Scratch

jujubee834 · 2010-02-15 14:10:52

I am trying to make a model of the phases of the moon

can someone help me by telling me how i would make the moon rotate around the earth in a circle?

thanks SO much!

juststickman · 2010-02-15 14:29:09

Quick question before I explain: Do you want the complicated math way or the simple way?

jujubee834 · 2010-02-15 17:37:10

haha obviously the simple way

Paddle2See · 2010-02-16 16:46:00

Well, the easiest way is to edit the costume of the moon sprite and set the Costume Center (little plus sign button) outside of the moon, some distance from it in fact. Then, just put the Turn blocks inside a Forever loop and you will get the result you are looking for.

juststickman · 2010-02-17 11:05:16

I was busy with homework and Paddle2See answered it for me, that's the simple way.

markyparky56 · 2010-02-17 11:30:49

The hard way uses trig, and im still trying to find the project i saw it used in. I think it was mayhem's but i think he deleted it. sad

juststickman · 2010-02-17 11:50:33

markyparky56 wrote:
The hard way uses trig, and im still trying to find the project i saw it used in. I think it was mayhem's but i think he deleted it.

Basically you do this for the moon sprite:

<when green flag clicked>
<forever>
<go to x sad (( X position of the earth <+> (( sin of <direction> <*> how far away )) )) )y sad (( Y position of earth <+> (( cos of <direction> <*> how far away )) ))

And turn.
(I think)

Last edited by juststickman (2010-02-17 11:50:55)

markyparky56 · 2010-02-17 14:34:26

juststickman wrote:
markyparky56 wrote:
The hard way uses trig, and im still trying to find the project i saw it used in. I think it was mayhem's but i think he deleted it.
Basically you do this for the moon sprite:

<when green flag clicked>
<forever>
<go to x (( X position of the earth <+> (( sin of <direction> <*> how far away )) )) )y (( Y position of earth <+> (( cos of <direction> <*> how far away )) ))

And turn.
(I think)

Thanks! it works!

Scratch

archived forums

#1 2010-02-15 14:10:52

HELP with rotation

#2 2010-02-15 14:29:09

Re: HELP with rotation

#3 2010-02-15 17:37:10

Re: HELP with rotation

#4 2010-02-16 16:46:00

Re: HELP with rotation

#5 2010-02-17 11:05:16

Re: HELP with rotation

#6 2010-02-17 11:30:49

Re: HELP with rotation

#7 2010-02-17 11:50:33

Re: HELP with rotation

markyparky56 wrote:

#8 2010-02-17 14:34:26

Re: HELP with rotation

juststickman wrote:

markyparky56 wrote:

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