Pixel math-function graph using headless and framebuffer

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Pixel math-function graph using headless and framebuffer

Postby claudio4parallella » Tue Aug 29, 2017 8:50 pm

parallella.png
1024x768 FrameBuffer view
parallella.png (50.34 KiB) Viewed 8166 times


Hi all!

just a first test, as from attached image, I've generated a 1024x768 pixels as a graph of

y=w*sin(x), w=1/16, 2/16, 3/16,... 16/16

where every single y pixel position as per function y(x) where [x=0...1024] is individually calculated by each of the 16 cores of the Epiphany device in parallel.

As well as I'm using a headless Parallella configuration connected via ssh, I'm showing on my MacBook Pro monitor the image just using VNC Viewer and running on the Parallella Host side the framebuffer-vncserver, witn geometry of 1024x768 pixels.

The program is mapping pixels from graphs directly into the /dev/framebuffer of the Parallella, so the framebuffer-vncserver is showing the output.

I've been able to show some slow animations, too, using this approach.

The Epiphany is really fast, even if the display is very low and anyway this "model" could well work without a monitor and keyboard, headless mode, as per static pixel based graphic representations.

if anybody interested, let me know.

Ciao
claudio4parallella
 
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Re: Pixel math-function graph using headless and framebuffer

Postby jar » Thu Aug 31, 2017 12:05 am

I have also used X forwarding over SSH on headless parallella. You can output just a window rather than the entire desktop over VNC.

Do whatever works for you. It's not as responsive as a native display.
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jar
 
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Re: Pixel math-function graph using headless and framebuffer

Postby claudio4parallella » Thu Aug 31, 2017 8:55 am

Hi! thank you for your reply, just to get in touch within Parallella, could you explain how X forward from ssh does work?
I'll google in the meantime....
thanks
Claudio
claudio4parallella
 
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Re: Pixel math-function graph using headless and framebuffer

Postby claudio4parallella » Thu Aug 31, 2017 6:44 pm

x11 ssh forward ! yes it works!! thank you for suggestion
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