void Start ()
{
mRoot = NGUITools.FindInParents<UIRoot>(gameObject);
mNeedsHalfPixelOffset = (Application.platform == RuntimePlatform.WindowsPlayer ||
Application.platform == RuntimePlatform.WindowsWebPlayer ||
Application.platform == RuntimePlatform.WindowsEditor);
// Only DirectX 9 needs the half-pixel offset
if (mNeedsHalfPixelOffset) mNeedsHalfPixelOffset = (SystemInfo.graphicsShaderLevel < 40);
if (uiCamera == null) uiCamera = NGUITools.FindCameraForLayer(gameObject.layer);
Update();
}