How to culling in postprocess?

Unity Engine
1

Hi,

I want to use “Graphics.DrawMeshNow” to draw some object in my postprocess:

public class PP_Light_Point : MonoBehaviour
{
......
void OnRenderImage(RenderTexture sourceTexture, RenderTexture destTexture)
{
        Camera curCamera = GetComponent<Camera> ();
        UnityEngine.Object[] _Lights = FindObjectsOfType (typeof(Light));
        foreach (UnityEngine.Object obj in _Lights)
        {
              Light lit = obj as Light;
 
              // There need to cull the light is need to DrawMeshNow.
 
              _LightPointMatrial.SetPass(0);
              Matrix4x4 kWorldMat = lit.transform.localToWorldMatrix;
              Graphics.DrawMeshNow(lp.mesh, kWorldMat);
        }
}
......
}

Some lights are out of camera, they need not to draw. So I want to cull the light.
How to do it? Thank you.

2

Some lights are out of camera, they need not to draw.
that is not exactly true: in normal life, even if you are not seeing the sun - you can still see the result of its lighting (i hope that make sense ;-))
anyway, what you describe sounds like frustum culling (with some modifications it can handle even proper light culling).
you can start here
http://www.flipcode.com/archives/Frustum_Culling.shtml
and then google to your heart pleasure