point from angle and length

[denisT]

http://www.cgafaq.info/wiki/2D_Point_Rotation

and it'll be good for you to check http://forums.cgsociety.org/showthread.php?f=98&t=295257
on this forum...

[Thorn444]

Hi thanks DenisT for your help but i already read all threads in this forum and of course that one which you linked me was first but which i have checked i really didn't find answear to my question or i am just not so good in math . But that your first link to wiki page looks like what i am looking for. So just for sure my function will be counted from :

x' = x cos - y sin
y' = y cos - x cos
so once again when i have a = [0,0] b = [1,0] c = [?,?] angle between a and c is 45 degree and distance is 1 how will be look that final function with these numbers :)? Thanks

[Neuro69]

Not entirely sure what you are doing, but:

len=10 --length to new point
rot=eulerangles 0 0 45 --angle to rotate
new_vector=[len,0,0] --a vector of the required length, along the positive x-axis
new_point=new_vector*(rot as quat) --new point

[Thorn444]

Hi

Yea that's. This is what i am looking for . It's looks so easy now when i can see final result but i spent two days find way how i can find that point. Thanks mate.

[Neuro69]

Possibly more elegant:

len=10
the_angle=45
new_point=[cos the_angle, sin the_angle, 0]*len

no rotation, just sin/cos.

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