I recently followed along with the Project Titan Ivy Tool tutorial [www.sidefx.com] and absolutely loved it.


https://imgur.com/a/Rd56dwO [imgur.com]

It worked very well inside unreal engine, except there is still one thing bugging me.
If I throw it on the model of a house for example. There will also be Ivy growing on the inside of the house.


https://imgur.com/a/Rd8Jquo [imgur.com]

Now i could maybe manually set every object this would be used on to exclude centrain prims/points from spawning ivy. But I was wondering if there would be a more procedural way of doing this.

Is there a way to calculate a light value and only have points based on how much light geometry would be receiving?