This enables an extra layer of control in the sculpt brushes.
For now it is enabled only in Scrape, but it should work in all brushes (like normal radius). In the future it may also be enabled in other brushes.
You can tweak in this property in the scrape brush to achieve a much better behavior when working on curve surfaces and control how much volume you want to trim. In most cases, it also fixes the bug where the brush keeps trimming in the same area without disabling accumulate.
It should be possible to fix some other artifacts in other brushes by tweaking this default property.
Reviewed By: jbakker
Differential Revision: https://developer.blender.org/D5993
df45257ec5