Get the angle and the distance of point from center point-CodePudding

I'm trying to make a color picker and need some help, I need to get an angle of a point from a center point, starting from the top moving to the left, highest value being 1 and the lowest 0, as well as distance between the two points;

I skipped math in high school so I'm at a loss, any help would be appreciated

CodePudding user response：

to find angle between center and the point in radians: Math.Atan2(point.y-center.y,point.x-center.x) normalize it: Math.Atan2(point.y-center.y,point.x-center.x)/Math.PI/2 make it start from top: Math.Atan2(point.y-center.y,point.x-center.x)/Math.PI/2 0.25 don't let it go below zero: (Math.Atan2(point.y-center.y,point.x-center.x)/Math.PI/2 0.25 1)%1 invert it so it goes counterclockwise: 1-(Math.Atan2(point.y-center.y,point.x-center.x)/Math.PI/2 0.25 1)%1

you can rewrite it as: 1-(Math.Atan2(point.y-center.y,point.x-center.x)/2/Math.PI 1.25)%1