Retina display

[rcarlier]

Hello !

I tested an update and the "gallery example".

Nice, a lot of work has been done since my last tests - well done!

But there's a small bug on Retina displays - (and I don't see if there's a setting to make it compatible).

2026/05/23 17:13:42 INFO adapter selected name="Apple M3" type=DiscreteGPU
2026-05-23 17:13:42.627 main[61888:10993826] +[IMKClient subclass]: chose IMKClient_Modern
2026-05-23 17:13:42.627 main[61888:10993826] +[IMKInputSession subclass]: chose IMKInputSession_Modern

FYI : I launched my "godocumentor" on ui (and gg) - with a search engine now!

• https://r-c.es/gogpu-ui/
• https://r-c.es/gogpu-gg/

Excellent work on internal documentation, by the way.

[kolkov]

Thanks for reporting @rcarlier! And great work on the godocumentor — those docs sites look really nice!

We investigated the Retina HiDPI pipeline in depth. The scaling chain (gogpu BackingScaleFactor → gpucontext adapter → ggcanvas → gg.Context) is architecturally correct, and previous Retina bugs (#123, gg#308) are fixed in current versions.

However, there are a few potential timing-related issues we'd like to narrow down. Could you please:

1. Check your gogpu/ui version — which version are you running? The latest is v0.1.29 with several HiDPI fixes.
2. Add logging — if possible, run with GOGPU_LOG=debug and share the output. We're looking for the ggcanvas.NewWithScale log line that shows scale= value (should be 2.0 on Retina).
3. Try forcing scale — does the issue persist with the latest deps?

This will help us determine if it's a scale detection timing issue (canvas created before macOS reports 2.0) or something else.

[rcarlier]

With pleasure!

require (
	github.com/gogpu/gg v0.48.4
	github.com/gogpu/gogpu v0.39.1
	github.com/gogpu/ui v0.1.29
)

For logs: https://github.com/rcarlier/tests-gogpuui/blob/main/20260523/logs.log