| The view, where section arrow to be displayed Notes: The curve_data spline is in the space defined by 0,0,0 mapping to the local xsec's reference point in world space, directions of X/Y/Z matching the X/Y/Z of world space, and the unit length being 'one inch in the top model of the view.' To map this to world space, first 1) scale the spline by 'inch to top model unit', then 2) scale the spline by 'top model unit to world unit', which is the scale of the transform from ProDrawingViewTransformGet(view_to_drawing = TRUE), then 3) translate the curve to place 0,0 at the reference point, To map a spline in world space for use here, do the inverse: translate it by the reference point to place that point at 0,0, then scale by world-to-model (inverse of the scale of the view's transformation matrix), and scale by top-model-unit-to-inch. |