So, I tried different combinations of so many settings to correctly display the building with transparent vertices. scene.useOrderIndependentTransparency seems to work well, but it sometimes causes the same artifacts. Here, too, the room inside is incorrectly displayed
Once you get the solution, you can hand it over to me, I will gladly take it
Else, I can recommend a few things. Make a merge of opaque objects only, keep all alpha blended meshes separate. use alphaIndex to order meshes transparency. Don’t use forceDepthWrite but instead use (on your alphablended meshes only) needDepthPrePass. Use it only when you are cumulating transparency (a window through a window) and use it in combination with the alphaIndex. Eventually have 2 materials (a clone) to allow for specific settings. The rest is a game of patience (similar to a puzzle ). Else, you can still try to use OIT but it comes with (a number of) limitations and following those on something already done can also become as tedious as taking the path of a custom/manual ordering.