In Vanilla (Pure Data 0.48.1) when a scalar gets any of it's values [set] (even the ones that don't impact how it's drawn) it seems to get redrawn resulting it to move on top of any overlapping scalars. This behaviour seems to be platform independent (tested on Windows 10 and OS X Yosemite). This is a problem since GUIs and such often rely on overlapping elements and working around it makes a patch a lot more complex.

Here is a simple test patch, it sets the (unused) float "test" on a scalar then it overlaps the other scalar:

scalarset.pd

My questions are, is there a way to prevent this from happening without clearing and redrawing the whole thing, and is this worth reporting as a bug or a suggestion to fix?

Thanks for the reply, I was aware with the $0 thing being purely Pd-l2ork but habits die hard, the reason I did not bother fixing for vanilla is that the overlapping scalars have a layering problem at least in Windows, what happens is that when one of the scalars gets [set] it places it on top of the other ones and I'm not sure how to fix that without making the patch a lot more complicated.

I almost forget to thank @Jona for the pointer list patch and special thanks to @corvett for the repeated key fix:

I would like to share my little keyboard abstraction.

Visualizes MIDI notes in and sends out MIDI out from computer keyboard (polyphonic) and mouse. Tested and fully functional on Windows 10 with Purr Data 2.5.1 but sadly the overlapping scalars where very glitchy in vanilla so I did not bother fixing it.

scalar-keyboard.7z