Metaballs mode flickering more than with Obegränsad firmware

[Solmath]

Version

main

What happened?

On my device the metaballs mode is flickering really hard, while the blob plugin in the Obegränsad firmware is buttery smooth.

Could this be related to the PWM frequency or the increased number of gray levels?

There were also some changes to the blob plugin lately.

Note
I'm not using a level shifter yet. So this could also be related to my hardware setup.

Steps to Reproduce

No response

What did you expect to happen?

No response

Which ESP32 board are you using?

No response

Relevant Logs or Error Messages

Any other helpful information?

No response

[JanPetterMG]

	ph1p/ikea-led-obegraensad	VIPnytt/Frekvens
Pixel bit depth (gray levels)	6-bit (64)	8-bit (256)
Refresh rate (timer interval)	5 000 Hz (200 µs)	15 360 Hz (~65 µs)
Frame rate (equivalent)	~78 FPS	60 FPS
PWM bit depth (levels)	8-bit (256)	14-bit (16 384)

Disclaimer: I haven't tested ph1p/ikea-led-obegraensad since last spring. I took inspiration from the Metaballs PR, and made my own custom implementation of it, but I never tested the original.

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I think you're onto something, the PWM frequency (maybe also the number of gray levels) largely affects the performance, and I'll admit it flickers heavily at low brightness levels on my Obegränsad device. On my Frekvens device hover, it's perfectly fine, maybe not butter smooth, but quite smooth, even at the lowest brightness setting.

My recommendation is therefore to max out the brightness.

Both Obegränsad and Frekvens are using the same SCT2024 PWM-controller chips, so in theory there shouldn't be any difference between the two devices. The only major difference is the LED-diodes itself, so my guess is that the ones in Obegränsad are slower to respond, and therefore respond negatively to the higher PWM frequency.

You could try to experiment with a higher frame rate #define FRAME_RATE 78 // fps, just to get comparable results. In case the ESP32-S3 freezes, you might also have to increase the SPI frequency too, as I'm not sure how high the current SPI frequency will allow you to go. It's hard coded at about 8 MHz, but it works perfectly fine at 13 MHz too, which should give you plenty of headroom.