Hi MrNobody - it sounds like you're looking for what's called a "history based parametric CAD" program, which isn't really what MoI is right now.

There are quite a few parametric CAD programs out there like SolidWorks, Solid Edge, Pro/E, Alibre, etc... so you would want to use one of those kinds of programs to get these particular features.

Since there are already a lot of mature programs like that out there, when I started MoI it was not really a focus area to just try and replicate the same feature set of these already capable programs, instead I really worked on making MoI have a different kind of focus, more about trying to make modeling things really quick and fluid and easy to create basic shapes.


> 1. Extrude and revolve appear to be done as parametric operations (I can go in and change
> the base curve and the extruded surface will update to reflect the new dimensions), but fillet
> is not. Would it be possible for fillet/chamfer to be parametric as well in some future version?

There is a history mechanism in MoI currently, but it's limited. If you have all of the input objects present in the model and also an object that was generated from them, if you then edit the input objects, the output object will be recalculated.

But the main limitation of this is that all of the data involved must be currently present in the model at the time of the edit. This is not the case with a fillet because when you do a fillet the old unfilleted version of the model is removed and replaced by the filleted result. So that means that the old unfilleted version is not around anymore.

In the future I do want to improve the history mechanism to make it deeper and keep previous object versions around so that limits like this could be removed. That is a fairly involved piece of work that will have to deal with storing potentially very large amounts of data and looking it up quickly, so it's going to take a lot of work to implement that.


> 2. I can modify the length of an edge, but it changes all of the other dimensions of the object.
> Would it be possible to constrain some other edges to a fixed value? It would make simple
> CAD work a whole lot easier...

There isn't currently any constraint mechanism in MoI, that's another thing that those same other programs like SolidWorks, SolidEdge, etc... do handle though, so again if that's a feature that's important to you, you should be targeting one of those kinds of programs for your work and not MoI.

Really the main way in MoI to edit something is to just draw a new version of it how you want. For simple things this is not really a big deal since the whole process of drawing things is quick in MoI.

I do want to add more kinds of editing functions in the future but for now if you need to edit complex parts one of those other MCAD programs is going to be a better fit for that.

- Michael