Areas to decrease density?

[Lupaz]

Hi.
I have a mountain range and in one mountain there should be much less trees than others.
I tried multiple things such as using Areas>Distribution maps and painting a B&W map in photoshop, but I don't know how to control the UV mapping of this map which should be separate from the overall distribution map.

How can I control the density in certain areas of the surface?

[Paul Roberts]

Hi!

If you've updated to Forest Pack 8, then this would be an ideal use for Forest Effects. Using the new changes it's possible to use a spline to affect attributes of the scatter independently of the distribution areas. Attached is a sample file in which I've created an effect that allows you to reduce the density of items that fall inside a spline. There's also a falloff parameter for a smoother transition should you need it. The effect file is included separately if you want to import it into a different scatter.



For more about importing and using effects you can see the documentation here: https://docs.itoosoft.com/forestpack/forest-plugin/effects

I hope that helps,

Paul

[Lupaz]

I have Forest 7.3.1
I can get that effect by using Areas>falloff (global props)>Density>exclude but I run into what looks like a bug as described in this topic. I just sent the file to tech support.
https://forum.itoosoft.com/forest-pro-(*)/bug-with-superposed-elements-and-falloff-density/

[Paul Roberts]

I suspect that is a limitation with the way include and exclude areas are automatically extracted from surfaces when overlapping. Please try the following instead.

- In the Areas rollout, turn off the Surfaces layer. It'll still be used to calculate Z Position, but now it isn't used for area calculations.
- Add a large closed spline that encompasses the whole terrain, set to include. This will add back all the items over the whole terrain but will ignore the fact that the surface is split and/or overlapping for falloff calculations
- then add your exclude area to the top level.

Hopefully that helps,

Paul

[Lupaz]

I suspect that is a limitation with the way include and exclude areas are automatically extracted from surfaces when overlapping. Please try the following instead.

- In the Areas rollout, turn off the Surfaces layer. It'll still be used to calculate Z Position, but now it isn't used for area calculations.
- Add a large closed spline that encompasses the whole terrain, set to include. This will add back all the items over the whole terrain but will ignore the fact that the surface is split and/or overlapping for falloff calculations
- then add your exclude area to the top level.

Hopefully that helps,

Paul

Yes! It works.
Thanks!