## Angle of Repose Function

Started by WAS, December 16, 2019, 02:35:36 PM

#### WAS

I was curious about creating a procedural angle of repose simulator. Which would sample the terrain and generate a map of what slip, and what would not. I'm not sure if I actually have achieved this goal (I don't think so looking at smaller geometry with steep edges), and wanted some advanced minds have a look at it.

The issue I'm encountering is how to derive "distance" from the terrain, as obviously real distance of the noise map is finite, how can we take displacement and get area that could procedurally feed the formula?

I realize I certainly could just use the slope keys, but I was working on ideas for the pre-work for a project, and I wanted this to be more accurate and not look uniform along slope angles, as the angle of repose works a bit differently (which is why snow on mountains for example isn't exact to sloping, as buildup along a lower angle can support higher angles, etc)

Update: Doing some thinking, I believe using displacement to scalar is best used for the "height" of the terrain (Y). Distance I am still confused about but believe could be derived from X and Z of the terrain somehow. Now sure.

#### Hetzen

This sounds like an erosion calculation. What ever you do outside of a simulation is going to be an effect when working with an already defined landscape.

Knowing a point's height is one thing, know how close it is to an edge is something only a particle sim can work out.

#### WAS

I may be wrong, but the Angle of Repose is based on already defined geometry, unless you're specifically dealing with piling.

I was hoping to figure out a "basic" angle of repose for different slopes or angles.

Which could then be used as a mask for filling, alterations, etc

https://sciencing.com/how-8071705-calculate-abutment-wingwall-length.html

#### Valri

Curious, this seems like you are trying to create similar functions to the "heightfield mask by feature" node in Houdini, I don't suppose you know of Houdini's terrain toolset do you WAS?
Put that in your pipeline and smoke it!

#### WAS

Quote from: Valri on January 10, 2020, 01:30:19 AMCurious, this seems like you are trying to create similar functions to the "heightfield mask by feature" node in Houdini, I don't suppose you know of Houdini's terrain toolset do you WAS?

Maybe somewhat like the curvature keys, yeah I suppose that would be a good comparison. And I'm not too familiar, no. I have used it only once my self while at a friends, and quickly crashed it (lol) and I just called it quits there not to take up any time hanging out.

I am interested in a number of features in Houdini, though, as a matter of fact. I've eyed it for a while.

Also, welcome to the forums!