For my “shape-only” watchface I wanted to do a real moon sickle outline. Since one can’t do a partial border around a circle, I had to do it myself. I succeded after hours of math brain wrecking. Only 50% done, though, will update in the next few days.
circle formula galore. My brain hurts, I’m telling ya …
Fantastic calculations. Something similar was done, but with images and without borders and using 2 circles and 2 rectangles but that was trying to more accurately simulate moon phases. It could be done with shaped but the non centred anchor of rectangles makes that bit more difficult.
Perhaps you could make a nice fusion of the 2 for a shape based moon phase. I tried but just by trial and error and a serial condition on size and shape. It failed to run on watches. This seems much simpler so far.
Yeah, I even thought about taking latitude/longitude of watch position in account - that would make it necessary to treat the simple shapes in my example as a “faux clock hand”. So the moonshade doesn’t always slide in from the right. Should be possible with existing expressions/tags. But I admit this is all a bit much for me wee brain, but I’ll be relentless 
In my example the formula sadly needs a three-way-conditional:
1: moon shadow is to the left of the moon = distance between the circles is negative
2: moon shadow is to the right = distance is positive
3: new moon = distance = 0
WIll do this first, then I’ll very happily try an amalgam of your example and my calculations.
Because:
“Why do dogs lick their testicles?” - “Because they can.”
Funny, I just messaged you something that might help with that.
I was a bit stuck on a transition face and discovered that, if doing just maths, no text, you can make the conditionals as complex as you want:
Ah! That’s a real thing here! Will need to take this into account - I think I read about this yesterday while browsing! Cool! Absolutely stunning idea, by the way, this number juggling!!
Thinkg is: To get REAL moon phases, I think one has to gradually increase the radius/diameter of the shadow circle until half moon, when it’s almost infinite, so you get a perfect half circle, then the same again in a negative progression.
What I’ve been doing so far is just sliding one circle on top of another. Which means the moon itself always has a convex form. Which is fine for my simple face (and my other faces where the moon is relatively “symbolic”, but doesn’t cut it in reality.
I will wrap my brain around this. But now I’ll drink, because it’s my 56th birthday. Cheers!!
Happy Birthday. Have a goodun! Just under 5 years ahead of me.
We’re 2 years apart, many happy returns 
This we have to do just in case whe resort to the built in elements only, where we have no elipse shape and are using circle section as replacement.
Happy Birthday!
Happy Birthday to you . Here is a working example of Peters Smooth / Voodoo Moon . I love it .
Oh and one of his Fonts . Thank You Peter .
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Nice. I do like that font.
I also did a bit of an extract and example in that thread but a way further down.
I loved this screen, the colors, letters, moon…everything!!!
Thank you @christianfernandes38 . Mostly made with Community Gifts and a Picture Licence Free from NASA . 
Great thoughts and examples!! Still affixated to my shape-only thing, I must admit, gotta get this out of my system.
I tried a bit of exp() tomfoolery for the waxing phase:
Gotta make the exponential curve more extreme - slower at the beginning, to preserve the “sickle” shape longer. Could well be I’m getting there, though. Might get a ChatGPT account sooner or later for the guesswork - would probably save some fruitless thinking time …
That is really good.
Also, I know all about the fixations. I try to do as much with text as possible, though that is partially laziness and declutter as you can have one element for active and dim screens.
Currently dual fixating on mask template making and delving into uses for complex contitionals and their limitations.
I think I may be on to something. I guess at least it works for the first two phases
https://science.nasa.gov/moon/moon-phases/
(Plus: the demo looks like a very ealry 3D computer game sequence, hahahaha. “Starglider 2” anyone?)
For phases 3 and 4 moon and shadow will have to switch places, won’t they?
I do admire these text magic examples - it’s a very impressive method, and I really can’t see much lazyness there. I would love to give this field a go soon - completely different field of un-knowledge on my part
Yes. I think so. You need either a left and right mode or a hollow circle that can be huge around or small in.
See my failed one made by trail and error with serial conditions for each phase, rather than a calculation. Totally falls over on a watch but works in creator to give a visual:
Looks cool and clean! What’s the problem with it?
Ah! That’s also a very nice one! Getting envious here