Unicorn Hat - First Days Tinkers



Im new to the RPi, Python and Unicorn hat, some I was pretty pleased when I got it up and running quickly. I tinkered around a bit and tried a few of the samples. I saw the rainbow didn’t show all the colours, so I thought I would knock up my code to see if I could make something that would and here’s what I came up with…

import unicornhat as u
import time
import math as math



def shift(l,n):
    return l[n:]+l[:n]

freq = 0.1
while True:
    for i in range(64):
        r = shift(r,1)
        b = shift(b,1)
        g = shift(g,1)
        r[7] = int(math.sin(freq*i+0)*127+128);
        g[7] = int(math.sin(freq*i+2)*127+128);
        b[7] = int(math.sin(freq*i+4)*127+128);

        for x in range(8):
            for y in range(8):
                u.set_pixel(x, y, r[x], g[x], b[x])

setting freq to 0.05 and i to range 128, and putting a time.sleep(0.1) after the u.show() will give a much more subtle fade between the colours.




More tinkering on Day 2 :)

Now have a nice RSS feed scroller working…

next step to see if I can get a twitter feed scroller.


Superb stuff. I’ve just got my Pi and Unicorn HAT and some sort of Twitter/HAT integration is going to be my first little project!


How did you get on with the Twitter Feed scroller? Love to see code examples of this and the rss feed one - i learn by othercode (noob)!!!


Thanks for the video. I’m still struggling a bit with understanding the code, but it’s pushing me to read up and learn about Python arrays and matrices. :-)

Ah, as I write this I think I can see what it is doing. I couldn’t understand why you only had one dimensional arrays for the r,g,b variables. I assumed this was to be used in relation to the x,y location. But now I think I see that they are there to produce a stepped colour change and I assume the use of sin gives a curved colour gradient rather than a linear one, and the difference in the formula allows for a cycling through the colour space?

I did a bit of maths at Uni (but obviously not enough!)



Hi Andrew,

Did you post any code to drive the scrolling display anywhere ?

I just got a Pi 2 setup with the Unicorn Hat and would love to tinker with scrolling text.

Cheers - Paul