How to draw a crescent

p5.js Coding Questions
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Thanks for the link Jeremy! I’d like to learn much more about astronomy actually. I took a year of it in school decades ago but I’ve forgotten most of it by now. Curiously, that’s the last time I took a formal programming class and the language we used was … Pascal! I also have very little memory of that, aside from spending a lot of time looking for missed semicolons on that big green bar paper printers used to use. :slight_smile:

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No problem Dan.

Reading some of the posts and answers on this Processing site there is not very much (how about nothing !!) that I can contribute as it is “way out” of my field of expertise. It looks as if there is not a great deal that I can contribute here.

Cheers,

Jeremy.

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Well I’m glad you contributed to this post!

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It works for me - just in case you were still waiting for an answer.
And it was animating just now - don´t know if you did anything to the code since you posted here

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When you say it animates, do you see the moon go through all of its phases, with the light continuously circling the sphere?

I don’t… I see the light kind of animating in on the left side, and then stopping. Which is odd, considering sin(frameCount) should continue to swing between -1 and 1… ?

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Now you asked specifically…
I saw what you described and thought it was animating slowly and I ran out of patience.
My bad.
To make up for it: as you linked your sketch in the editor I had a little poke and some Reference-reading and came up with one additional line

  let angle = frameCount/20.0; //was frameCount/10.0
  moonPG.reset();                    //was missing
  moonPG.directionalLight(255, 255, 255, cos(angle), 0, sin(angle));

Of course I didn´t save into your code - but I learned something about rendering

2 Likes
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Awesome! Changed it to include the reset. Thanks for finding that!

1 Like