Basic Building Question about Cylinders

I'm teaching myself how to build and so far so good. But I'm wondering... is it possible to cut a "doorway" into the side of an upright cylinder?

Here's the scenario: I made a (fairly primitive) underwater cave for my property using flat panels. But it occurs to me that the cave textures (photo-realistic cave images) I'm using would look better if I used a large cylinder with a domed roof. But this will only work if I can create a doorway in the side of the cylinder.

Any help would be much appreciated! (Even if it's to tell me I'm barking up the wrong cylinder .

Buzzer

With cylinders, just like with any other prim type, you have two options. You can use a texture with transparency to paint the doorway, or you can use multiple prims to sculpt it. I'd recommend the latter.

Here's what I'd suggest:

1. Rez 2 identical cylinders, and hollow them.
   
   
   
2. Cut away a section of one of them. For best results, cut the beginning and the end by the same amount. For example, if your beginning cut is .10, make your end cut .90. Symmetrical cuts will keep the prim easy to manipulate.
   
   
   
3. Cut the second cylinder so it exactly fills in the gap in the first one. If you used the numbers in the above example, then you cut away 20% of the first cylinder. So, cut away 80% of the second one, so that only 20% remains. Make the beginning cut at .40, and then ending cut at .60. Again, symmetry will keep the prim easy to manipulate.
   
   
   
4. Place the two cylinders at exactly the same coordinates, and rotate one of them 180 degrees on the Z axis. The two should now appear to be one.
   
   
   
5. Shrink the second cylinder (the one with 80% cut away, the smaller piece) by lifting the bottom. Leave the top where it is. Now it should look like one cylinder with a square cutout towards the bottom. Voila, you've got a doorway.
   
   
   
6. Put your dome on top, and you're done.

Cool, I'll give this a try.

Many thanks!