Applied-Scientific-Research
Boundary Features Rotates Incorrectly
When a boundary feature is centered on a point other than (0,0), it follows a circular path around its center instead of rotating in place.
This is a known issue, and there is a workaround. When creating a boundary feature that "moves according to formula", there are two positional inputs: "center" pair and "x position", "y position" formula fields. This obviously confusing. Consider the formula inputs (for position and rotation) to define the movement of a virtual marker. And consider the "center" positional input to be the position of the new boundary relative to that marker.
Eventually, we will need to support these markers as first-class objects, creating them individually, drawing them, allowing them to attach to other markers, while allowing all kinds of features attach to them.
As an example, if you wanted to dynamically pitch an airfoil about its quarter-chord point, you would generate an airfoil, set the "Leading edge position" to (-0.25, 0.0), and set the "angular position" to sin(t).