Slow card editing on software display backend on windows

Note: yes software rendering is meant to be “slow”, but it is anyway a recommended way of fixing various glitches on windows version as indicated on FAQ. So this issue should be considered even if it’s expected. Also Qt’s QWebEngine is hardware accelerated regardless of

example glitch) BUG: Card view sometimes doesn't update

Anki’s editor is extremely slow on the software display engine when HTML size is big enough, or there is an image on the card.

Note) QT webengine display is hardware accelerated despite anki using software display backend, as qt’s rendering is decoupled from the application’s rendering since Qt 6.5 (Note: current Anki uses Qt 6.9). A simple test navigator.gpu ? “WebGPU supported” : navigator.userAgent; suggests that GPU acceleration is on in the AnkiWebPage.

I haven’t looked into this issue in detail, but Anki works smoothly on the reviewer side, so I suspect the webengine itself’s performance is pretty okay. I suspect the slow rendering is due to how Anki renders the editor form in the editor.py.

Possibly, we need a better profiled image of the entire application.

Dunno if this issue fits better here or the github issues page. Triage needed.

Can you test with Shift editor control to TypeScript by abdnh · Pull Request #4029 · ankitects/anki · GitHub? Does that make any difference?

2 Likes

With PR, experiencing about the same amount of lag as the current version.

Maybe I should check if webpage itself is indeed using the gpu acceleration.

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.