Rendering refactor

[0awful]

Multifaceted re-render:

• mark rendered lines as render once the line meets two criteria

  • The last line segment has been received
  • The last segment has been drawn

• Periodically remove rendered lines from the drawing object

The render function only redraws what is in the drawing object, so we shouldn't see a loss of performance once we switch to this method.

• Periodically convert the drawing to a different more performant data type?
  • It's an option, but we might not need it.

[0awful]

fixed