Hi Friends,

One of my favorite Inkscape tools is the Spirograph extension.  Over the years, I've made probably hundreds of them.  I have one in particular that I want to work with, but it's not quite right.  I want to play around with the settings and change it somewhat.  Unfortunately, you can't select a spirogram and find the settings that were used to make it.  The dialog only shows you the last one you made with it.

I'm wondering if anyone knows the math well enough to look at a spirogram, and could give me settings that would be at least something close to it?

In case someone can do this, this is the one I want to get close to.  I'm almost positive it's going to use the Outside Gear Placement.  But I've just spent a good hour with trial and error on the numbers, and I can't get it.  I've gotten somewhat close, but not close enough.

It's the sort of inside-out flower effect that I'm looking for.  See where it looks like the daisy petals are pointing inward instead of outward.

Or if someone could give me some clues, I would still spend more time with trial and error.  But I need to narrow it down somehow.

🤞  Thanks!

EEerrrrch!!  Hold on!  Looking closely at this, it looks like it's been edited.  It might not have been made originally the way it appears now.

I wonder how I did that....???

Well, if there is someone who knows the math well enough, you can probably  tell whether it could have been made with spirogram extension.  If not, don't bother.  But if so, I still would like to know the settings, or at least close to them.

Thanks!

Aah, I think I figured it out.  Yes, that was not an original spirogram, but was edited to look that way.

Hi. 

Indeed that doesn't look as a epicycloid. First of all a ciklois is a somewhat smooth curve; there wouldn't be any spikes on the inside if there is a loop involved.

Then the ratios don't make it appear as it was drawn by rolling a circle on another one but as if it was drawn by rotating an ellipse along a circle-without actual rolling and then tracing some of those points.

A similar parametric curve could be plotted but it's way more advanced then just simply changing the ratio of the x and y radius of that base ellipse. 

These beiing said it would still be possible to deduct a similar curve that can be drawn with the extensuon. 

By eyeballing these two could match your curve partially.

edit: it also might be a hipocycloid:

Thanks for your comments, Lazur.

I finally figured out how I did it!

Just saw this, glad you got it figured out.  I wonder if down the line, they could chg the spiro to always show what was used to make it.  I've been in the same boat, want to recreate something and no idea what I used.

I filed a feature request for it recently.  I was going to file it some years ago, but at that time, someone told me (I don't remember who) they were personally already working on it.  So I didn't file it at that time.  But then, years later and I still don't see it, I decided to finally make the request.

Oh great, thanks!  

This is good for my vocabulary. But I somehow am not able to memorise those words, Lazur.

Beautiful flower, Brynn! When you are in a flow, it is very usual to not remember exactly what you did afterwards.
At least, that is what happens when I am painting. Hours go by and at the end of the day my hands are cold and I look at the clock wondering what happened.
Days later I look at my work and wonder... How on earth did I do that?
Being very creative does something with your mind that cannot always be repeated.

Perhaps there is some genious person who can write an extension to repeat your creative workflow.
Next time you feel you are about to make something spectacular, I can recommand using screen capturing software like CamStudio ;-)

Kirstie.  These days I try to type the numbers using the text tool, then it's right there when i need it!  I put several on one page and I'd never remember where I'd store a screen print, lol. 

Sorry, double post.

Oh Flamingolady,
After all that work that is a bummer! The screenprints... Normally in Windows, they are just copied to your clipboard, I think.
I use a program for that too, Greenshot. There you can tweak everything to your own liking.
That program always asks me what to do with a screenprint, so I cannot forget to save it.
And if you cannot remember where a printscreen was stored, it helps you find it back too.

Tell me, how did you get that cute picture that says  Skwark !  next to your name? And is it just for fun, or also referring to something else?

Those little images are "emojis".  Anyone can get one, but you have to ask a moderator to do it for you.  Just tell them which one you want, and if you want any hover text.

I can't see Flamingolady's one with "shwark".  It's just a box with letters in it.  (part of the reason I don't like emojis - apparently I don't have something on my computer that would let me see it)

Neat program Kirstie.  I think Brynn did the icon, i love  it!  No idea what skwark means though, lol. 

No, I didn't give you the icon!  I thought you must have done it yourself.  Since you're a moderator, you can.

We had a bit of a rogue moderator for awhile there.  They might have done it.

I cannot undo it anymore, but you can Dee.  Do you want me to tell you how?

Edit

Or, there is a way to find out who did it...maybe.  The Moderator Log should say, if it goes back that far.  I can't remember how long the log entries stay active.  But if you can remember about the date when it showed up, you can look in that log and find out who did it.

oh thx Brynn, but I love it, will keep it, doesn't really matter who did it.  I just noticed only a few days ago really! no idea how long it's been there. I do remember a convo on a thread so it may have been that person...

Or the bird flew in on his own.. I like to imagine ;-). I can see it on my Windows/ Firefox, but not on my Android telephone. Squark!
Thanx Brynn for the explanation!