I'm trying to figure out how to create a custom circle shape in Visio using the ShapeSheet to dynamically calculate the diameter of the circle relative to a control point.
The control point is essentially the vertex of an isosceles triangle and the diameter of the circle is calculated as the base of the isosceles triangle using a user variable for the angle of the vertex of that isosceles triangle.
The effect is the further you drag the control point away from the circle, the larger the circle gets, but the constant 'angle' of the vertex affects the rate that the circle would grow.
I know the trig for this diameter=2*control_distance*tan(vertex_angle/2) but since a circle isn't a fundamental shape in Visio (rather an ellipse is), I don't know how to accomplish calculating a circle with a shape sheet.