Topology Help - 50 Arched Windows?

I’m hoping proficient modelers can point me in the right direction here.

Goal: model a large room with tons of windows, to import to a game engine for VR use (Unreal).
Ideally, it’s as realistic as possible, but budgeting polygons to maintain decent performance.

I was trying to use Archimesh to easily make the windows, but the booleans really mesh with the geometry. Can I still use it and then struggle to clean up geo after? Should I model from scratch?

I can imagine modeling a basic rectangular room, and I am comfortable enough to make a low poly window somewhat similar to the Archimesh one – What I’m confused about is how to combine it cleanly without boolean etc.

I found this great post: How do I cut out an arch from a wall? Where @Photox shows a really nice clean technique for arches, but I’m not sure if that would apply to a room with 50 windows!

I’ve attached a number of screen shots of the room I"m trying to emulate, and my current disaster, plus a screen grab of @Photox’s work in that thread.

Any tips, either specific or general are appreciated :slight_smile: :smiley_cat:

2020-02-26 14_26_02-Window

depends on how you want it
high res or min low res and look good using UV images

if you don’t need subsurf then might be easier

but if you use subsurf then don’t use Ngon won’t render nicely

also you could simply UV map alpha image of a rounded arch

happy bl

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I like to use this one. Is very modular and if you need to subdivide is easy to add control loops.

Thanks @RickyBlender Question: how would I know if I need a subsurf modifier? I can imagine if I was modeling a head, how the modifier would smooth out geo, but I’m fully sure I understand how it works on more boxy geo like architecture. Can you describe how to ‘UV map the alpha image of a rounded arch’ a bit more? Sounds really intresting. I understand the trickery that comes from UV maps and depth, but not sure exactly what you’re picturing.

@bloox64 That looks really nice… Did you make that?
When you say ‘this one’ do you mean that approach / technique? That looks really helpful and I’d like to try my hand on it. Any suggestions?

Also, do you have any suggestions on how you would approach making 20 of those in a wall?

Yeah I made it. Basically extend the window edges up or to the sides, this way you don’t have more than 5 connecting edged on the points and can later weld the “modules”.

Just delete the faces of the wall keeping the edges and then extrude them up and then to the sides. If not all of the walls have windows just keep extending the faces.

Althought this is not exactly as clean as I’ve said, is still fairly clean.

if you got a arch UV image with some alpha
one way is to select some rectangular area on your mesh and create a new material then unwrap it and add texture image for that rectangle.

this should give all the colors of the image but only valid if seen from far away
you could add a bump map for some parts of the arch or roughness

happy bl

Appreciate the reply @RickyBlender - Struggling with some basics here though so still lightly beyond my noob skills :wink:

@bloox64 that looks like really nice geo! Unfortunately I’m pretty stuck here even on basic Modeling. Maybe you can tell me where I’m going wrong in my approach.

  1. I created a cube and turned it a large room size rectangle
  2. reset the scale
  3. on bottom underside, did an inset of .2 meters, then extruded that up to .2m shy of ceiling
  4. started to add loop cuts horizontaly and vertically to even begin just square windows.

#failed when the loop cuts of inside didn’t extend to outer wall, so cant cut / bridge window holes even square.

Any tips on the basics, or any suggestions on how you learned would be appreciated.


It’s way easier, take a look at this gif.
Make a plane and create a hole with a boolean, apply the boolean and delete the faces only, and the remaining edges. Then extrude them like this, make use of snapping (set it to point and active).

After all that, select all and in vertex mode alt + m and merge by distance to remove doubles.

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Hey that’s a really great gif! Thanks for taking the time to show me how to do it :slight_smile:

Can I ask about your screen capture to gif workflow? It will be great to be able to do the same thing if I’m ever helping another person.

You’re welcome! I also had the same doubts back when I did that and I thought that was the easiest solution to model AND specially, edit and do changes to.

I use ScreentoGIF https://www.screentogif.com/

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Love that! Thanks for the help and for sharing :slight_smile:

Hey @bloox64

I’m still pretty stuck on this room modeling. Would love it if you’d take another look.

I’m going back to Archimesh to make windows, hoping to apply the boolean after and remaking the topology in the technique that you showed (deleting faces not edges).

The catch is that the booleans are acting up (see in images). Maybe it’s because I’m duplicating windows? (each has a window mesh, a ‘cut hole’ mesh and a group, and I’m having to Control-C /V all 3 to make it copy… Just duplicating / copying the group doesn’t duplicate the hirearchy.

Any suggestions on how you’d got about modeling a room with many windows like this appreciated :smiley:

2020-02-28 14_32_11-RightWhale_1 - Unreal Editor 2020-02-28 14_32_06-Blender_ D__WhaleProject_BlenderHome_New.blend 2020-02-28 14_31_58- 2020-02-28 14_31_38-

Hi, I’m not sure how you’re making the room exactly, but if my guess is right, you’re only making one wall AND you probably still want those windows still be editable with archimesh?. I’m not good at managing big scenes with hierachies since I haven’t done many of them as well…

What I would do would be having wall sections with the good topology, that will be later duplicated, that way you already have holes and will be a matter of placing (aligning) them to the windows and later join them in one abject.

Here’s another capture of my project which is similar to yours… As you see, the orange part is the only geometry, then I use array modifier.

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Bmesh cannot make Ngons with holes, so whenever you boolean you see those edges with the very oblique angles.

To prevent it, split the face(s) horizontally as preparation (where you want your row of windows), and the boolean operation should give you a clean mesh (because there would be no splitting of the surrounding face). Since this is architecture, you could probably get away with just a triangulation modifier unless you need specific patterns visible in the texturing.

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Thanks for the support guys!

@bloox64 - that’s a really nice image!
I don’t need to have the windows editable… I just need to make the arched and flat tops versions and then copy and paste them everywhere. Your geo is really nice :slight_smile:

@Ace_Dragon - thanks for the help. Can you explain a little more (I’m a noob).
When you say split faces, do you mean adding a horizontal edge loop through middle of windows?
Can you also explain how you would use the triangulation modifier? Do you mean before or after the boolean? I will be in Unreal and baked lights later – but no specific texture, just a white wall color with shadows.

The highlighted edge is the split made before the windows were embedded.

The triangulation modifier allows you to turn your mesh into triangles non-destructively. It shouldn’t matter if you’re exporting to Unreal since most exporters give the option to apply them automatically. Because it is a modifier, it doesn’t matter when you add it.

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hey this is SUPER helpful! Thank you for that :slight_smile:
I’m going to try this right now!

Hey Ace,
The horizontal edge loop has really helped me made some progress over the last 12 hours.
One thing I’m having trouble with though:
When I applied the booleans, about half of my windows don’t complete the geo from wall to the other…

That means that I have to go in and select both sides of the wall splines one at a time to fill (see images). If I alt-select both splines, it doesn’t fill cleanly.

Any suggestions on what I might try to get the booleans to be more consistent on remaining geo, or faster / easier cleanup of missing geo?

Right now I’m going face by face to repair… Will probably take an hour or two.

edit while FILL doesn’t seem to work for the edgeloops, bridge edge loop function in right click menu seems to reduce my painfully slow approach of two edge select one face fill at a time :wink:

Hey @Ace_Dragon
I’m having geometry glitch issues in Unreal when I bring the model.
See how it looks in Blender, vs in the game engine?

If I put a triangulate modifier, it definitely changes the geometry… Is this what I should do before exporting for the game engine? I know you suggested the modifier, but just want to confirm this is what you were suggesting.

p.s. @bloox64 I guess I should be using your technique!! If I can’t get this figured out I will and delete wall faces and extrude vertices up to ceiling like you show in your gif