believe it or not, 3d world studio is an upgrade(major) of CShop 4. Leadwerks just gave it a different name. they both have very similar layouts except 3d world studio just offers more. Well the majority of my maps are indoor but im sure designing the maps revolve around the same principle.
what i do for designing levels is:
- Planning
- What is the purpose?
- what makes it stand out from the rest?
- figure out a reason why you cant just add it
to a previous level
- what is the look and feel or ambience?( you want to extract
feeling and emotion from the player)
- i.e. GTA4's last island feels crummy and wastelandish. why is
that?
- your level/city should have a gimmick to it...something that
the player will remember your map by
- i.e. GTA4's "times square", railway tracks on the first island
- Design
- Draw out a rough sketch of the layout on paper and try to
visualize the flow and any noticeable problems
- what is going to happen in the level? scripts? storyline?
- write down what items, enemies, or entities will be needed and
where
- write down what meshs or other objects you might need.
- i.e. im planning out a new game that takes place in a deserted
and near-destroyed city so some prefabs i might need are
street signs, highway signs, garbage dumpsters, street cones,
street barriers, etc.
- Execute
- layout the simple geometry of the level or the flow
- add some lights as you go
- start texturing your geometry
- detail,detail,detail
- make sure most buildings look different architectural or
geometry-wise.
- add a few different textures to it
- put in interesting architecture
- add prefabs like the ones i mentioned
- add your entities and fine tune your light settings
- create high resolution lightmap (optional)
thats pretty much how i do it. for prefabs you should probably use a 3d modeller and import the files into 3d world studio. there are some free ones out there but i prefer milkshape 3d ($20 USD). Very reliable, flexible, and has a solid easy to learn layout for modelling. just food for thought. I can try to give you an example of what i mean but give me until the end of the weekend or something because ill probably be starting from scratch.

if you got questions just ask. oh ya, i posted my own screenshots a couple of pages back on this thread. forgot the page and not sure if it is still up but its worth a shot im sure.
edit: im on page 16 about the middle of the page. it was a simple hallway i put together...no complete level unfortunately
Homey
"I don't think so... Homey don't play that."
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