private void RemoveLayer(LayerController layer)
{
int layerId = layer.GetId();
layers.RemoveAt(layerId);
for (int i = layerId; i < LayerCount; i += 1)
{
layers[i].SetId(i);
}
}
internal void SwapLayers(LayerController layer1, LayerController layer2)
{
SwapLayers(layer1.GetId(), layer2.GetId());
}