How do I delete section of terrain for tunnel?

#1 The empty tool for the terrain is not currently exposed to the interface, you should see it back again in upcoming betas.

#2 Wow, I thought that were not posible with this terrain system. Very good!

#3 We are in Beta 2 now. Is there any update on which beta this will be put in at?

#4 I'll make sure its in for beta 3.... it just got burried under some higher priorities for beta 2.

#5 Instead of deleting polygons, wouldn't it be easier to use an additional alpha mask with alpha test on and 50% alpha ref? It would prevent LOD problems with the holes and allow holes that don't look so square due to the bilinear filtering. It would also be easier to integrate into the editor, since the functionality for painting terrain masks is already there.

#6 @Playlore
That assumes there is a higher resolution texture defining where holes in the terrain are.... and there isn't. You don't want to add a 4096x4096 texture just for defining a hole or two in your terrain... its a huge waste of video memory.

If in a future release we support material layer resolutions different from the base geometry then we could consider that approch, but i don't think it will work for collision.

The current implementation encodes the empty squares into the vertex data, so it works visually and with collision correctly. It also works with the shadow rendering without the need to sample from an alpha mask texture.

#7 Somehow, I completely forgot about video memory usage! If only video cards supported 1-bit textures...