Using 2D Objects for HUGE populations

[moodflow]

Hi All,

I tried rendering a very large valley with pine trees, and to get the scale I needed, it required so many individual trees, it crashed my system (2GB of RAM).

Does anyone know of a way to use 2D "billboard" objects with a tree image, rather than higher polygon 3D models?  If so, do you have an .tgo or .obj file to post?

Otherwise, I think I could figure it out using Wings3D.

[old_blaggard]

TG2 doesn't automatically billboard yet.  If you're doing a large-scale image, you could try decreasing the quality of the trees to low.  That should save you some RAM and some render time.

[bigben]

On models i've tested, using low quality removes the leaves which is a bit obvious.  Do you have any masking to restrict the tree population to just within the frame?

Otherwise, all you need is a vertical square object with an image texture.  In the population you can adjust the size to match your texture image  and the rotation to match your camera angle.  You could create a texture image of your object from a render of a single tree from the side.

[cbalaskas]

Hey I used a 2d card setup in one of my "cracked face" images. Heres the tgo. Enjoy.

[bigben]

You might want to zip that file. TGOs are technically binary files even though some of the node network may be legible in a text editor.

[moodflow]

Thanks for the file cbalaskas!  This should work well for those trees WAY off in the distance.

[moodflow]

Hi cbalaskas,

Would you be able to post a zipped version of the file?  I tested the version you posted and it refers to a shader that doesn't exist.  When I try to compensate and add my own, it still doesn't work.

I also tried creating one using planes, but to no avail.

Many thanks!

[cbalaskas]

Here you go. Let me know if you have any more problems.

<EDIT> Just downloaded and opened it in TG2 myself with no problems. You should be good to go. You'll need an color and opacity image. You could render out some tree from Bryce or wherever with similiar lighting as your scene, and then set the diffuse to 0 and luminosity to 1 so they don't look so obvious. Combined with a few "hero" trees up front, the scene should be totally convincing.

[moodflow]

Many thanks!  Got it working perfectly.  Did you build this file? 

[bigben]

Here you go. Let me know if you have any more problems.

<EDIT> Just downloaded and opened it in TG2 myself with no problems. You should be good to go. You'll need an color and opactity image. You could render out some tree from Bryce or wherever...

or in TG2

Add a tree, zoom to tree, disable planet and render. Explore temp files and you have an image and an alpha channel. You can always combine them into the one TIF file, using the alpha for the transparency.

[cbalaskas]

moodflow: yeah I threw it together in Wings3D a while back. You could add another two planes at an angle for a little more realism.

bigben: very true, but i was thinking of Bryce's (frustrating) tree builder tool. Any 3D program and object model would work. Currently I'm trying to build a desert bush model for my lifeless canyons.

[bigben]

The main reason I mentioned a method for TG2 is that  you can  generate an image with whatever modifications you make to the tree... e.g. autumn leaves/ removing leaves, and generating the alpha is automatic.

I've had a quick play and found that the transparency worked but the trees were white.  Checked the object settings and the luminosity is set to 1 for both faces... and one had a reflectivity of 1. Once fixed, it was working nicely. I'll definitely add this to my tree quality vs. distance setup.  I've previously struck a barrier around 20km with a 90 degree fov using medium quality trees but this should help to smash this.

Many thanks for the object.

[moodflow]

Yes, this file was a breakthrough on one of my images that required massive forestry off in the distance!  I used a 2D image of a real tree with alpha channel, but it could also be done with a 2d tree image rendered in any app, provided lighting is accounted for.

I used to use 2D billboards like this in Bryce, but had to add them manually (very thankfull for cut/paste and grouping!), but always hoped I could do populations with the fractal and distrubution constraints Terragen had since this is more realistic and easier.  Its now possible and the game is ON!

Additionally, you can use these for up close items as well, as long as they are quite small.

Over the past few years, I've been accumulating 2D images (with alpha) of trees and foliage, and more than half I created manually (with lots of work).  Alot of matte painters use them as well.

[cbalaskas]

Oops forgot about the luminosity I used an image of a tree for diffuse, and then the same image as luminosity and reduceed diffuse to zero. This avoids tell tale shadows, but in the distance its barely perceptable. We should do a post of 2d plants and objects we have the right to distribute. That would be a great resource!

[bigben]

Oops forgot about the luminosity I used an image of a tree for diffuse, and then the same image as luminosity and reduceed diffuse to zero. This avoids tell tale shadows, but in the distance its barely perceptable. We should do a post of 2d plants and objects we have the right to distribute. That would be a great resource!

Ahhh... that might be useful with certain lighting angles. I'll give it a try

Maybe people could include a 2D image of any TGO tree models they distribute as well.  That could also be used to provide a thumbnail preview for links to the download

I have had another thought of how I could use this...  I'm preparing a grid to use as a rough ruler to help position other objects/cameras more accurately (with less trial and error) around an object. e.g. placing a camera at the tail of a plane and then calculating a path for the camera based on the path/orientation of the plane. 

I'm assuming the two faces are square?