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cctoide

Building modeling questions and techniques

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I'm planning on modeling some buildings and I've been looking at the released ArmA 1 models to see how BI did it. I've gotten decent results with my own models so far but I'm left with a few questions...

I've noticed most BI buildings, except very small ones, are usually divided into "cube units" - the building facade is divided into a series of repeating elements. There's a door element, a window element, a pillar element, and so on. I assume this is so all these repeating parts can be textured using the same UV space, but I'm curious to know what sort of workflow they used for this.

I tried replicating their method by modeling my elements out of a plane and welding them together to form a facade, but this makes it harder to add trim and other parts before stitching the model together, which leads to my other question...

Is it bad for a building model to be made of several separate elements, instead of one or two contiguous meshes? Some of the BI buildings have windowsills, roofs, etc. as separate elements, but dum_istan3, for instance, is made up of a single mesh for the main building and a second one for the staircase. As long as the separate elements intersect eachother slightly wherever they meet, will it look OK ingame, or does it mess with shading/performance?

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Hi!

I just graduated as a carpenter so this thread cought my eye :)

I am not very good at english, so I have tried to understand your text as good as I can.

I would begin with creating the entire house first. Then I would google for reference pictures, and use them to create the textures for the house. First, create a image wich is 1024x1024 or 2048x1024 or any other resolution you find suitable. Now you should create the UV and shadow map. If you have photoshop this stage will be easy. Download the Nvidia normal map tool from..... somewhere =) Place the roof texture wall texture and the textures you get to fit in that 1024x1024 or 2048x1024 image. You may very well use multiple .paa files for a house. You do not need to fit every detail and texture into one .paa file.

I wont write more on how to texture. If you need help just ask. Since I do not know if you know this part already.

Then about the construction of the house. It is easier to build it in separate blocks first. Then merge the points into one single object. IF YOU WANT. This is not neccesary BUT if you do not do this there might be small narrow holes where the blocks meet.

I REALLY hope this has answered your questions, and I apologize for my english. And if you need help I am more than happy to help you.

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i am in my final year at architecture. I can honestly say i got plenty of experience with making designs for various projects (all not fitting in the BIS environment though being..out of place for it).

Regarding 3d models for houses:

Build it in 3d as your would build it in real life i found the easiest. Obvioulsy, you could model it as a whole (although i found that harder, especially for rendering and visualisation).

I don't have experience with A1/2 building models, but can't work too differently from other game engines:

1. faces/objects can very well sink into each other. The shadow LOD needs to be properly done though.

2. it is easier to use the UV space for one model, although there are tricks you can do, depending on which software you are using..

3. Using the same UV space for multiple elements is also possible, and recommended where possible.

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Thanks for your input. My main doubt was about the workflow BIS used so that each element of a building could reuse a single section of UV space.

The whole thing smelled of box modeling, so I went ahead and tried doing that. I think I have a decent workflow for getting similar results. I started out by very roughly box modeling the house, getting the basic shape down. Here I made sure that the faces on both sides of the box have identical dimensions, so one side has 3 3,45m segments and is 10,35m long, the other has 4 3,45m segments and is 13,8m long, so all of those faces are interchangeable with eachother.

Next I detached the faces and cloned them (the original face stays where it is, since the position data is needed later), then made my elements out of those - a window, a double window, and a door. With these selected the Align tool can be used to align them to the original detached faces (works nicely since the edited faces retain their original pivot point, the corner vertices align perfectly), slotting them into place. They can be cloned and aligned as needed to make the desired facade, and then reattached to eachother and their corner vertices welded to make a finished building out of "units" that can share the same UV space since they're topologically identical.

I haven't quite got to the UV mapping yet since I can't get TexTools to work, but I imagine after this it would just be a question of stacking each element properly and then creating the texture.

Update 13 June: Alright, I've got pretty good results with the above method like I said, and I think I've got the texturing side of things figured out. It is indeed possible to copy UVs between topologically identical objects in Max, by copying the Unwrap UVW modifier from the mapped object onto an identical but unmapped object. Also, so far, attaching all the elements together and welding the corner vertices together doesn't seem to mess with the unwrap (joy!) so it should all work out in the end.

I'm attaching a snapshot of what I've managed to accomplish so far. It's nothing fancy but it might help someone trying to make buildings BI-style. Ignore the mapping on the sides of the windows and the windowsills (and the fact that some squares don't line up), I've only worked on mapping the elements as repeatable squares so far. I used the copy-UVs method from the single window on the ground floor to the identical single window on the other side.

northhouse101.th.png

Edited by cctoide

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