Brush radius/connectivity control

[gdevenyi]

Right now, the brush radius for segmenting is a bit odd. I'm not sure what units it's in, I would expect a "1" to be a single voxel but it isn't, I need to go below 1.

Similarly, it would be nice to control the "connectivity" of the brush to allow for (including)/(not including) diagonals.

[rdvincent]

@gdevenyi The radius is approximately in millimetres, so the default size is huge when dealing with a mouse brain.

Not sure exactly how the connectivity control would look. Can you elaborate?

[gdevenyi]

Re: units, I wonder whether voxel is more appropriate.

As for connectivity, I envision a control similar to mincmorph:

Kernel Options
-2D04: Use a 2D 4-connectivity kernel.
-2D08: Use a 2D 8-connectivity kernel.
-3D06: Use a 3D 6-connectivity kernel. (default)
-3D26: Use a 3D 26-connectivity kernel.
-kernel: <kernel.kern> read in a custom kernel file