This is what my modular kits look like:
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Each wall of mine has several possible combinations: Size A, with door, without door, with window, without window, with big window, without big window, etc. Then repeat for Size B, Size C. Pillars, external and internal corners, straight or round corners, different degrees for the round ones, and so on. I waste so much time doing that, that back in Blender I even tried to create a Python script to help me, but never managed to achieve something that was actually useful for me.
What technique would you guys recommend for me? Is there any video tutorial or course that I can buy on this subject? I found a lot of procedural cities and building generators, but they rely on building blocks, like modular walls. What I want is to generate that base geometry and create a whole base that I can decorate/modify later with my stuff (like moulding, greeble, etc).