OpenCV Draw line using Angle

Here is the simple solution to find a point in an image when angle and starting point is given

Use the  trigonometric equations

 x2 = x1 + length * cos(θ)

y2 = y1 + length * sin(θ) 

Where θ should be in radians

θ = angle * 3.14 / 180.0

In OpenCV rewrite the equation like

int angle = 60, length = 200;

Point P1(150,150), P2;

P2.x =  (int)round(P1.x + length * cos(angle * CV_PI / 180.0));

P2.y =  (int)round(P1.y + length * sin(angle * CV_PI / 180.0));