Which Details to Keep?

danshewan

Hey guys,

I decided it was about time to get back to work on my St Paul's Cathedral project after an extended hiatus, and I have some questions that hopefully someone can shed some light on.

This model is intended to be used as an in-game environment asset.

I've created the high-poly mesh first. Right now, it's about 170k triangles in total, and I'm faced with the task of laying out the UV's. So, with that in mind, I've got to create the low-poly model. My question is, given I've not worked this way before, which structural details can I get away with using a normal map? My experience of normal maps has been using them for surface aesthetic detailing, so I'm a little hesitant as to what I can strip from the high-poly.

Here's a viewport shot of the high-poly mesh:





As can be seen, there's a lot of structural detail that I've modeled in, but for the low poly version, should details like the windows, frieze and columns be left intact? I'll still need to go into ZBrush and add surface texturing to the stone, but I guess I'm wondering just how low-poly the in-game mesh can be, and how to go about deciding which details can be normal mapped.

Thanks in advance for any advice / C&C / etc.

Ben Apuna

Just break that sucker up into modular chunks, that way you save on overall texture usage and the instanced polygons won't kill performance in whatever engine you decide to put this in.

It's a little hard to see what you can specifically get away with here as you picture is a bit small and all you wires are blending into black globs...

For anything the general rule is if it doesn't have a significant impact on the silhouette of the object then use normal maps for it. A lot can be faked, try to think about how the player camera will view the different parts of the building. The further away something is from the camera then the more you can get away with just using normal maps.

If you haven't already done it be sure to check out the Environment Modeling FAQ & Resources thread.

Hope that helps.

Xenobond

You mention the intention of placing this in-game. What kind of game were you thinking of? That would also help determine the level of details that you'll want to keep.

If it's a FPS, you'd want most of the detail at the players level. So starting with the 2nd floor, you'd keep most of the detail on the parts that define the important shapes. The roof and toppers could be simplified much more.

Take some screenshots from whatever would be the players perspective, and see where you can optimize from there.

Definitely check out that FAQ posted above.

danshewan

Thanks for the link to the FAQ, guys - I had checked it out, but thought some more specific pointers would be useful.

And yeah, I should have mentioned that I'd envision it as part of an FPS game, similar in style to Fallout 3, which has been a major influence on me and the kind of work I'm striving to create.

Thanks again.