How do I create a line or path to move from an object one ofVec3f/ofPoint position to another?

I have created an instance of ofMesh to create the shapes in the image attached.

I need to draw a circle that moves from the one vertex/vertices to the next?

How do I create a properly create a line that creates a path from one ofVec3f point to another.

e.g. ofVec3f point1(200, 200,0) to ofVec3f point2(400,400,0);