Tool activity is not applied "in order"

[CandyAngel]

Description of the problem

This may be an issue exclusive to low-powered machines, but I came across it while drawing on my Motion Computing LE1700 at 25% zoom. If I did a large eraser action (with the top of the stylus) and then switched back to draw mode (by bringing the tip of the stylus close to or touching the screen), the tool would switch back to draw and the "erase strokes" would continue being applied but with the draw tool instead.

Basic system details

MyPaint version: 1.2.1-7 Operating system: Arch Linux Desktop environment: None (i3 window manager)

Steps to reproduce

1. Start MyPaint
2. Do a quick drawing
3. Do a large eraser command
4. Switch back to draw tool
5. Observe the eraser strokes are now drawn instead

[jplloyd]

This behaviour remains the same in the master build and is not directly related to the machine being low-powered (although it is easier to demonstrate on a slower machine).

I don't think it's a question of order - but simply a question of the brush stroke always being drawn using the currently active brush, regardless of which brush was active when the input coordinates (and pressure values, etc.) of the stroke were recorded.

Whether or not this behaviour is desirable, or if it could be easily changed to record the brush that was active when the stroke data was originally recorded, is something I don't know.