Creating windows, doors, vents etc

[Schmalspur]

I have a question, I'm building a locomotive and have got an extruded object that is near enough the correct shape, I want to put windows and doors etc in with a cab visable inside, how can I make the model hollow so when I subtract a shape to produce the window I have the inside of the loco visable? I tried making a box that just fitted inside the loco and subtracting it but left me with many stange polygons all around the model! How can I do this?

Thanks for any and all help,

Regards, Jack

[dkightley]

Hi Jack

Have a read here:
http://forums.uktrainsim.com/viewtopic. ... a&start=11

One way of achieving what you want to do is described there. In fact, the whole of the two aircraft tutorials would be worth a read...you'll pick up some ideas.

Another way of achieving what you want would be to make the body "double sided". Then, when you cut a hole, you'll see the inside of the other side. And indeed, you don't have to even cut any holes....use transparency on the inside and outside textures.

[decapod]

Using boolean subtraction works best if the object is manifold - i.e. has no holes and encloses a space.

I would make it double sided, select all the inner or outer faces and extrude by a small amount before subtracting the windows.

Subtraction usually requires a bit of welding to fix up the odd extra points that get created.

[Schmalspur]

I tried using the subtraction, but it seems to leave the inside of the object subtracted in the window, so it's like pigeon hole, great for putting the mail in but not so much for looking out of! Is there a setting I'm missing to stop this? Both sides of the object have faces, and are extruded a little.

Thanks, Jack

[decapod]

Here's how I would do it.

Start with a cab object (In this case from my cab builder plugin with no thickness) - Right click on the object "Show Only" is a useful function here
Select the interior faces and extrude by about 0.01m (1cm)
click for large image...


I then create a long cube and chamfer the edges several times to get a rounded edge. Position it through the front face.
I then duplicate it and position it through the opposite side.
I combined the cubes at this point.

The subtract won't work through the front and back at the same time so I keep a copy of the cubs for subtraction from the other side of the cab.



Here's the subtracted result:


Run the weld to range plugin set to 0.001m to clean up some of the extra points that subtraction creates, optimize and consolidate.

[Schmalspur]

I was doing it with a solid box, after seeing your box with an open bottom/top I tried it again but this time removed the floor, and it seemed to work, it made a few weird faces inside but once they were deleted it seemed fine.

Thanks for the help!

Regards, Jack