBackingStore::removeAllNonVisibleTiles()
-{
-    IntRect boundedVisibleRect = mapFromContents(intersection(m_client->tiledBackingStoreVisibleRect(), m_client->tiledBackingStoreContentsRect()));
-    setKeepRect(boundedVisibleRect);
-}
-
-PassRefPtr<Tile> TiledBackingStore::tileAt(const Tile::Coordinate& coordinate) const
-{
-    return m_tiles.get(coordinate);
-}
-
-void TiledBackingStore::setTile(const Tile::Coordinate& coordinate, PassRefPtr<Tile> tile)
-{
-    m_tiles.set(coordinate, tile);
-}
-
-void TiledBackingStore::removeTile(const Tile::Coordinate& coordinate)
-{
-    m_tiles.remove(coordinate);
-}
-
-IntRect TiledBackingStore::mapToContents(const IntRect& rect) const
-{
-    return enclosingIntRect(FloatRect(rect.x() / m_contentsScale,
-        rect.y() / m_contentsScale,
-        rect.width() / m_contentsScale,
-        rect.height() / m_contentsScale));
-}
-
-IntRect TiledBackingStore::mapFromContents(const IntRect& rect) const
-{
-    return enclosingIntRect(FloatRect(rect.x() * m_contentsScale,
-        rect.y() * m_contentsScale,
-        rect.width() * m_contentsScale,
-        rect.height() * m_contentsScale));
-}
-
-IntRect TiledBackingStore::tileRectForCoordinate(const Tile::Coordinate& coordinate) const
-{
-    IntRect rect(coordinate.x() * m_tileSize.width(),
-                 coordinate.y() * m_tileSize.height(),
-                 m_tileSize.width(),
-                 m_tileSize.height());
-
-    rect.intersect(m_rect);
-    return rect;
-}
-
-Tile::Coordinate TiledBackingStore::tileCoordinateForPoint(const IntPoint& point) const
-{
-    int x = point.x() / m_tileSize.width();
-    int y = point.y() / m_tileSize.height();
-    return Tile::Coordinate(std::max(x, 0), std::max(y, 0));
-}
-
-void TiledBackingStore::startTileBufferUpdateTimer()
-{
-    if (!m_commitTileUpdatesOnIdleEventLoop)
-        return;
-
-    if (m_tileBufferUpdateTimer.isActive() || isTileBufferUpdatesSuspended())
-        return;
-    m_tileBufferUpdateTimer.startOneShot(0);
-}
-
-void TiledBackingStore::tileBufferUpdateTimerFired(Timer<TiledBackingStore>*)
-{
-    ASSERT(m_commitTileUpdatesOnIdleEventLoop);
-    updateTileBuffers();
-}
-
-void TiledBackingStore::startBackingStoreUpdateTimer(double interval)
-{
-    if (!m_commitTileUpdatesOnIdleEventLoop)
-        return;
-
-    if (m_backingStoreUpdateTimer.isActive() || isBackingStoreUpdatesSuspended())
-        return;
-    m_backingStoreUpdateTimer.startOneShot(interval);
-}
-
-void TiledBackingStore::backingStoreUpdateTimerFired(Timer<TiledBackingStore>*)
-{
-    ASSERT(m_commitTileUpdatesOnIdleEventLoop);
-    createTiles();
-}
-
-void TiledBackingStore::setContentsFrozen(bool freeze)
-{
-    if (m_contentsFrozen == freeze)
-        return;
-
-    m_contentsFrozen = freeze;
-
-    // Restart the timers. There might be pending invalidations that
-    // were not painted or created because tiles are not created or
-    // painted when in frozen state.
-    if (m_contentsFrozen)
-        return;
-    if (m_pendingScale)
-        commitScaleChange();
-    else {
-        startBackingStoreUpdateTimer();
-        startTileBufferUpdateTimer();
-    }
-}
-
-void TiledBackingStore::setSupportsAlpha(bool a)
-{
-    if (a == m_supportsAlpha)
-        return;
-    m_supportsAlpha = a;
-    invalidate(m_rect);
-}
-
-}
-
-#endif