baking dense vine geometry into lo-poly mesh

azryth

Hello, I am creating a interior scene that I want to be overrun with vines. The vine geometry is waayyy too dense, and I can't figure out how to (if possible) turn all the dense vine geometry into a single flat plane with a texture map [color, light, and shadow all baked in]. That way i can offset the textured plane from the wall and hopefully have it look like vines from afar.

furthermore, and I really hope this is possible, i have also generated vines all over props and objects inside the scene such as boulders on the ground, a spherical space capsule(the main prop). These all look great with the vines growing all over them, BUT i want to use the existing lo-poly geometry of the original props as a surface to bake the vine geometry on. That way I would have the original lo-poly props... and duplicate the prop's geometry to use as a shell, which would have the viny texture w/alpha applied to it and slightly extruded so that you could see through the vine texture to the original prop beneath.

Is there a way, instead of using a camera, to bake based on geometry normals? How would I be able to bake those dense textured vines into the lo-poly props underneath?


This is a real puzzler, so thank you greatly if you take a crack at it!

EarthQuake

The same way you'de bake a normalmap from a highres mesh to a lowres mesh, just project it onto the low with render-to-texture in max, or xnormal or maya or whatever. And you should jsut get an alpha channel in on of these maps to use as a mask in your engine.

Rick Stirling

You should also be able to bake your colour/spec/AO maps as well.

Are you planning a more geo based system for up close views, or will people never get that close?

azryth

hmm... I guess I didnt think to use a normal map because the vine geometry is so much more complex and random than the flat faceted lo-poly geometry I was aiming for... but Its worth a try with alpha also applied... which operation (in maya 8.5)would I use to get the color, lighting, and alpha information aside from the normal map or is it all the same operation??

azryth

and no, the goal is a realistic look from a medium distance, not too close

JKMakowka

http://boards.polycount.net/showflat.php?Cat=0&Number=171381&an=&page=0&vc=1

Have a look at the link above! He basicly did exactly what you are trying to do right?

Edit: you have to scroll down a bit for the flats of the normal mapped vines.

Xenobond

Here's what I would do. I'd make a tiling vine texture baked down from some of the hipoly vines you've got going. You'd have to play with the alpha a bit to get this to work. To avoid sorting problems in game, I'd have the material for the vines set to be on alphatest. Then you'd use the alpha of the texture combined with vertex alpha to modify the coverage of the vines. I'd love to be able to show you a screengrab or other example image for ya, but I'm on vacation, and no real access to 2d/3d apps.