What's a good foliage work flow?

[visualride]

Ok, I've read most of the posts on what softwares to use for trees and plants, but I'm trying to nail down the best workflow to have 30-60 trees, and 500-1000 plants in a 20 house developement animated fly through that I'm doing. I have Onyx tree and plants, but they seem to lack the density and realizm that I'm seeing with the Xfrog trees and plants. I'm using image planes facing the camera for the distant plants now, and some proxy 3d Onyx trees.

If I convince my company to buy Xfrog, I'm wondering if I should be rendering out Xfrog trees and plants as matte objects first to keep my scene managable (under 1 mil. polys) and composite later. I haven't used matte compositing before, and after reading another persons posts about their problems with this, I'm hesitant, and running out of time for experimenting.

I know that opacity mapped trees take a long time with Vray, but has anyone had any luck creating a matte in Vray, then rendering with scanline the trees and comping later? How would you deal with reflections of these objects?

I've seen lots of great stills, and tests using lots of trees and plants here, but still haven't read about a comprehensive solution to a big animated project. Since I'm not using any animated scenery such as cars and people, I'm pre rendering the ir maps. I have 30 pc's here at my disposal at night, so the render times can be up to an hour per frame (720x480).

[jow]

visualride, ive never tried the comping idea,the only way you can use that many trees and plants is to go down the proxy route.
if you going to buy xfrog3.5 you could modify the plant leafs so instead of being a single square plane with an opacity map,you could give the leaf a physical shape (bit like how onyxtrees are done) then add a map with out opacity.

with opacity-


geometry-


i didnt spend much time on this so the geometry one could look alot better! but you get the idea and the time!!!!

joconnell has made a script to do the same thing,see his post-
http://www.chaosgroup.com/forum/phpB...er=asc&start=0

hope this helps,abit...

[visualride]

Thanks for your demonstration jow. It looks like you got most of the way with the geometry swapping. Just need some texture tweeking, and leaf shape editing.

I forgot to mention that I've been using joconnell's script with some success. It's been great so far, but I still run into massive geometry trees(100k+ poly's).

I was also wondering if anyone here has had much success with LOD (level of detail) swapping. I haven't checked in a while, but I'm sure there must be some great scripts out there to swap out geometry based on how close to the camera it gets. The trick then would be to animate the visibility of the incoming and outgoing trees, and match the geometry well. In my experience, at least with scanline rendering, animating visiblity is very slow. How is it with VRay?

[RErender]

In my experience, at least with scanline rendering, animating visiblity is very slow. How is it with VRay?

Don't even think about it...

[jow]

no worries,if you are thinking of buying xfrog this is the way to go i think.
i spent only 5 mins in xfrog changing the square plane to a basic shape.this would work well for background plants as the ploy count is only up 10k (from 28k to38k).
you might need to edit the leaf texture in PS so that it bleed over the edges,the leaf i used was the same map with a green background(the wrong green) -


then just use opacity mapped trees for the foreground.....

[DJ-Studd]

I wonder how it would go in terms of render time if you use a basic shape like jow's, but also applied an opacity map. Would it be quicker, given that it's not applying the opacity map for such a large surface area of the plane, or would the geometry AND the opacity offset any speed gains?

-- DJ

[jow]

DJ-Studd-just tried it, 4m 52s.so abit quicker but doesnt look to nice..

[visualride]

Thanks for the time trial jow. Does Xfrog have a leaf editor to update all the leaf geometry? I haven't closely examined the differences between Xfrog trees and Onyx tree's, but if you aren't using opacity mapping with Xfrog, aren't you basically getting what you could get with Onyx tree, or is the basic tree structure better in Xfrog? Are the parameters easier to edit?

Back to my overall question of compete workflow of a large exterior developement, are there any guys from the larger studios out there holding out? When I'm working on my projects, sometimes the drafters around me at work hear me complain about not being able to easily render these massive scenes and say "You need more computer power like they have at the movie studios". I know that the they have similar computers like me at the studios, but their processes are split up, so that layers of trees, layers of plants and layers of other objects can be rendered separately and composited later by a compositor that just does that. This takes more time, but it allows for reasonable geometry sizes, and control of the individual elements. I've always worked solo in all relms of 3D so I haven't had the chance to get at how the large processes work. Anyone know if Gnomon, or any one else has such a tutorial video on matte's, and compositing at the quality of Chris's Vray tut's? I'm done rambling now.

[jow]

Does Xfrog have a leaf editor to update all the leaf geometry?

sort of,you can choose between a simple square or triangle,or you can have a spline shape that you edit.

I haven't closely examined the differences between Xfrog trees and Onyx tree's, but if you aren't using opacity mapping with Xfrog, aren't you basically getting what you could get with Onyx tree, or is the basic tree structure better in Xfrog?

i havnt used onyxtree so can't comment,but what ive seen of onyx it looks very similar.the good thing being that the model make up is going to be the same between the opacity mapped and the geometry trees. so if say you need to change a tree from opacity to geom.,just swap the maps.

Are the parameters easier to edit?

it takes some getting use to....