Bug 289333 – [GTK] Touchpad pinch to zoom does not work smoothly

• Status: RESOLVED
• Resolution: FIXED
• Component: WebKitGTK

[Kdwk]

When using a touchpad to pinch-zoom, the web page instantly changes scale without the animation in between.

WebKitGTK 2.47.90
GStreamer 1.24.12
GTK 4.17.7
Libadwaita 1.7.0
Distributor: GNOME

[zyxhere💭]

Sometimes its smooth for me othertimes its instant or choppy

[Sebastian Krzyszkowiak]

It's more that it often catches multi-second lags than being choppy in general. If you wait for some time before releasing the fingers and keep moving them, it eventually starts acting smoothly for a moment before catching another lag.

This started happening in 2.48 - can't reproduce on 2.46 - and it applies to touchscreen zoom gesture as well, not just touchpad. Can be seen with both GTK3 and GTK4.

[zyxhere💭]

I should mention the pinch to zoom with a touchpad is buttery smooth in evolution but choppy in epiphany and Minibrowser[GTK4]

[Sebastian Krzyszkowiak]

That's because Evolution forces hardware acceleration to be off. You can run Epiphany or MiniBrowser with WEBKIT_DISABLE_DMABUF_RENDERER=1 and it will be smooth as well - that is, as long as your device can keep up :)

It doesn't appear hardware/driver specific - I can reproduce it on both Intel and Vivante GPUs.

[Sebastian Krzyszkowiak]

Pull request: https://github.com/WebKit/WebKit/pull/61215

[EWS]

Committed 309900@main (1f39a7f2d79b): <https://commits.webkit.org/309900@main>

Reviewed commits have been landed. Closing PR #61215 and removing active labels.