How do I create a square, Alpha Mask - always default to round?

Tips, Tutorials and Help
1

Hello,

I want to create a mask using the Lock + Radius option that drags out as a square (or the shape of the actual alpha) For example the Brick alpha is shown as a square but when I drag it out on my mesh it always ends up round. I want it to drag out as a square (the original shape of the alpha)

I have fallout set as a flat line but can’t find anywhere to remove the default round shape.

Any Ideas?

Thanks