Axonometric grid spacing lower range is too big

[Yann Papouin]

Axonometric grid spacing lower range is too big, it doesn't allow the use of an axonometric grid with 16x16, 24x24, 32x32 icon design.

My use case:

I tried to create a 32x32 icon.
I'm using the canvas of the same name.
I'm using an axonometric grid with spacing-Y set to 1.0mm by default
After creating the global shape of my icon, I want to add details
So I set spacing-Y to 0.25mm (current grid div 4)

After investigating:
It's not working because the limit of spacing-Y is hardcoded to 1.0px (~0.27mm)

I changed this hardcoded limit to 0.05px, that is really correct at a maximum zoom.

[Diederik van Lierop (mail-diedenrezi)]

Patch looks ok, I've just committed it; But I wonder, do we need a hard coded lower limit at all? Wouldn't enforcing only >= 0 be better? Someting else I noticed is that it is still possible to enter values lower than that in the document properties dialog, without those values being clamped, and that way too many axonometric grid lines are drawn when zooming out (for rectangular grids the number of grid lines is limited when zoomed out)

[Diederik van Lierop (mail-diedenrezi)]

BTW, Yann I assigned this to you so that you'll get the credits for this in the bug hunt tally.

[Yann Papouin (yann-papouin)]

Values entered in GUI are clamped when grid is computed, there is no return to the GUI to say to the user that he is out of range.
I chose 0.05 because I first set 0 for min limit and saw that It was useless and after some tests, I concluded that 0.05 was the minimum usable value at a maximum zoom.

But you're right about the too many axes drawn when zooming out.