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Cocefi
04-28-2003, 04:12 AM
Hello there,

I'm having some difficulty in modeling low poly trees (the normal kind, not pines). The tree will be used for a 3rd person view game. I need some tips/tricks on how I should place the leaves on top of the tree.

For the leaves, I created a flat polygon, UVmapped and textured it. Then I place it randomly on top of the tree. The problem is that it doesn't look very "natural" (either the shape doesn't look right or at certain angles, the leaf isn't dense enough).

I'll post up a pic my feeble attempt later as I don't have it with me now.

Any tips, tricks or tutorial will be great. Thank! :beer:

Jboy
04-28-2003, 05:51 AM
dude don't make a single leaf, make a clump of them, or even make all the foliage as one big polygon. hell, the whole tree could be one poly with a transparancy map if it's not important.

Artician
04-28-2003, 07:23 AM
Trees can be really tough. Here's the best technique I've learned when creating trees of that kind.

Model the trunk, and several (usually 2 or 3) "main" branches. I usually spend about 2/3rds to 3/4ths the total poly count on these.
The remainder of the tree, and the way you get a good feeling of upper volume of twigs and leaves, is by using flat planes and a single texturemap with alpha. Try to create some natural looking depth to your map, but not too much since most of this will come from the geometry of the model. Personally I always make certain the texture itself has one obvious medium-sized branch coming from the edge of your plane. Then, when placing the planes on the rest of the geometry, I line this up so that the texture blends with the main geometry, and it looks like another natural extension of the tree itself.
Copy the planes around your model, make certain you give their placement a somewhat chaotic look to them to make it appear more natural. Position them at odd angles, don't be afraid to cross two planes through each other, and remember you're creating more volume than individual details.
Something I usually try to stick with is that I never position any of the planar branches at an angle towards the ground. Almost always the branches are positioned in the upper 180 degree region. This isn't wrong, I've seen lots of fantastic in-game examples where people did just that, but I find the results to be much more natural looking if I allow everything to flow upward.

If you want to check out some references on your own, I highly recommend the NOLF2 demo. The japanese village in the demo has some of the best in-game trees ever. You won't regret it.

Cocefi
04-28-2003, 07:49 AM
Jboy:
Ah, I was using a clump of leaves as texture actually. Sorry for not being clear ealier.

Artician:
Many thanks for the info! I'll give it another go later tonight and maybe post some result tomorrow. :wip:

RustyJar
04-28-2003, 11:15 PM
Deciduous trees can really be a pain to make. It took us a couple attempts at it before we came up with a good system. What we're doing now for trees is to model the trunk and main brances as normal, but make the leaf clumps a particle system (with a corresponding texture of a clump of leaves). Then all I have to do as the artist is place a node where I want the particle system to be emitted from, set some of the values in the particle editor, and poof... a nice randomly generated tree. Of course this only works if you have an engine that supports particles like this, but its a fast way to knock out a lot of different looking trees with very little work. And as an added bonus, you can assign a "sway" value to the particle emitter to make the leaves rustle in the wind.

Cocefi
04-29-2003, 02:28 AM
RustyJar:
Using a particle system for the leaves is a great idea! Unfortunately, our game engine at the moment is pretty basic (no lighting and all). Maybe I could try doing the particle trick in the 3d app and export the "frozen" object out. Thanks for the info! :)



And here's the result of yesterday's attempt. Sorry about the small image... 30kb is pretty small... :surprised

Both of the pic is of the same tree but on a different viewing angle. The shape on the first angle looks pretty Ok, but the second one doesn't look that good. I'm going to try to do a better texture for the leaves tonight and tweak the tree polygons a bit more.

What do you think? Any suggestions on how to improve on it?
Thanks! :bounce:

Dhin
04-29-2003, 11:16 AM
Twist and bend the trunk alittle more. I needs a more organic chaos look. Plus a good technique for "leaf clumps" if you have the time in to build and texture a high poly leaf and twig, clone the leaf and attach it to the twig making a realistic or stylized looking branch. Find a good angle that looks natual, now render it to an image. Now you have a nice leaf clump texture, create an alpha map of it and you now have low poly leaves, map them to a plain and check that they look right, tweak where needed and rerender until you like it. It isn't the easiest way of doing it, but it has a nice result.

Rivendale
04-29-2003, 12:25 PM
Hi, here's a method I've been using to get some volume into the foliage. I place the alphamapped planes in a kinda spherical or cylindrical shape, clone them scale them down a bit, and then rotate and tweak. You can see what I mean in the image below.
Hope it helps any

JahnkeKong
04-29-2003, 05:15 PM
Just wanted to say this is a very informative thread!! :thumbsup: thanks for all the info :)

RustyJar
04-29-2003, 05:18 PM
Whats the face count of that tree Rivendale?

Rivendale
04-29-2003, 09:44 PM
RustyJar- The trunk is 368 polys and the foliage is 124.

Cocefi
05-02-2003, 02:32 AM
I would like to thank everyone for their help and advice on making the tree. After a few more tries, I've finally completed my tree and although it's not superb, I'm pretty satisfied with it. :cool:

Here's a few things I learned during the creation process:

- don't use leaf textures that have small contrasting details. It'll look very "noisy" when it's viewed from afar.

- to make the tree look "balanced", I place 1/3 of the leaves by hand and duplicated it around the other 2/3 with a bit of offset.

Plus other great things that I've learned from this thread. Thanks again! :wavey:

And here's a shot at my final tree (295 tris, including both sides of the leaves)...

oxygen_77
05-02-2003, 01:11 PM
CCF,

Did you purchase the texture for the leaves? I am currently working on a project and while I've found some resources for free tree and branch images, I would be thankful for any other links you could provide. Also can you post a wireframe image of your finished tree? Thanks!

S. J. Tubbrit
05-02-2003, 02:34 PM
Hope This Helps : -

Tree Tutorial (http://www.steven-tubbrit.pwp.blueyonder.co.uk/Tutorials/Tutorial_01.htm)

EricChadwick
05-02-2003, 04:43 PM
Here's a bunch of copyright-free freebies from USGS. Varying quality though.
http://rmmcnt7.cr.usgs.gov/ecl/help/required.htm

Marlin Studios has a pretty good product if you're ready to pay.
http://www.marlinstudios.com/products/vtf/vtf.htm

oxygen_77
05-02-2003, 06:21 PM
S. J. Tubbrit and posm,

Thanks for the links!!! I've seen the Marlin link, but can't afford such expensive textures...

SyDemon
05-03-2003, 04:04 AM
The trees are very well done! I love the texture's greed, so tranquil and natural looking!

Cocefi
05-03-2003, 06:50 AM
Hi hi,

For the leaves, I roughly traced over a picture to get a bushy-shaped mask, then overlay some leafy textures on top of it and finish it off with a few colour touch ups.

I'll post up the mask later so you can you use it to make your own leaves. :)

And here's the wireframe pic... :wip:

BoromirNo1
05-03-2003, 01:06 PM
This guy has made some trees for Neverwinter Nights.
http://www.i-nation.co.uk/
screenshots only.

Cocefi
05-04-2003, 03:41 PM
Here's the leaf mask I did for my tree (although it was slightly modified to fit the 256x256 texture size on the tree). :)

Feel free to use it to create your own leaves.

oxygen_77
05-04-2003, 04:30 PM
That's very nice of you! Thanks!!!

DFGFX
05-07-2003, 01:25 AM
Sorry guys but since i dun understand i would like to ask you a favor... Could you all please post 3dsmax files of your trees?

three
05-07-2003, 06:37 AM
I found a link for a tree tutorial regarding NeverWinter Nights, 3DSMAX. Somewhere on the NWN vault... can't seem to find it now though... I'll keep looking. If I find it again I'll holler :)

Nyceane
08-07-2003, 07:59 PM
2 polygon...

can't move =/

im making a project with like almost 100 trees...

and with many other things

is there anyway i can get a tree done within 50 poly? 100 some polygon per tree is too much, with tree with wind moving...

oxygen_77
08-07-2003, 08:23 PM
It shouldn't be too difficult to use the tutorial I will supply and make a 50poly tree. You'll probably want to get the TreeCage plugin from Flay.com to make the base of the tree (trunk, roots, branches) and then use the tutorial here:

http://www.animationartist.com/2000/Tutorials/LWTrees/lwtrees.html#

to make the leaves. Or instead you could further save poly's by making a planar leaf object instead of the spherical one listed in the tutorial. Then as the final thing you could run qemLOSS 3 on the tree to further reduce polys. I used this method in a scene with over 1000 trees... It worked quite well.

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