[2020-07-02] Quick Stroke Mode for slow machines

The "Quick Stroke Mode" is added to version 2020-07-02. This mode pauses the flow and temporarily renders the current stroke with less fidelity for increased interactivity.

As a reference, the FPS I get when stroking on Surface Go (HD Graphics 615 GPU) goes from 40+ to 60+. On Surface Pro 4 i5 (HD Graphics 520 GPU), from 30+ to 90+.

Toggle this mode manually here (plan to automatically offer users to switch to that Mode when slow performance is detected):



Less fidelity means you will see lower-resolution 'staircase' artifact at the new stroke's edge, but once you are done with the stroke, the whole piece would be rendered in high resolution.

Quick video to show you the idea:



So, now even if you have a slow Intel integrated GPU, you can use Expresii more smoothly. Of course, a faster GPU is still recommended for the best experience.