Angle of a line?

[Razor89]

If I have two coordinates for a line, the begining and the end,
how do I find what angle the line is pointing relative to the begining of the
line?

I need this for a upcoming project where I need to move the camera in
a 2D world and it has to follow a line thus I need to know the angle which
the camera needs to move at.

Thanks!

 

[Joe Mamma]

If I have two coordinates for a line, the begining and the end,
how do I find what angle the line is pointing relative to the begining of the
line?

I need this for a upcoming project where I need to move the camera in
a 2D world and it has to follow a line thus I need to know the angle which
the camera needs to move at.

Thanks!

tan θ = (Y2-Y1) / (X2-X1)
θ = arctan((Y2-Y1) / (X2-X1))

 

[Razor89]

I think I might be able to work with that weird looking
formula but do you have any code by any chance?

 

[Joe Mamma]

I think I might be able to work with that weird looking
formula but do you have any code by any chance?

Oh it is sad that simple trigonometry is weird


look up Math.Atan

 

[Razor89]

Dim lineAngle as Single = tan(arc((Y2-Y1) / (X2-X1)))

or

Dim lineAngle as Single = Math.Atan((Y2-Y1) / (X2-X1))

Is that correct?

 

[Joe Mamma]

Dim lineAngle as Single = tan(arc((Y2-Y1) / (X2-X1)))

Is that correct?

nope. . .

Dim lineAngle as Double = Math.Atan((Y2-Y1) / (X2-X1))

 

[Razor89]

Ok, thanks, Im not good with math and I havent made my way to algebra
yet so please bare with me

 

[Joe Mamma]

NOTE THAT ATAN IS A DOUBLE!!!!

 

[Joe Mamma]

or
Dim lineAngle as Double = Math.Atan2(Y2-Y1,X2-X1)

 

[Razor89]

Ok, another thing is, does this return in degrees or radians?
I assume radians.

 

[Joe Mamma]

look up Math.ATan - complete example