Bug: Funky anti-aliasing

[athyfr]

With anti-aliasing, you can see the intersection points on lines, especially if you're zoomed out really far or using small stroke thickness:

With more complex documents, I imagine this could be a little irritating.

In addition, a fix would allow transparent pen colours, as mentioned here.

Potential implementation

One solution would be to use an intermediate rendering surface (per-stroke):

• The stroke would be drawn to its intermediate rendering surface, with only the alpha channel (for anti-aliasing) taken into account.
  • At this stage, the alpha mixing could use the max operator.
• The image from the intermediate rendering surface would be pasted onto the main viewport, with colour (and stroke transparency) applied.

Any overhead this may cause would be more than made up by keeping those intermediate rendering surfaces in memory for reuse until the user zooms in or out.

Thanks for the great whiteboard software!

[athyfr]

If this would be more appropriate as a feature request, let me know, and I'll do my best to rectify it.

[Prayag2]

I'm planning to create a feature like Excalidraw’s, which would resolve these problems and also support translucent colors. The idea is to generate a closed polygon using the current thickness, pressure, and points, so we’d paint a single polygon rather than drawing lines between points. The result would be very smooth lines with translucency support.