/**
* Merge a sublayer with another sublayer below it in the stack
* Note: the result layer will conserve the given id
* Return true if success or false if layer isn't found or doesn't have a layer under it in the stack
*
* @param integer $layerId
*
* @return boolean
*/
public function mergeDown($layerId)
{
// if the layer exists in document
if ($this->isLayerInIndex($layerId)) {
$layerLevel = $this->getLayerLevel($layerId);
$layerPositions = $this->getLayerPositions($layerId);
$layer = $this->getLayer($layerId);
$layerWidth = $layer->getWidth();
$layerHeight = $layer->getHeight();
$layerPositionX = $this->layerPositions[$layerId]["x"];
$layerPositionY = $this->layerPositions[$layerId]["y"];
if ($layerLevel > 1) {
$underLayerId = $this->layerLevels[$layerLevel - 1];
$underLayer = $this->getLayer($underLayerId);
$underLayerWidth = $underLayer->getWidth();
$underLayerHeight = $underLayer->getHeight();
$underLayerPositionX = $this->layerPositions[$underLayerId]["x"];
$underLayerPositionY = $this->layerPositions[$underLayerId]["y"];
$totalWidthLayer = $layerWidth + $layerPositionX;
$totalHeightLayer = $layerHeight + $layerPositionY;
$totalWidthUnderLayer = $underLayerWidth + $underLayerPositionX;
$totalHeightUnderLayer = $underLayerHeight + $underLayerPositionY;
$minLayerPositionX = $layerPositionX;
if ($layerPositionX > $underLayerPositionX) {
$minLayerPositionX = $underLayerPositionX;
}
$minLayerPositionY = $layerPositionY;
if ($layerPositionY > $underLayerPositionY) {
$minLayerPositionY = $underLayerPositionY;
}
if ($totalWidthLayer > $totalWidthUnderLayer) {
$layerTmpWidth = $totalWidthLayer - $minLayerPositionX;
} else {
$layerTmpWidth = $totalWidthUnderLayer - $minLayerPositionX;
}
if ($totalHeightLayer > $totalHeightUnderLayer) {
$layerTmpHeight = $totalHeightLayer - $minLayerPositionY;
} else {
$layerTmpHeight = $totalHeightUnderLayer - $minLayerPositionY;
}
$layerTmp = new self(array("width" => $layerTmpWidth, "height" => $layerTmpHeight));
$layerTmp->addLayer(1, $underLayer, $underLayerPositionX - $minLayerPositionX, $underLayerPositionY - $minLayerPositionY);
$layerTmp->addLayer(2, $layer, $layerPositionX - $minLayerPositionX, $layerPositionY - $minLayerPositionY);
// Update layers
$layerTmp->mergeAll();
$this->layers[$underLayerId] = clone $layerTmp;
$this->layerPositions[$underLayerId]["x"] = $minLayerPositionX;
$this->layerPositions[$underLayerId]["y"] = $minLayerPositionX;
} else {
$layerTmp = new self(array("imageVar" => $this->image));
$layerTmp->addLayer(1, $layer, $layerPositionX, $layerPositionY);
// Update background image
$this->image = $layerTmp->getResult();
}
unset($layerTmp);
// Remove the merged layer from the stack
$this->remove($layerId);
return true;
}
return false;
}
