Hi Burr,

> I love this command! Still the need to get it in my
> head, but so very cool!

Maybe it will make a bit more sense if I show the internal intermediate stage.

So with the 2 input curves like this:



The booleans will internally create extrusions for those, the closed curve becomes a volume and the open curve becomes a surface, like this:



Then "intersection" means to take the parts that are common to both objects. For a volume and a surface it will take the parts of the surface that are also contained within the volume, which gives this result:




But it's kind of nice to be able to generate this result just directly from the curves and let the booleans internally deal with extrusions of pieces into surfaces or volumes instead of having to do those as additional manual steps.

- Michael

Hi Michael

"Where at least one of them is closed, then it is actually possible to generate a surface directly from those curves by using Construct > Boolean > Isect."

obviously this is much simpler,

...of course

Thanks !!!!!

Vincent

Hi Michael,
Thanks again! I remember this from a thread that had me cracking up for a few days! More just that I dont "remember" this method and usually do the boolean diff-deletes faces-try to constuct the surface thing when it is so simple as this.

Just need to remember this method to "bring to mind" when doing things!

Actually, you make a good point. If I put some thought towards how the tools are doing what they are doing, it will be an advantage for me to figure the right method for my modeling.

Thanks again.

Side note: 1 week and 4 days. Give Mrs. G and baby some love from my family.

Hi Burr,

> More just that I dont "remember" this method and usually
> do the boolean diff-deletes faces-try to constuct the surface
> thing when it is so simple as this.

One thing though is that the "reconstruct the surface" part can be bothersome - on something that has a smooth outline like this you can pretty easily get some kinds of unwanted compression or subtle stretching in corner areas when trying to surface it with a sweep or something like that.

When you have an extrusion that is cut to the smooth outline shape, it tends to be more simple and better geometry, because the underlying surface is such a simple straight extrusion in that case.

Another way you can do it though is to use Trim instead of any booleans at all, that works like this:

You take the side curve and extrude it into a surface like this:



Then select the surface, and run Edit > Trim, and select the Top view curve as the cutting object. The Trim command will then cut the surface up by the projection of that curve and show the available pieces like this:



Select the piece that you want to discard like this:



And then when you exit the Trim command you will have this result:



So that's another way you can do it where you have some more individual control over what pieces are going to get thrown away since you specifically select the pieces with Trim unlike the booleans which are oriented more around automatically discarding pieces based on where they are in relation to the volumes.


> Side note: 1 week and 4 days. Give Mrs. G and baby
> some love from my family.

Thanks Burr, it's hard to believe it's already been 6 months!

- Michael