Masking tree populations by age

[bigben]

This topic started off as a tangent thread in my Growing Leaves post.  http://forums.planetside.co.uk/index.php?topic=5048.msg52231#msg52231

I've restarted it here to  avoid possible confusion between the two topics..

The "problem" is to distribute 3 different tree models of varying age in a relatively realistic manner.  The attached mask demo produces 3 variations of an overall tree distribution for the 3 age groups of trees. It's based on a very loose assumption that older trees will be at a higher density in the centre of the forest, and young trees will be at a higher density at the edges of a forest.

My first test render is actually over a forest as I only previewed the distribution of the old trees.  As it turns out, what I thought would be a field is actually a region of medium-aged trees, with older trees to the left and right.

I'm running another test render showing the edge of a forest

[gregsandor]

Here it is with 3 separate populations each distributed with the clip you set up. 

Bright yellow-green represents young trees, scaled smallest.  Mid green is mature trees, and dark green is old trees.

[bigben]

Here's my last test.  Note this is a very simplified version of the masking model but you can get the general idea. Particularly on the right hand side

[gregsandor]

Looks great.  Is that with the node setup you posted?  Thanks for your help with this.

[bigben]

That's using the same TGD I posted, with a fractal terrain added.

What you may want to try is working on each population individually at first. Adjust the masks/ object spacing until you get the kind of distribution you want... looking at the maximum tree density in particular.  The put the 3 of them together to see what it looks like.

Looking at fairly linear groups of trees may make things a little difficult. You may want to do this in an area where you have a large body of trees.

[gregsandor]

I'm pleased with that result, and now am moving the test clip over to my main Glenfinnan file.  I think the only change I'll make will be to add altitude and slope distribution.  There are some areas of dense forest, but they are distant.

[gregsandor]

Here's the node setup:

Is there any way to use one object file to feed each of these sections?  I think not since each is scaled and textured differently.  It seems it would be more efficient to use the same geometry only once and send it to be scaled and textured independently.

[bigben]

You'd need separate objects for each pop'n/ unique texture.

Looks like an interesting project

[gregsandor]

The forest is now in the main file.  The terrain textures match each of the leaf textures.  To use the clip file change the texture references and objects to your own, connect the populators to the Compute Terrain node and Planet, and link the Young Trees, Mature Trees, and Old Trees surface shaders into your terrain shading network.

[gregsandor]

Now more than 100,000 trees.  Is there a log that shows the number in a population?  I see the populator count, but it runs fast and I can't always get a good read.

[rcallicotte]

What a cool thread.  Thank you for letting us in on your research.

[bigben]

You can pipe the output of TGDCLI.exe to a text file to give you a running log. Just checked my work computer and it seems it also works with TGD.exe (did this by accident by editing tgdNo3DPreviewNoNetworkView.bat which I needed for starting a render via remote desktop)

%TERRAGEN_PATH%\tgd.exe > %TERRAGEN_PATH%\tgdlog.txt

Creates a log file in the same directory as your TG application.

[Oshyan]

Or if you just run TG from the CLI exe you'll get a window with the log output where you can reference the population counts.

- Oshyan

[bigben]

I prefer to pipe it to a log file in case it crashes    In the case of multiple populations this can be helpful in seeing possible memory issues if it does crash, and finding the specific culprit.

[gregsandor]

Thanks.  I set that up through the render dialogue, right?

Here's the latest incarnation of the terrain.  I modified the tree density system to also control grasses.