Scrolling is very laggy

markusschwenk / midieditor

Provides an interface to edit, record, and play Midi data

GNU General Public License v3.0

467 stars 69 forks source link

Open PROPHESSOR opened 5 years ago

PROPHESSOR commented 5 years ago

This is most pronounced when scrolling using the touchpad.

markusschwenk commented 5 years ago

Did commit 1b8c6a1 fix this?

PROPHESSOR commented 5 years ago

markusschwenk committed 8 days ago

PROPHESSOR opened this issue 2 days ago

No.

easyaspi314 commented 4 years ago

The main issue occurs from a repaint hell. When I was working on a macOS version a few years ago, this popped up.

Every time the screen scrolls even a pixel, the entire editor invalidates and repaints the whole screen.

A fix would be to either cache regions or find a different approach (such as QGraphicsView or something).

However, these are not very trivial to implement and required large rewrites.