Box Challenge

[illusory]

I've come back to this problem a number of times since beginning with LW about a year ago. I've tried many things, various booleans, and lately the tunnel plug-in here:
http://plaza17.mbn.or.jp/~PICTRIX/index2.html
which seems to offer the best chance of a solution, but I haven't been able to do it yet.
I wonder if anyone can figure out how to accomplish this:

1.given two long subdivided boxes (as in the pic)
2.one is copied from the other, placed on another layer, and rotated
3.'hollow' them out so they meet cleanly INSIDE as well as out, like, say, two corridors would meet in a hallway.

so, the result would be one construction, with a wall-like structure.

the next pic shows one of these boxes 'tunnelled' out with the plugin.
If anyone wants to play with this, i'd be happy to email you the file.

Anyone interested?

thanks for any ideas,
NJ

[illusory]

next pic, box tunnelled

[evilemil]

make a cube, that you want to use as a cut out, fitting to the first subdivided cube you created.
copy both objects to new layers, rotate them both, so that you have the subdivided and the not subdivided, but smaller cube, fitting with each other.. now make a union boolean on the outer, subdivided and then booelean substract the inner ones.
this should give you the result, you want.

[richpr]

I've come across the issue many times as well...

In this example I would probably extrude/smooth-shift the side walls (after subdivision) from the main section... and then boolean holes through both corridors. If the subdivision is not accurate enough, you could add a cut or two with Knife...

The boolean add/union doesn't work nicely with the cross structure when their Y are very similar or equal... In some cases I change the Y of one of the objects...

In some other cases I kill all the polygons and rebuilt the needed structure with new polygons from the remaining points... This is before subdividing anything ;)

[CoryC]

Are you looking for something like the picture below. It was made with a few booleans and a little clean-up of some bad polys. Do you need to have so many subdivision and not as many on the inside? I think there may be a faster way doing in in halves and mirroring it.

[richpr]

Another way would be to make the X with a single n-polygon, extrude that to give it thickness and then drill the corridors...

The extruded n-gon could also be 'Jullienned' to create the subdivision if needed...

[CoryC]

I tried out doing half and mirroring it and it works pretty quick. I made a subdivided rectangle same X and Z size as before but only 1 division on the Y. Copied and Unioned the two to get the X shape. Then selected all the 'wall' polys and smooth shifted in increments for the subdivided wall. The 2 sharp corners needed adjusting, then mirrored.

[riki]

How come the mesh res is so high?

Can't you work with something like this? Subdivide it later if needed??

[richpr]

Attached is the little test I did... a corridor with 48 points...

1. Create flat box 1 (4-point poly) (corridor 1)
2. Copy it to another layer and rotate... (corridor 2)
3. Drill the copy via slice onto the first box. Creates intersection points of the two flat squares. Cut the copy back to layer 1. You have the X with intersection points.
4. Kill polygons and redraw a single polygon out of remaining points...
5. Extrude this new polygon...
6. Create thick boxes to boolean into the new shape. Create box no. 1 in second layer, switch layers, boolean subtract the new box from the extruded X.
7. Rotate and move the box in the second layer for the second corridor. Boolean subtract again...
8. Flip polygons to determine what is inside and outside...
9. Merge points ;)
10. If you don't like the n-gons, split them...

[richpr]

Here's the object

[riki]

Here's my approach

[hrgiger]

There is a plug-in which I believe is called thickener which would probably work nice for this.

[illusory]

Wow, thanks for all the incredibly useful replies! Can't wait to try them out tonight when i get to LW'ing...

Quick reply to the question, "why such hi-res?" That's just temporary in order to use the Tunnel plug-in, after which I used Unify Polys to get rid of the excess. But from some of the replies, looks like I may not need that plugin anyway.

Strangely, after posting last night, I finally did actually manage to figure out a way to solve the problem, but my solution is more labor-intensive than it ought to be. A lot of rebuilding polys around the inside intersections. Seems there are some much simpler ways shown in this thread -- i'm real interested in checking those out.

many thanks!!!
NJ

[SLAYER]

Ikedas connect is one of my favoeites. I use it for connecting odd ball things together, but it works great for this as well.
With something like this, you would select the poly (or polys) on each end of box and hit connect. It would connect the two ends by deleting them and thus hollowing out your box!.

[illusory]

Riki and Richpr, I tried both your methods and they worked great. Thanks so much for the mini-tuts. Thanks Cory also.
I'ts really useful to see how something can be accomplished in entirely different ways.

Plus, I didn't know that the 'skin' command would work the way you used it, Riki, makes a lot more things possible! This method produced the right kind of geometry for my purposes, and i didn't even have to rebuild those thin polys around the inside of the intersections. Very fast method.

Again, many thanks, everyone, it's amazing what can be learned here on this forum. think i have the Ikedas plug-in, gotta check that one out too.

NJ

[riki]

As hrgiger mentioned before 'Thickener' also helps to speed things up. I mention it in my tuts. Worth checking.

re

http://www.suture.net/tutorials/modeling/page12.shtml

[illusory]

Riki, thanks for the link to your page -- many useful tuts there!
I was wishing for something like CPLANE to align model parts on complex angles, looks like it will be a major help.

thanks for everything,
NJ