[1.1.25][mac] White screen on startup with eGPU on internal display

[briosche]

Hi all,

I've got a bit of a strange set-up that I think is confusing Factorio: I'm using an external eGPU (AMD Radeon RX 560 in the Sonnet breakaway box) to accelerate my internal display on a Macbook Pro 2018. Factorio works fine (although very slowly) if I don't tell it to prefer the eGPU in its Finder settings, but once I turn that option on, it only shows a white screen on start-up, although sound still works fine. The log shows a ton of OpenGL invalid_framebuffer_operation errors. This issue persists with any of the options changes in the Common Graphics Problems, using Steam or the standalone game, changing the native display resolution option, changing the display resolution, or using a different version of the game. I can't find any similar issue on the forums or online, although there are a couple posts online showing somewhat similar problems on other games. I've attached my log in verbose mode and config.ini below. Thanks!

[PVollenwyder]

I have had the same problem with Factorio 1.1.26. But with slightly different hardware. I'm using a Mac Mini 2018 and a AMD RX580 eGPU. I also had the eGPU connected similar to how a laptop would be connected with the display (a 4K TV) connected to the Mac Minis HDMI port.
under MacOS 10.15 Catalina this worked with good performance with all of the graphics setting turned up.
After updating to MacOS 11.3 Big Sur Factorio would no longer use the eGPU. Running on the Intel Integrated graphics worked but due to the lower performance I would have to reduce the graphics settings (low resolution sprites, turning off some animation options,....).

When I connect the display to the eGPU HDMI output it is used for graphics rendering and the performance is back to what it was under Catalina.

Also I was able to run Kerbal Space Program with the eGPU providing acceleration while connecting to the Mac Mini HDMI port, so this is not a general error with MacOS