void TiledPage::prepareRow(bool goingLeft, int tilesInRow, int firstTileX, int y, const SkIRect& tileBounds)
{
for (int i = 0; i < tilesInRow; i++) {
int x = firstTileX;
// If we are goingLeft, we want to schedule the tiles starting from the
// right (and to the left if not). This is because tiles are appended to
// the list and the texture uploader goes through the set front to back.
if (goingLeft)
x += (tilesInRow - 1) - i;
else
x += i;
BaseTile* currentTile = 0;
BaseTile* availableTile = 0;
for (int j = 0; j < m_baseTileSize; j++) {
BaseTile& tile = m_baseTiles[j];
if (tile.x() == x && tile.y() == y) {
currentTile = &tile;
break;
}
if (!availableTile || (tile.drawCount() < availableTile->drawCount()))
availableTile = &tile;
}
if (!currentTile && availableTile) {
XLOG("STEALING tile %d, %d (draw count %llu) for tile %d, %d",
availableTile->x(), availableTile->y(), availableTile->drawCount(), x, y);
availableTile->discardTextures(); // don't wait for textures to be stolen
currentTile = availableTile;
}
if (!currentTile) {
XLOG("ERROR: No tile available for tile %d %d", x, y);
}
if (currentTile) {
currentTile->setGLWebViewState(m_glWebViewState);
currentTile->setPage(this);
currentTile->setContents(this, x, y, m_scale);
// TODO: move below (which is largely the same for layers / tiled
// page) into prepare() function
// ensure there is a texture associated with the tile and then check to
// see if the texture is dirty and in need of repainting
if (currentTile->isDirty() || !currentTile->frontTexture())
currentTile->reserveTexture();
if (currentTile->backTexture()
&& currentTile->isDirty()
&& !currentTile->isRepaintPending()) {
PaintTileOperation *operation = new PaintTileOperation(currentTile);
TilesManager::instance()->scheduleOperation(operation);
}
}
}
}
void TilesProfiler::nextTile(BaseTile& tile, float scale, bool inView)
{
if (!m_enabled || (m_records.size() > MAX_PROF_FRAMES) || (m_records.size() == 0))
return;
bool isReady = tile.isTileReady();
int left = tile.x() * TilesManager::tileWidth();
int top = tile.y() * TilesManager::tileWidth();
int right = left + TilesManager::tileWidth();
int bottom = top + TilesManager::tileWidth();
if (inView) {
if (isReady)
m_goodTiles++;
else
m_badTiles++;
}
m_records.last().append(TileProfileRecord(
left, top, right, bottom,
scale, isReady, (int)tile.drawCount()));
XLOG("adding tile %d %d %d %d, scale %f", left, top, right, bottom, scale);
}
BaseTileTexture* TilesManager::getAvailableTexture(BaseTile* owner)
{
android::Mutex::Autolock lock(m_texturesLock);
// Sanity check that the tile does not already own a texture
if (owner->backTexture() && owner->backTexture()->owner() == owner) {
XLOG("same owner (%d, %d), getAvailableBackTexture(%x) => texture %x",
owner->x(), owner->y(), owner, owner->backTexture());
if (owner->isLayerTile())
m_availableTilesTextures.remove(m_availableTilesTextures.find(owner->backTexture()));
else
m_availableTextures.remove(m_availableTextures.find(owner->backTexture()));
return owner->backTexture();
}
WTF::Vector<BaseTileTexture*>* availableTexturePool;
if (owner->isLayerTile()) {
availableTexturePool = &m_availableTilesTextures;
} else {
availableTexturePool = &m_availableTextures;
}
// The heuristic for selecting a texture is as follows:
// 1. Skip textures currently being painted, they can't be painted while
// busy anyway
// 2. If a tile isn't owned, break with that one
// 3. Don't let tiles acquire their front textures
// 4. If we find a tile in the same page with a different scale,
// it's old and not visible. Break with that one
// 5. Otherwise, use the least recently prepared tile, but ignoring tiles
// drawn in the last frame to avoid flickering
BaseTileTexture* farthestTexture = 0;
unsigned long long oldestDrawCount = getDrawGLCount() - 1;
const unsigned int max = availableTexturePool->size();
for (unsigned int i = 0; i < max; i++) {
BaseTileTexture* texture = (*availableTexturePool)[i];
BaseTile* currentOwner = static_cast<BaseTile*>(texture->owner());
if (texture->busy()) {
// don't bother, since the acquire() will likely fail
continue;
}
if (!currentOwner) {
// unused texture! take it!
farthestTexture = texture;
break;
}
if (currentOwner == owner) {
// Don't let a tile acquire its own front texture, as the
// acquisition logic doesn't handle that
continue;
}
if (currentOwner->painter() == owner->painter() && texture->scale() != owner->scale()) {
// if we render the back page with one scale, then another while
// still zooming, we recycle the tiles with the old scale instead of
// taking ones from the front page
farthestTexture = texture;
break;
}
unsigned long long textureDrawCount = currentOwner->drawCount();
if (oldestDrawCount > textureDrawCount) {
farthestTexture = texture;
oldestDrawCount = textureDrawCount;
}
}
if (farthestTexture) {
BaseTile* previousOwner = static_cast<BaseTile*>(farthestTexture->owner());
if (farthestTexture->acquire(owner)) {
if (previousOwner) {
previousOwner->removeTexture(farthestTexture);
XLOG("%s texture %p stolen from tile %d, %d for %d, %d, drawCount was %llu (now %llu)",
owner->isLayerTile() ? "LAYER" : "BASE",
farthestTexture, previousOwner->x(), previousOwner->y(),
owner->x(), owner->y(),
oldestDrawCount, getDrawGLCount());
}
availableTexturePool->remove(availableTexturePool->find(farthestTexture));
return farthestTexture;
}
} else {
if (owner->isLayerTile()) {
// couldn't find a tile for a layer, layers shouldn't request redraw
// TODO: once we do layer prefetching, don't set this for those
// tiles
m_layerTexturesRemain = false;
}
}
XLOG("Couldn't find an available texture for %s tile %x (%d, %d) out of %d available",
owner->isLayerTile() ? "LAYER" : "BASE",
owner, owner->x(), owner->y(), max);
#ifdef DEBUG
printTextures();
#endif // DEBUG
return 0;
}