Corn troubles

Slum

Hi everyone.

I'm having a bit of an issue. The project I'm working on requires me to make a field of corn (and possibly wheat). It's using the Half-Life 2 Source engine, so it has to be a fairly detailed, so I can't just go full on alpha planes. I was thinking individual models could work, but they'd have to be really low poly since there would be a lot of them.

The way I'm doing it right now is this:
The stalk is made of two alpha planes crossed in the center in a + shape. Then the leaves are all alpha planes and the corn husk is a 5 sided cylinder. It's currently at about 120 tris, but that's way too much considering I need an entire field of them.

I was thinking I could do them it row sets of LoD. The player can not actually go inside the field and it is only visible from one angle (i.e. player is trapped by one side of the field, the outer boundaries of the field aren't accessable) The front rows would be the 120 tri models, middle rows would be lower poly and the back rows would be pure alpha planes.

Any suggestions on other techniques or ideas?

Eric Chadwick

Sounds like a good plan to me. If the player can walk right up the the first row, then you'd want those to be the most detailed.

I would test the framerate with a quick set of models, see what wiggle-room I had for a higher triangle count.

What about wind or subtle motion? Might be cool.

You might also try optimizing the rendering by creating the whole field, then reordering all the triangles into same-shader lumps... detach/re-attach all the alpha-d tris, etc. Might save some framerate.

CheeseOnToast

This might be impractical and expensive, but I've seen a tree made with particle emitters (for the leaves at any rate). Particles might work for the distant rows, and could be given some subtle movement too.

Zergxes

Is there a way to instance low count geometry as a particle within the engine?

Scott Ruggels

If you can, Limit the approachess folks can take towards the fielsd, ic you can you need only to detail the first couple rows of corn, then do flats with normal maps and alphas. Talk to your coder about making those "Face the camera" type billboards. Wo like only 3 or 4 rows in would be full geometry. If the unfortunate situation occurs tha the player are supposed to enter the corn field, like a corn maze, well your approach will still work, but see what limitation upon the "player" can be worked out.

Scott