Tinkering With Spirographs in C++

[HYRULE]

The math around the spirographs I could see being useful for making little special effects or other sorts of fun mezmerizing things in a game. For example, in those vampire-survivor type games where you have lots of little weapons spiraling about hitting things automatically, defining their path in this way would be quite fun to watch.

[quicktastic]

I wear a Casio F-91W. I love how simple they are. I am also impressed at how accurate it is. It stays within a couple of seconds from my computer clock for months. It is far more accurate than any other electronic clock I have (that isn't synced to a time source of course).

[ForbinKid]

Pen being outside the wheel breaks physics, no man has seen (but this one has). I did this simulation very slowly back in 1971, but only had a flat bed plotter and Dec PDP10 basic to play with, so it was quite slow. I did do a few colours. I just through out the old faded 2 or 3 foot plots I had tucked away a couple months ago.

[landsgevaer]

Nice graph, but the pen motion looks off and the code is indeed slightly mistaken. Around 15:00 the curve briefly shows retrograde motion when the pen is close to the ring gear when it obviously shouldn't. The error is in the ratio. The circumferences ratio is used, but that is not the ratio of angular velocities. That should equal
ratio = Rfixed / Rmoving - 1
because the moving wheel is also making one full rotation inside the fixed wheel.
This is easy to see when for instance Rfixed = ½Rmoving, then the inner wheel makes one anticlockwise rotation, not two, when it circles around once clockwise. Or, when Rmoving = Rfixed, then the moving wheel should not rotate at all, i.e. ratio=0.
I invite you to try it.
Otherwise pretty nevertheless!

[greketrotny]

Amazing video! I also find spirographs quite mesmerizing. In this scenario, where we have two circles, and one rolls around the other without slipping, the `ratio` calculation has to be corrected by subtracting 1.0f from it.

[GodmanchesterGoblin]

Around 40 years ago I coded up the drawing of hypotrochoids like these in BBC Basic. It's kind of funny to see so much resource used these days to achieve a similar result. And I still have my Spirograph set from around 1968. The box is somewhat degraded, however.

[brawldude]

I check your videos time to time and find inspiration. Your projects are always so interesting olc!

[jeffreyphipps]

My Spirograph from the early 70s had a piece of cardboard and little push pins to hold the paper/outer gears (mine has two - yes, I still have it) and about ten smaller inner gears. I also have a Spirotot which was small and was a frame with self piercing paper holders and the frame contained the main/outer wheel and instead of gears used inner wheels (yes, still have it too). I also have my Mechanograph which allowed a user to pin paper and inner wheels and shapes to cardboard and use the wheels and shapes to draw around the inner shapes. There was one shape that was a human shape.

[KDMAAB]

Just at the end with the last circle and the colour changing, I was reminded of the Captain Blood "Hyperspace, activated".

[gedaliakoehler]

End result was very pretty. Nice video. I do question why vacations weren’t as fun at night though 😂

[unknown_error]

That would honestly make a killer screen saver.

[michaeloneill]

Nice video! This reminds me of the flight patterns used by enemies in Galaga

[jumbledfox]

love your videos, keep it up!! hope you had a lovely holiday

[daveking-sandbox]

If you could decrease the size of the inner circle on every iteration, I could imagine you could draw spirals.

[natsuhiboshi]

Awesome video, a beautifully broken down solution!
Thanks for sharing this with us!

[KerboOnYT]

Neat! I remember being fascinated with spirographs as a kid

[BrekMartin]

That’s fine. I can’t help but think your entire time on YouTube was a lead up to this. It’s a shame it’s out of reach for the Lynx, and I’ll have to revisit on the next platform!😅

[tomkirbygreen]

The worlds smallest house appears to be a 1 x 2 Lego brick :-)

[WinterSina]

"I like this a lot". Mee too brother, ty

[minirop]

I was indeed annoyed by you stoping the rainbow too soon.