Annotated: electrosim.rendering.trails

draw_trails

• Reuses a cached alpha surface per window size; clears each frame.

• For each particle history segment:

  • Skip if jump exceeds half window (wrap discontinuity guard).

  • Compute age-based fade; draw an outer edge line with reduced alpha for a simple AA effect, then the core line.

• Blit the trails surface onto the main screen.