Scratch

Actually, trig functions are useful in a variety of things but have much fewer practical applications in scratch. But for the purposes of scratch lets just say its only good for curvy lines and finding directions 

Last edited by archmage (2010-07-17 12:34:36)

OMG THANK YOU! THANK YOU! THANK YOU!

(thank you x3)

Locomule wrote:

Not necessary Sunrise-Moon but thanks    Love your animated sig btw!!

Thanks  . Could you do a tangent tutorial soon?

Locomule wrote:

Sin and Cosine (or cos and sin in the script block) are simply curves. Yay! They are highly mystical and only for use by brilliant Scratchers, not!! The TINY amount of tinkering around below will get you acquainted with using them in minutes. Amaze your mother, win the envy of your peers...

make a new project, just use the cat sprite
make a new variable named oscillator
here is the script...
when green flag clicked
go to x:0 y:0
set oscillator to 0
repeat 360 times
change X by cos of oscillator
change oscillator by 1

Now run it and watch the cat move. Cool eh?
1) Did you notice the "360" repeat? There are 360 degrees in a circle. Hmmm?
2) Change that "360" repeat to a 180 and run it to see how the cat's motion changes. Try 90. Ahh.. so Cosine lets us move something in a circular motion! But you say, "Wait, that was just back and forth, not round?" Nope, it was round!    Its just that we were looking directly at the side of the circle instead of looking down at it!!

But before we 'flip' it, lets use our current script again.
Set everything back to the very first script EXCEPT change the cos function to sin and run it.

What was different about the motion? What was the same?
Change the "360" repeats to "720" and run it. Did you think it was gonna do a circle again, what did it do instead?

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So if you've had trouble before, forget the math of Cos and Sin and instead learn their mechanics in a Script. They are the OG tools for doing curves whether drawing or just moving sprites. Now lets rotate that lazy, sideways circle...

Reset your script again to the first version.
Add this block either just before or just after the "change X by cos of oscillator"...
change Y by sin of oscillator
run it

Hey, now our circle is standing up where we can see it! Wonder what you could do to make it an oval? What if you use 2 sines or 2 cosines? Try adjusting the "change oscillator by 1" to a different number. *note* if you want the cat to finish the circle where it started at, make sure that this number is always a factor/multiple of 3 such as 1, 1.5, 3, 6, 9, 15 etc, can be very important!

Peace and happy Scratching everyone!

cool!

Thanks So Much This Really Helps!!!!!!!!!!!!!!!

you have inspired me

pssst, here it is