Hi! I''ve got a (hopefully) simple question: How can I convert a unified 2D Vector into a single degree-value? e.g. (just estimated) 0,1 -> 0 1,1 -> 45 1,0 -> 90 1,-1 -> 135 0,-1 -> 180 ...... Do you have any ideas? Thanks!!!!!!!!!!!!!!!!!

inverse tan

use arctan(), which converts x/y values into degrees. This should be standard in your compiler''s math library.

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The wind shear alone from a pink golfball can take the head off a 90-pound midget from 300 yards.

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In C, atan2(x,y) works better than atan(x/y) : no singularities and it covers all four quadrants. Results are in radians not degrees.

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This might also help:

if v is your vector and & the angle from initial position

sin& = y/|v|
and
cos& = x/|v|

since your vector is a unit

sin& = y
cos& = x

Usually, however, there are ways to avoid trig if you are using vectors.


"Free advice is seldom cheap."

Whats the application ?
If you say what it is for, maybe we can help you avoid trig altogether.