Hi mharr, typically to make a shape like that longer later on if you don't have the original curves around you would probably duplicate the existing edge curves on the object using copy and paste, and then just delete the shape and use those duplicated curves for editing and reconstructing. If you just stretch out the bottom like you are asking about it will change the angle which the bottom piece connects to the top piece, and that can then make that connection to be a sharp connection rather than a tangent connection.
In order to maintain a tangent connection with the same radius ball on top, you can't just drag out the bottom the location for where the bottom segment touches the top ball has to be redone as well, you would do something like that by starting a new line at the bottom and using tangent snap to snap it on to the upper part's curve and that will give you an exact tangent meeting point and then you can trim the upper curve with that new line.
If you don't care about maintaining tangency then it is possible to just yank down the bottom surface in your particular situation there, you can do that by turning on surface control points. In order to turn on surface control points you'll need to use Edit > Separate on your object first to break it into individual surfaces, then you can select the bottom surface, use Edit > Show pts to turn on its control points, select the bottom ring of control points and pull them down, and then rejoin the edited surface with the upper one. But as I mention above if you do it that way you will not have a tangent connection there anymore.
Surface control point editing is possible to do in MoI but it's not a major focus for how to generally do things because you can only edit control points of an "underlying surface". In your particular case here the underlying surface is aligned with the bottom edge of the thing you want to manipulate so it would work ok here but if the edge had been created by a cutting operation it will probably be a "trim edge" which is not necessarily aligned with the surface control points. See here for some more info about how "underlying surfaces" and trimming edges work:
http://moi3d.com/wiki/FAQ#Q:_Why_does_show_points_work_for_some_objects_but_not_others.3F
The general method that MoI is more focused on is constructing things from curves and in generating your surfaces from those curves. If you need to edit a surface there are various ways that you can extract curves from it if you do not have the original curves handy anymore, often times just using Copy and Paste to duplicate existing edges is the easiest.
- Michael |
