how to check if an entity is on the edge ?

Hi,
How would I ckeck to see if an entity is on the edge of the screen or camera view?

For example if I have an entity walking on a 3d plane and I would want the camera to follow the entity/or zoom out when the entity is still on the screen/in camera view but just about to clip the edge of the screen/camera ?

Thanks for you help.

you could use CameraProject with entityx, entityy, entityz methods and check it with graphicswidth, graphicsheight

You can also try linepick to send out feelers ahead.