No image preview on printing after upload

[LukasJasin]

What is your question?

Having problem with image preview on my MKS TFT35.
If I use option to start printing after upload there is no preview of file the image is black. But uploaded file is fine it does contain image and it shows in printing from SD card menu after upload.

When the file is already uploaded to SD and I start print from interface then the image is showing correctly.
The gcode contains image and device does display it. The problem is with automatic printing after upload. When this feature is enabled no image.

I have latest Cura 5.2.1 and latest MKS Wifi plugin 1.4.1

Firmware is also latest for MKS TFT35 1.0.8

Maybe I'm missing something some setting? Tried searching but no one seems to have this issue.

Any thoughts?

[Elkin-Vasily]

Try to use latest version from devel branch of this repo

[Jeredian]

@LukasJasin, is this question still relevant to you?
What printer model do you use?

[hobibilgisi]

For anyone still hitting this on modern Cura (5.13), the root cause of the missing preview turns out to be that cura.Snapshot.snapshot() returns None reliably on 5.13 due to an OpenGL/QQuickView timing issue (log: Failed to crop the snapshot even after 10 attempts!).

The symptom in this issue (black preview on auto-print) may or may not be the exact same bug, but the underlying preview-injection failure on 5.13 is now tracked and fixed in #420 / #421 (fallback to Snapshot.isometricSnapshot() which is independent of viewport render state).

Full write-up: https://github.com/hobibilgisi/MKS_Wifi_Plugin_Thumbnail_Error_Fix