Model a city street?

[mental]

depending on how large the scene is... i would take a queue from what the game folks do: prelight the scene.

i think you can find a tutorial under the how to's section on www.alias.com

other than that search the forum for 'prelight' you should be able to find more tips that way.

hope that helps
-mental :surprised

[eric3dee]

great thanks!
That will certainly help out on render times. Now about the modeling approach... anyone have any suggestions?

[mental]

well again, the benefits of pre-lighting go along with the concept of letting most of the scene's detail be in the textures and not the geometry. through the use of pre-lighting, bump maps, and even displacment maps you can add details that would be too heavy to include in the base geometry.

take a look over in the cgtalk gallery and also the finished projects forum... there you'll be able to see the wireframes for most of the environments. you'll notice that lighting and texturing comprise 75% of the piece and the intelligent use of mostly low density geometry forms the base.

as you look at other people's environments pay attention to why they did things the way they did. by example would probably be the best way for you to understand how to setup a complex environment.

[dmcgrath]

As a tip, the prelight video is a .swf file. That mens you can go into your internet cache folder and pull it out of there. Then you can just play it in IE as many times as you want, and you never have to d/l it again.

[BigSky]

Ilora, Melbourne have a nice look into the process for their monaro commercial:

http://www.iloura.com.au/work/Monaro/Monaro_making_of/building_cities.htm

[bmoney]

Storyboards... If you lay it out and know exactly which parts are going to be up close to the camera then focus on their detail and the other areas can be less detailed. Also think of what type of shots you need. A few big tall buildings will block out the need for excessive detail in the background which may not be vital to the scene.

Brett.

Also, If the buildings aren't going to be based on existing locations, choose buildings that have less detail or reflectivity and effects needed which chew render times.

[eric3dee]

Thanks again-- these are all great tips. How about modelling/texturing? I'm more comfy with polys personally, but for streets and sidewalks and such, would NURBS serve a better purpose? Specifically in terms of texturing-- do I go with extremely hi-res planar mapped textures (specifically focusing on the details of the shot, or do I go with a more procedural/tiling approach and break it up with stain maps and such? I'm going for a more painterly look to the whole thing really (specifically the look of the 3D/2D backgrounds as seen in the "Animatrix" "Beyond" episode. Again, thanks sooo much for the suggestions and sites.:thumbsup:

[Bonedaddy]

I have a similar project going on right now that's a flythrough of a Hollywood Hills-type area. My suggestion to you is to use extensive camera projection. Go out and find elements of stuff you would like in your scene, put them together in photoshop, and project that through a camera onto simple geometry. You can do one projection for each building, if that's the LOD you need, or one can suffice for all the bg stuff. That will free you up to hand-craft the ones closest to the camera. Making dozens of high-quality buildings will just kill you.
Also, since you're going for a painterly look, you can paint over the projected photos in Photoshop (or run some filters, if you're lazy) to give it the right aesthetic you're going for.
Will probably require quite a bit of Photoshop and compositing work to get all the disparate elements to seem like they work together, but I think it'll save you a lot of time in the long run.

[edit]: And, oh yeah, get some storyboards. For the love of god, get storyboards.

-J

[antweiler]

Polys.
check http://www.learning-maya.com/tutorials.php maybe you find a city tutorial there.
I recommend to organize your scene into display layers, to prevent too slow screen refresh.
hoipe this helps
antweiler

[eric3dee]

Making dozens of high-quality buildings will just kill you.

Amen to that brother. The projection idea is pretty good too-- I had sorta already planned on doing that for the far background elements, but I could probably also get away with that for some of the foregrounds as well, since most of my Camera motion barely moves (no fly-thrus thank goodness!)

antweiler--I checked that site before, but surprisingly have found a large lack of detailed (from-scratch) city environment modeling tuts.
Bonedaddy- for your project, how are you going about modeling texturing the street? (Nurbs or polys? UV or projections or procedurals?)

[Bonedaddy]

Originally posted by eric3dee

Bonedaddy- for your project, how are you going about modeling texturing the street? (Nurbs or polys? UV or projections or procedurals?)

I find texturing NURBS to be quite the black art, so I am a strictly poly person. I will likely use NURBS curves to block out the path, then birail with an output of polys or subDs (it's DV output, so subDs aren't SO necessary).
For the texturing, I'm planning on just matching up my models as closely as possible to the camera projection, and tweaking the UVs until they fit. After that, I can move it around, twist it, etc. as I see fit.

Although.. here's an idea that just occurred to me, I'm about to run off and try. How about doing a birail with completely straight curves, like racetrack. Basically looks like a rectangle from above. Output as polys, UV texture it with a road texture -- all this is simple. But don't delete the history -- you can go back and use the NURBS curves forming the birail to curve and deform the textured road as you would please. I -think- that would work... ^_-

-J

[eric3dee]

great idea Bonedaddy. I will try this on Moday. Thanks. Still, I wonder how big of a texture I will need to look good up close on certain parts too. Hmmm.....

[Bonedaddy]

So my idea did work, my only thing now is how to keep the road's width constant. Basically, when you move the points of both curves around, the width of the road varies.
NURBS has a built-in option to make a curve that is of a constant width offset from another curve (handily enough called offset curve), but this only happens at creation. Thus, editing it by hand is not really doable.

I see several solutions:

1) Come up with some auto-updating offset curve script, so that the dependent (offset) curve would update whenever the "parent" curve is tweaked (probably pretty hard)
2) Make a script that would run through some code and create a road based off a single nurbs curve (wouldn't be too hard, but not too easily edited in viewport).
3) Rig up some skeleton system for the road, maybe using IK spline. I tried this, but it didn't really work. I don't know much about rigging, however, so I am probably doing it wrong. Hrm.

-J

[eric3dee]

Bonedaddy-- Wow- sounds like a problem. Fortunately most all my roads are straight (Thank goodness.) Appreciate the help.

[eric3dee]

ok-- I sorta ended up doing the street my own, easy way ;) I painted a fairly hi-res tilable street texture (1024x512- this is only going to video res anyway) within Photoshop, created a poly plane in Maya and applied a normal color projection to it with my file. I then extruded the edges of my poly plane (once I had shaped it as necessary) to extend the road and the texture tiled fine. For curves and what nots, I just created a new plane and did the same thing, and then applied a Bend modifier to it and later combined all the roads together using Poly>Combine. I can now tweak topology or add topology as needed without screwing up my street texture. For intersecting roads, I simply intersect the geometry with the new crossing roads very slightly overlapping the main road, and then apply a new texture with an alpha fade on the end where they meet. I'll admit that its a jerry-rig, but I'm pretty pleased with the results.

[robin]

Im not sure if this link can help you since its not totally a " fairly detailed city street " but someone asked me something similar in a other thread

made in Lw but easy to make in Maya

i hope it fits your needs.


http://stage.itp.nyu.edu/vreal/painting/


-R

[eric3dee]

yes- I have seen that tut before--- not bad, but it seems to only work for one particular Camera angle with the detail only being in that one particular building. Good concept tho, with some great ideas presented.

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