A Hotkey to temporarily suppress the Ruler constraint on the fly while drawing

I'd love to be able to quickly suppress having my cursor/brush lines constrained to the ruled perspective projection lines.

I find myself drawing and trying to adjust organic shapes but  cutting in with the ruled lines,  and it would be handy to switch on the fly.

If this already exists, I haven't been able to figure it out!

Hi Flimflam,

If Perspective tool is active on canvas, the brush will always follow the perpective lines.
You need to turn the Perspective off by closing the Rulers panel ( hit the x button on the panel or use shortcut Shift + R ).

Another option is to assign a direct shortcut for the Perspective tool via Rebelle's menu: Edit > Keyboard shortcuts > Edit > Perspective Tool.
Hitting this shortcut on and off will enable / disable the Perspective tool on canvas while the Rulers panel will remain open.