C++ TileLayer::isEmpty方法代码示例

void BucketFillTool::tilePositionChanged(const QPoint &tilePos)
{
    if (mStamp.isEmpty())
        return;

    bool shiftPressed = QApplication::keyboardModifiers() & Qt::ShiftModifier;
    bool fillRegionChanged = false;

    // Make sure that a tile layer is selected
    TileLayer *tileLayer = currentTileLayer();
    if (!tileLayer)
        return;

    // todo: When there are multiple variations, it would make sense to choose
    // random variations while filling. When the variations have different
    // sizes, probably the bounding box of all variations should be used.
    Map *variation = mStamp.randomVariation();
    TileLayer *stampLayer = static_cast<TileLayer*>(variation->layerAt(0));

    // Skip filling if the stamp is empty
    if (!stampLayer || stampLayer->isEmpty())
        return;

    TilePainter regionComputer(mapDocument(), tileLayer);
    // If the stamp is a single tile, ignore it when making the region
    if (stampLayer->width() == 1 && stampLayer->height() == 1 && !shiftPressed &&
            stampLayer->cellAt(0, 0) == regionComputer.cellAt(tilePos.x(),
                                                              tilePos.y()))
        return;

    // This clears the connections so we don't get callbacks
    clearConnections(mapDocument());

    // Optimization: we don't need to recalculate the fill area
    // if the new mouse position is still over the filled region
    // and the shift modifier hasn't changed.
    if (!mFillRegion.contains(tilePos) || shiftPressed != mLastShiftStatus || mIsRandom) {

        // Clear overlay to make way for a new one
        clearOverlay();

        // Cache information about how the fill region was created
        mLastShiftStatus = shiftPressed;

        // Get the new fill region
        if (!shiftPressed) {
            // If not holding shift, a region is generated from the current pos
            mFillRegion = regionComputer.computePaintableFillRegion(tilePos);
        } else {
            // If holding shift, the region is the selection bounds
            mFillRegion = mapDocument()->selectedArea();

            // Fill region is the whole map if there is no selection
            if (mFillRegion.isEmpty())
                mFillRegion = tileLayer->bounds();

            // The mouse needs to be in the region
            if (!mFillRegion.contains(tilePos))
                mFillRegion = QRegion();
        }
        fillRegionChanged = true;
    }

    // Ensure that a fill region was created before making an overlay layer
    if (mFillRegion.isEmpty())
        return;

    if (mLastRandomStatus != mIsRandom) {
        mLastRandomStatus = mIsRandom;
        fillRegionChanged = true;
    }

    if (!mFillOverlay) {
        // Create a new overlay region
        const QRect fillBounds = mFillRegion.boundingRect();
        mFillOverlay = SharedTileLayer(new TileLayer(QString(),
                                                     fillBounds.x(),
                                                     fillBounds.y(),
                                                     fillBounds.width(),
                                                     fillBounds.height()));
    }

    // Paint the new overlay
    if (!mIsRandom) {
        if (fillRegionChanged) {
            mMissingTilesets.clear();
            mapDocument()->unifyTilesets(variation, mMissingTilesets);

            TilePainter tilePainter(mapDocument(), mFillOverlay.data());
            tilePainter.drawStamp(stampLayer, mFillRegion);
        }
    } else {
        randomFill(mFillOverlay.data(), mFillRegion);
        fillRegionChanged = true;
    }

    if (fillRegionChanged) {
        // Update the brush item to draw the overlay
        brushItem()->setTileLayer(mFillOverlay);
    }
//.........这里部分代码省略.........