quick rendering forest- HOW???

[bluedragon128]

Your idea might work, but the results might not be what you are looking for. Here is a link http://www.cgtalk.com/showthread.php?s=&threadid=74351&highlight=grondore . Hope this might give you an idea or two on how to make a forest seem large yet keeping it small. Another good reference is Shrek, check out the making I believe they talked about adding depth to make the forest look big, without having large render times.

[Konstruct]

sorry, but the link on that thread is dead:shrug:

[dmcgrath]

Link works fine for me. It's a pretty nice idea. Right click and Save As...

[BrainFaucet]

I usually just say "no" to paint FX, but this might be just what the doctor ordered in this case.

[TheGreenGiant]

Hello. I've got a similar question so I'm bumping this thread up. I hope some cool pro can help me out.

Instead of a forest, I'm needing to creat a large field - something like cornfield or just waist high grass

at the moment - there are 2 ways to do it

1) paint fx - I was wondering how good/bad it would look if a polygonal model had to walk through the grass - It's during the day and all so shadow casting isn't something I'll be needing (I think). I'm just a little concerned at how the grass from PFX seems weedy and 2d - does it look any better in motion?

2) PaintFX -- > POLY. I'm doing some trials at the moment but the field that I will need will be huge and I wasn't sure about the highpoly count on the converted PAINTFX grass. The test renders look okay I guess.

3) Modelling individual clumps of grass (that way i can control density and poly count) - And then duplicating it and controlling spread and look with displacement mapping (read this somewhere).

Which is ideal? I'm going to go with option 3) but uurrggh.. / kneels over.

[Kabab]

I was just doing a desert scence with some cactus i want spread randomly.

So i just modeled a cactus and used the paint geometery tool in the bonus tools pack.

Just make your brush size nice and big and set rotation to Y also keep the limit it places pretty low and paint away.

It should create a fairly random spread and with rotate Y your model will face differently.

Try using this tool with 4-5 different models so it doesn't look to repetative.

[TheGreenGiant]

Hi there!

Paint geometry sounds like a ripper of an idea. I thought it should come into play at some point Thanks for that. I guess I have to model grass. / puts that down on list of things to do. :)

* OH, forgot to mention option 4 - if the scene is going to have a huge field - would it be feasible to render the grass in clumps/zones and composite them into the final movie pass? I'm thinking that that is something that will have to be done because render time on the Prarie would otherwise be insanely long - especially if the animation is going to take place on this set.

[mark_wilkins]

for trees in the midground and distance you should consider pre-rendering a few trees with alpha and mapping the 2D images onto planes. You'll get the right kind of movement when you move the camera and it will look great. It will also be very quick interactively and at render time.

-- Mark

[TheGreenGiant]

Hello.

this is related to the earlier post that offered the solution of using the PAINT GEOMETRY tool by KABAB. I used it and the tool is

a) uncontrollable in terms of distribution
b) uncontrollable in terms of geometry sizer determination (I know you can adjust the U+V setting) but it comes out in a very shizo manner - sometimes huge some times tiny.
I am trying to replicate grass ( I modelled about 5 blades and its very low poly) and the tool can go crazy.

I also don't know why it did this but when I try to do the paint geometry tool with polygons, it seems to want to offset the created geometry by some seemingly random distance fromt the reference plane/sphere (I am testing). When I use the tool on a nurbs plane, it does the same offset but most created geometry lands on the same spot.

:thumbsdow

[boraddd]

i did this couple of times for crowd sim shots in the past...
- you`ll create a particle object with all the particles laying on the ground. these particles will represent indivual tree`s or whatever million of objects you need to render.
- add a pp attribute to the particle object and randomly set this attr for each particle.. this will respresent the differnt version of the object you`ll use.(different looking trees for example)
- import all different trees you need to use to the scene and name them properly so you can call their name in a script which we`ll be using later.
- write a preRender mel scripts which depth sorts all the particles, and starting from the furstest away particle it places the object specified to that particles position and renders it. Let say it will render a.tga first. Than b.tga. than comp b.tga over a.tga using a system comp util and copy that comped image as a.tga back again.. Little confusing maybe but you`re simply rendering every object separetly and comping it back to previous image... I prefer calling `shake` in the background to this is comping since its scriptable and fast..

so here is my method...you can render unlimited num of objects without any problem.. it`s also fast(enough)....
if anybody really interested in building such a workflow i can explain further details such as Zdepth and shadow implemantation to this method..

[Konstruct]

yeah that sounds way slick,, I`m having LOTS of issues with my method.

you should explaind more PLEASE, OH, btw, I have rolling hills, will the method still work?

because I`m not about to move each tree up to the terrain level. thats WAY too much work. perhaps maybe you also know a method I could select multiple objects and have them all snap to the serface of a mesh.

Its been a while but I remeber bryce had this featre I`m talking about. so I image maya is MORE than capable.

[antweiler]

konstruct,
for the distribution of your particles, you could run a simulation to make the particles "rain" on your hills. the distribution can be influenced by for example turbulence field. Then use the particle instancer for your low rez trees.
did you give the new pfx forest brushes a try ? i didnt try seriously, but they look quite cool, editing is easy, but it seems you need some tweaking for the desired look.

antweiler

[Kabab]

Originally posted by TheGreenGiant
Hello.

this is related to the earlier post that offered the solution of using the PAINT GEOMETRY tool by KABAB. I used it and the tool is

a) uncontrollable in terms of distribution
b) uncontrollable in terms of geometry sizer determination (I know you can adjust the U+V setting) but it comes out in a very shizo manner - sometimes huge some times tiny.
I am trying to replicate grass ( I modelled about 5 blades and its very low poly) and the tool can go crazy.

I also don't know why it did this but when I try to do the paint geometry tool with polygons, it seems to want to offset the created geometry by some seemingly random distance fromt the reference plane/sphere (I am testing). When I use the tool on a nurbs plane, it does the same offset but most created geometry lands on the same spot.

:thumbsdow
If you are painting on a poly surface it will need UV maps, i just used the automatic UV map setting.

Make sure you freeze transformations on both objects before you start.

It works perfectly for me.

[Duncan]

Note that one can easily adjust the tessellation of paint effects created in pfx to poly. Open the window:
paintEffects->meshQuality
and select the meshes. The relevant brush parameters that affect the triangle count will appear in the window. (You need to have construction history on when doing pfx to poly for this to work)

You should be able to get the pfx grass to look pretty good.. the key is in getting the shadow setting right, so that the pfx self shadows. Mid dist maps should be turned off. For better antialiasing turn on oversample in the pfx render globals.

Duncan

[TheGreenGiant]

Thanks guys for the replies. It's not like its going unappreciated. I"ll try some of the stuff later tonight. Gotta do some more sketches tonight. ;D

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