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Sin, Cos, Tan

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n_ick2000#

Sin, Cos, Tan

I learned in my geometry class that sine, cosine, and tangent were triangle angle ratios. Exactly how do sin, cos, and tan effect superscopes and movements. I heard something about triangle angle ratios being in degress and superscopes and movements being in rads, but I don't know what that means. Can somebody please explain this to me?
UnConeD#
Trigonometry 🙂

The easiest way to explain is this:

Given a circle with radius 1 (the so called 'unit-circle'). We take a random point on this circle. We can describe this point uniquely by the angle of the radius through this point and the X-axis, for example 90°, 140°, ...

Mathematically however, radians are used instead of degrees. Without going into much theory, you should just remember that 360° = 2*PI.
So suppose we have a point lying at N radians on our unit circle. Then the X coordinate will be given by cos(N), and the Y coordinate by sin(N). That's the definition of cosine and sine.
So if you want to draw a circle, take every value A from 0 to 2*PI, and plot the points (cos(A), sin(A)). Easy.
The relationship of sine and cosing with right-angled triangles is pretty easy to see. Draw a circle using the origin (0,0) as center. Take a point on this circle, connect the point with the center, project the point on the X axis. Voilà: a right-angled triangle appears 🙂

Sin and cos have other uses as well. Because they are coordinates of points lying on a circle, they are periodic. A point traveling along a circle will eventually arrive at its starting point. This means that their values are repetive after a while (2*PI to be exact).

So you can use sine and cosine as a source for a pulsing/wavy scope or movement.

The tangent tan is defined as sin divided by cos. It ranges from negative infinity to positive infinity in -PI/2 to PI/2, and repeates itself every PI.

Usually you won't need the actual mathematical uses of these functions, but you'll rather be using their characteristics (e.g. repetiveness).
UnConeD#
Nick 🙂

While I'm pretty sure I have not been cloned, I'd appreciate it if you'd stick to my actual nickname 🙂
buffer_brazil#
I Want to Learn About Sin, Cos

I Want to Make Cool Equations on My AVS Editor but i Don´t Know very few About Sin, Cos, Tan ... Where can I Get Documentation about it??

If You Have Documentation about it, please send me!
Angry Weasel#
There's also arcsine(asin), arccosine(acos) and arctangent(atan).

I find that d=atan(d) has a nice effect as demonstrated in Justin's age-old plugin that's no longer available, Gold Shower in Pseudo 3D.
n_ick2000#
Justin didn't make it. Lone did. It was in an older version of winamp. Justin removed a blur and added biliner filtering because bilinear filtering wasn't there when lone made it.
Kagnar#
This is off the subject, but

I noticed something. If you highlight (click and drag) over a smiley face emoticon, it turns to a sad face! Well, sort of.