Issue #11675: Fade x Jitter dynamics now sync correctly at every step
By updating the fade_point for every point on the line, we make sure that the fade dynamic applies step by step, as previously it would change values only at the start/end of the line.
The video attached recreates the steps, for normal line, Shift+click, and Ctrl+Shift+click:
Closes: #11675 (closed)
Edited by Cheesequake