Any recommendations for a small Raspberry Pi screen to display oF projects?

Hi,

Has anybody had any luck with one of the smaller screens and a Raspberry Pi to display openFrameworks projects?

I’m in the market for a small-ish screen (ca. 10cm), but don’t really know what to get.
I’ve been eyeing the Pimoroni Hyperpixel ones, but they seem to have some downsides, like for instance not being able to show anything, when the OS hasn’t booted to desktop.
I also have the official 7" touchscreen, but that’s too big and I’m already using it with another Pi.

Any recommendations or other tipps?

Thanks.

I only used two, one HDMI, 800 x 480 which I like, (XPT2046 Touch Controller, 5inch hdmi display)
and another one smaller, connected to GPIOs which I think it is difficult to use. both of them are stylus touchscreen but I never bother calibrating.
they don’t have a very good angle of view if it matters, I’ve been only using for software output, interface, debugging, etc.

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Thanks for the reply. I’m primarily looking for a display. Touch functionality isn’t really required. The mediocre viewing angles might pose an issue for me since, it’s meant as display, something like a small digital photo frame.

They’re very small but the Pimoroni HyperPixels are gorgeous.

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I’ve been using some small screens some time ago and figured out that any (cheap) screen is OK as long as it connects via HDMI. Some even come with a compact U-shaped HDMI connector. All the screens that connect on GPIOs don’t support hardware acceleration, making them worthless for oF usage.

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That’s good to know! Unfortunately, I’ve already purchased a Pimoroni HyperPixel.
If I don’t get it work with oF, I guess I can still use it for another project and buy a cheaper HDMI screen.

I’ll keep this thread updated with my findings.

Despite initial doubts, I’ve got openFrameworks to run with a headless Raspberry Pi Zero 2 W and non-touch, rectangular Pimoroni HyperPixel display.

Here are a couple of things to note about the HypePixel:

  • it occupies all GPIO pins, which makes it hard to connect anything else to the Pi, but you can still use some I2C devices by making the display use the alternate I2C interface, which will free up two pins (3V3 and GND are also still available)
  • the display is currently only supported under Raspberry Pi OS Buster (Pimoroni is working on a driver for Bullseye though)
  • the installation of the screen is super easy - it’s done with a single shell command - but it needs to be installed after downloading openFrameworks and installing all of its dependencies
  • it’s a gorgeous display, but as @Daan pointed out above, hardware acceleration might not be supported this way, since the screen isn’t connected via HDMI

And here are a couple of remarks concerning openFrameworks and the Raspberry Pi:

  • I installed the nightly build of_v20211128_linuxarmv6l_nightly.tar.gz and it seems to work great so far
  • I couldn’t get a compiled project to run from the X desktop environment, since the GLFW library can’t be initialized somehow, but this isn’t what I wanted to do in the first place either
    glfw_error
  • running the project without X and its overhead works fine, but as stated at the bottom of the oF guide, xorg needs to be installed first from the package manager and it fortunately doesn’t break the display output
  • the memory split mentioned in the oF guide wasn’t really necessary, since the GPU is by default set to 64MB, and the option doesn’t even seem to exist in the raspi-config of the Zero 2 W anyway

So far, I really like the setup! The display is nicely lit and sharp. It features a resolution of 480 x 800px.
My test project - a self-avoiding walk simulation inspired by this video by Daniel Shiffman - runs great!
It was run with the startx ./bin/selfAvoidngWalk -- -s off command from a terminal, connected via SSH to the Raspberry Pi.

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Here’s another test run, inspired by one of @danb’s great YouTube tutorials, which I guess was inspired by one of @zach’s legendary lectures. :slight_smile:

The colors really pop! I’m super happy with the display so far.

And you can really get a small profile of the overall contraption. With the Raspberry Pi Zero 2 W the thickness, including the screen, is about 1cm (0.39").

that is super cool ! such a great form factor - how was the speed without acceleration ? were you able to make a comparison? (also glad you like the video - am taking a break for a little bit due to a new gig in a new country but have more planned)

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With the two examples above, I got 60 FPS easily, but keep in mind that they’re not too demanding. I still need to try some heavier examples of mine.
Honestly, I currently don’t see any difference between my desktop computer and the Raspberry Pi, in terms of running the compiled binaries.
The Pi Zero 2 W seems to be powerful, especially considering its size and price. I believe it’s equipped with a quad core CPU. They could have bumbed the memory to 1GB though. We’re stuck with 512MB for now.

Are you kidding? I love your videos, even the cooking ones. Great stuff and so creative! I’m glad that you haven’t given up on your YouTube channel yet. :slight_smile:

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I’ve tested the same setup with BullEyes last week or so, it’s working fine, although i used the round display.

BullsEye isn’t working quite right though and compiling from a shell through ssh rather than on a screen will hang, and not output an error - bit frustrating as the compilation will already take a little long :frowning: -.
Also need to remove a flag for compilation.

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I’d tested it last week too, but I couldn’t get it to run. And after some research, I simply gave up on it. :wink:

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@diff-arch LOL - i didnt think anyone saw the cooking! - I have more in the edit (making ramen noodle, soy eggs etc) waiting to be finished.
I’ve been using pi 3 & 4 but not tried the zero 2 yet - really good to hear you got it all working ok

Looking forward to those, if you ever decide to release them.