bool BaseLayerAndroid::prepareBasePictureInGL(SkRect& viewport, float scale,
double currentTime)
{
ZoomManager* zoomManager = m_state->zoomManager();
bool goingDown = m_state->goingDown();
bool goingLeft = m_state->goingLeft();
const SkIRect& viewportTileBounds = m_state->viewportTileBounds();
XLOG("drawBasePicture, TX: %d, TY: %d scale %.2f", viewportTileBounds.fLeft,
viewportTileBounds.fTop, scale);
// Query the resulting state from the zoom manager
bool prepareNextTiledPage = zoomManager->needPrepareNextTiledPage();
// Display the current page
TiledPage* tiledPage = m_state->frontPage();
TiledPage* nextTiledPage = m_state->backPage();
tiledPage->setScale(zoomManager->currentScale());
// Let's prepare the page if needed so that it will start painting
if (prepareNextTiledPage) {
nextTiledPage->setScale(scale);
m_state->setFutureViewport(viewportTileBounds);
// ignore dirtiness return value since while zooming we repaint regardless
nextTiledPage->updateTileDirtiness(viewportTileBounds);
nextTiledPage->prepare(goingDown, goingLeft, viewportTileBounds,
TiledPage::VisibleBounds);
// Cancel pending paints for the foreground page
TilesManager::instance()->removePaintOperationsForPage(tiledPage, false);
}
// If we fired a request, let's check if it's ready to use
if (zoomManager->didFireRequest()) {
if (nextTiledPage->swapBuffersIfReady(viewportTileBounds,
zoomManager->futureScale()))
zoomManager->setReceivedRequest(); // transition to received request state
}
float transparency = 1;
bool doZoomPageSwap = false;
// If the page is ready, display it. We do a short transition between
// the two pages (current one and future one with the new scale factor)
if (zoomManager->didReceivedRequest()) {
float nextTiledPageTransparency = 1;
m_state->resetFrameworkInval();
zoomManager->processTransition(currentTime, scale, &doZoomPageSwap,
&nextTiledPageTransparency, &transparency);
nextTiledPage->prepareForDrawGL(nextTiledPageTransparency, viewportTileBounds);
}
const SkIRect& preZoomBounds = m_state->preZoomBounds();
bool zooming = ZoomManager::kNoScaleRequest != zoomManager->scaleRequestState();
if (doZoomPageSwap) {
zoomManager->setCurrentScale(scale);
m_state->swapPages();
}
bool needsRedraw = zooming;
// if applied invals mark tiles dirty, need to redraw
needsRedraw |= tiledPage->updateTileDirtiness(preZoomBounds);
// paint what's needed unless we're zooming, since the new tiles won't
// be relevant soon anyway
if (!zooming)
tiledPage->prepare(goingDown, goingLeft, preZoomBounds,
TiledPage::ExpandedBounds);
XLOG("scrolling %d, zooming %d, needsRedraw %d",
scrolling, zooming, needsRedraw);
// prefetch in the nextTiledPage if unused by zooming (even if not scrolling
// since we want the tiles to be ready before they're needed)
bool usePrefetchPage = !zooming;
nextTiledPage->setIsPrefetchPage(usePrefetchPage);
if (usePrefetchPage) {
// if the non-prefetch page isn't missing tiles, don't bother drawing
// prefetch page
bool drawPrefetchPage = tiledPage->hasMissingContent(preZoomBounds);
prefetchBasePicture(viewport, scale, nextTiledPage, drawPrefetchPage);
}
tiledPage->prepareForDrawGL(transparency, preZoomBounds);
return needsRedraw;
}
