I don't understand Regions

Hello: I read the help on Regions, but I'm still confused as to why they might be used and what are the advantages of using them.

Do anyone have an example of why they use Regions?

thanks,

Proctor

You have to use the Region command on a closed loop before you can extrude it to make a 3D solid. As far as I know, if you aren't doing 3D, the Region command has no purpose. If there is some other purpose for it in 2D, I'd be interested to learn it myself.

Ernst: thanks for your reply. I've never worked with solids, but that is good to know.

As far as I know, if you aren't doing 3D, the Region command has no purpose. If there is some other purpose for it in 2D, I'd be interested to learn it myself.

Region can be subtracted from each other - so you can cut islands in the area at the same time. Easy method to calculate an area minus islands.

Also check out boundary command for a more powerful method of creating regions.

Notice in the attached that there is an ambiguous intersection with the long vertical line on the left. No need to trim, break at point or some other gymnastics. Simply create a region using the Boundary command and one click in the area also finds islands. Subtract the island regions from the "room" and you have the floor area.

wow, I can certainly see how that would be useful. thanks for explaining.

Proctor

Ok Proctor, you got me curious. One appilcation for Region in 2D that I can see would be similar to converting something into simple block. If you draw a rectangle using the rectangle command, you can grab a corner and stretch it. But if you region that same rectangle, you can't stretch it anymore. It will only move if you grab a snap and drag it. Same with a circle. Try it. Draw a circle. Now click on it. You have snaps at the center and quadrants. If you grab one of those quadrant snaps you can change the size of the circle by dragging it. If you region that circle, then click on it, the only snap you get is the center. You can no longer stretch it, only move it. So in a sense you've converted that shape into a block without having to go through the steps of making a block. Now let's say you draw 2 concentric circles, then region both of them. You can move each one individually. But if you put up your Solids Editing tool bar and us the Subtract command to subract the inner circle from the outer circle, it still looks the same on the screen but the circles are now locked together, like a donut. If you click on it, both circles highlight and you get the same center grip but both circles will move together if you drag that grip and drag it.

Up until today I'd only ever used Region for 3D but now that I've thought about it, I can see a use in 2D: Giving a geometry set properties similar to a block without actually creating a block, and a block drawing file.

Thanks for sending me off on that little exploration. :-)

Yes, JD, I see how that would be handy too. Thanks much.

Ernst: thanks for the great insight. i tried everything you did - except when i got to the part about putting up my solid editing tool. how do i do this?

I'm enjoying learning about this stuff too. do you think ...if i had an inner circle and the outter one, it would be easy to identify somehow if the outter circle did in fact contain the inner circle?

Thanks again,

Proctor

Proctor, Right click on any of the docked toobars and that will pull up the toolbar menu. There you will find the Solid Editing tool bar. On that are three buttons each showing two overlaping circles. Thsoe are Union, Subtract, and Intersect. When using subtract, you frist select the geometry you want to subtrct from, then the geometry you want subtracted. I'm not sure I understand your 2nd question. Can you clarify?

E.