Any Thoughts on a Framebuffer?

[aphistic]

The project I'm planning to use Hubris for is going to include a display (either OLED monochrome or TFT color, I haven't decided yet) and I was wondering if there were any plans to include something like a "framebuffer" task that would interact with display drivers and provide a consistent API for rendering? Forgive me if I'm using terminology wrong, I haven't had a chance to dig into Hubris aside some of the docs yet.

I don't know what your use of Hubris is right now, but I imagined you might have some status displays you would want to include on your systems at some point. I thought maybe you'd considered that and had some thoughts on the matter? If not, I'll probably just blaze my own trails and break things as I go! :D

[labbott]

A framebuffer isn't on the official plan. I'd be very interested to see what you come up with!

[pokeylope]

I've been goofing around with getting Hubris running on my Flipper Zero, which uses an ST7565 controller over SPI. I have it to the point where I can draw to the screen (using embedded-graphics), but I haven't yet figured out the interface to let other tasks interact with it.

[pokeylope]

I now have graphics working over IPC. The display-api driver provides a DrawTarget implementation that sends the commands to the display task, which then forwards the calls to its own DrawTarget for the actual hardware, so it should work for any device that has embedded-graphics support (although I only have the one to test it with). It's still got some rough edges (for example, error handling should be improved, and it doesn't attempt any sort of mutual exclusion), but it works fine.

[mchodzikiewicz]

This is cool!
I am a bit afraid that IPC round trip between each primitive is quite hefty overhead for any sort of higher level GUI, but that's a good start!
I could try to port your example to STM32 LTDC and see how it goes

[mchodzikiewicz]

I mentioned this discussion in an embedded-graphics issue about adding flush() method/trait for committing a drawn frame to the display - it would be useful to implement sending set of drawables through IPC

[ghost]

@cbiffle @aphistic

Consider checking out Slint.

They have demos for 2 microcontrollers; STM32H7, RP2040

Enjoy.

CC: @tronical