int nbTilesWidth = tileBounds.width();
int nbTilesHeight = tileBounds.height();
- int lastTileX = tileBounds.fRight - 1;
- int lastTileY = tileBounds.fBottom - 1;
-
// Expand number of tiles to allow tiles outside of viewport to be prepared for
// smoother scrolling.
int nTilesToPrepare = nbTilesWidth * nbTilesHeight;
int expandY = m_glWebViewState->expandedTileBoundsY();
firstTileX -= expandX;
- lastTileX += expandX;
nbTilesWidth += expandX * 2;
firstTileY -= expandY;
- lastTileY += expandY;
nbTilesHeight += expandY * 2;
}
// crop the prepared region to the contents of the base layer
float maxWidthTiles = m_glWebViewState->baseContentWidth() * m_scale / TilesManager::tileWidth();
float maxHeightTiles = m_glWebViewState->baseContentHeight() * m_scale / TilesManager::tileHeight();
- firstTileX = std::max(0, firstTileX);
- firstTileY = std::max(0, firstTileY);
- lastTileX = std::min(lastTileX, static_cast<int>(ceilf(maxWidthTiles)) - 1);
- lastTileY = std::min(lastTileY, static_cast<int>(ceilf(maxHeightTiles)) - 1);
+
+ // adjust perimeter to not go outside base content bounds
+ if (firstTileX < 0) {
+ nbTilesWidth += firstTileX;
+ firstTileX = 0;
+ }
+ if (firstTileY < 0) {
+ nbTilesHeight += firstTileY;
+ firstTileY = 0;
+ }
+ nbTilesWidth = std::min(nbTilesWidth, static_cast<int>(ceilf(maxWidthTiles)) - firstTileX);
+ nbTilesHeight = std::min(nbTilesHeight, static_cast<int>(ceilf(maxHeightTiles)) - firstTileY);
// check against corrupted scale values giving bad height/width (use float to avoid overflow)
float numTiles = static_cast<float>(nbTilesHeight) * static_cast<float>(nbTilesWidth);