/// <summary>
/// 回收所有场景元素到对象池并清空集合。
/// </summary>
public override void Clear()
{
for (int i = 0; i < elements.Count; i++)
{
SceneElementPool.Delete(elements[i]);
}
elements.Clear();
elementCoordinates.Clear();
}
protected override void UpdateCulling(ALayerCamera layerCamera)
{
if (elementCoordinates.Count == 0)
{
return;
}
// 获取可见的最近和最远场景元素的索引值
int nearElementIndex;
int farElementIndex;
GetVisibleElementsRange(layerCamera, out nearElementIndex, out farElementIndex);
// 设置可视范围内的元素为可见
for (int i = nearElementIndex; i <= farElementIndex; i++)
{
if (!elements[i].IsVisible)
{
elements[i].OnBecameVisible(layerCamera);
}
}
// 回收身后的场景元素
if (positiveDirection == RelativeDirection.Positive)
{
int index = 0;
while (index < nearElementIndex)
{
SceneElementPool.Delete(elements[0]);
elements.RemoveAt(0);
elementCoordinates.RemoveAt(0);
index += 1;
}
}
else
{
int index = elements.Count - 1;
while (index > farElementIndex)
{
SceneElementPool.Delete(elements[index]);
elements.RemoveAt(index);
elementCoordinates.RemoveAt(index);
index -= 1;
}
}
}