Where do I choose gravel strength?

[dv2000]

Hi,
What is the proper way to choose gravel strength inside General properties>gravel roughness or Input Properties>gravel shake amplitude.

What is the difference and why there are two of these settings for one thing? Thanks

[Patrik Martin]

Let's have the concept of a road with gravel then the settings would correspond somewhat to:

• Gravel roughness (configure->general properties)
  How often uneven stones are placed going down the road. Or in other words how often are they different from one to the other?
• Gravel shake amplitude (input property)
  How big of a span is it between the largest and smallest stone.