Hi Michael,

I am including a simple illustration of something I would like to be able to do.
Starting with the simple rectangle (say the base of a 2x4 stud in a framed wall) ... then extrude it to the height I want.
Then extrude it further by selecting the top face and extending it.
Then boolean union to make it one solid.

OK fine (thought sometimes boolean union does not work ... no idea why).

I would like to bypass a couple of steps sometimes ... just select the face and extrude ... 'stretch' into a longer (taller) solid.

Could this go on the wish list?

I am currently working on a small house and the owner requested some changes that required a considerable number of small 'stretches' ... a lot of fussing.

cheers,
eric

Hi eric - that kind of operation that you're referring to is often times called "direct manipulation" and it is on the wishlist.

There are various issues that can make it difficult to fully implement though.

For example, if your object is sloped rather than having 90 degree sides, more like this:



Then the extension that goes on a shape like that is no longer just a simple extrusion as in the case you showed above - instead the extension would be like this:



So that involves something more like an offset of the top face while having the side faces extend upwards until they hit the offset and have all those pieces be trimmed with each other. This is a much more difficult thing to handle than just an extrusion.

So when I do get a chance to work on this area, one thing that I'm not quite sure about is whether I should try to get a more fully general mechanism working that would attempt to handle things like I'm showing here, or if it would be ok to have one that only handled things like planes that have 90 degree side walls as in your example, which are potentially a lot easier to deal with.


There is a CAD program called SpaceClaim which is specifically focused on doing this kind of direct manipulation work - you might want to check that out if you want to have some tools in this areas working right now.

- Michael

Hi eric, also since you have Rhino you could try the "MoveFace" command in Rhino to see if it would help you with this kind of stuff right now - I don't think it handles the fully general case like with the sloped sides but it could probably work with 90 degree side wall geometry.

- Michael

In Sketchup, there is a plugin call "Smart Push Pull" that make that ;)
http://forums.sketchucation.com/viewtopic.php?t=23341
Don't know if you can see the images?

Yes, Michael and Pilou ..

Rhino will handle the rectangular section and Sketchup has some great tools, too.

I really like working within MoI whenever possible ... it is so friendly!

thanks,
eric

Autodesk Inventor Fusion does this as well. Check out the technology Preview (free for now) or if you have or are going to get AutoCAD 2012 or one of it's variants, it comes included.



This is an interesting preview, but it will only go to the logical limit when you click "OK":



It's definitely fun to play with if a little slow.

http://labs.autodesk.com/utilities/fusion/

Hi Eric

Probably you know already, If your solid is something like a wall you can always use the edit frame to stretch it. You have to click the corner first to send the point it scales from to the edge instead of the middle then pull it up.

Thanks, Jamie ...

No, I have rarely used the 'edit' box ... just for rotation, really.

In a minute or two of playing with it, I now realize that it is actually very powerful and that I must get familiar with it asap.

thanks again
eric

Very useful too for flat curves!