[SOLVED] How to get the angel of a right triangle rectangle giving as an input (a & b) cathetus?

Unity Engine
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2998610--223495--upload_2017-3-18_14-21-31.png
2998610--223495--upload_2017-3-18_14-21-31.png800×410 139 KB

float a
float b
angle = atan2(a,b) ?

SOLUTION by makeshiftwings & lordofduct

float a = 2f;       //  cathetus maggiore
float b = 2f;      //  smaller cathetus
float angle;      // result in  degree

angle = Mathf.Atan( b / a);       // result from 0 to 1.570796...
angle = angle * Mathf.Rad2Deg;   // convert it to degree

print(angle.ToString());      // 45°
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2

You have it backwards… SOHCAHTOA says Tangent = Opposite / Adjacent.
angle = atan2(b,a)

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3

SOH…
Sine: sin(θ) = Opposite / Hypotenuse
…CAH…
Cosine: cos(θ) = Adjacent / Hypotenuse
…TOA
Tangent: tan(θ) = Opposite / Adjacent

So:

tan(theta) = (b/a)
theta = atan(b/a)

atan2(b,a) would also technically work… because a right triangle guarantees that you’d have angles less than 90. But is technically overkill since it also calculate direction, and would result in odd values if you say passed in negative side lengths.

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