Breaking the skate park up into manageable pieces would be the way to go.  This will allow you to texture each piece (structure) in the skate park independently of each other.  Also, don’t forget since you are adding graffiti, that would promote the forms as being somewhat old, having wear and tear.  Don’t forget to add some dirt and grunge to the materials as well.  Don’t be afraid to let the dirt and graffiti overlap, add cracks to the concrete also.

To keep in mind while modeling the skatepark, keep UVW mapping in mind, since you say you are new to Max.  Maybe put a material with a checker map in the diffuse to keep track of what is going on with your mapping.

Calvin Clayton, Jr.

Would you model the cracks or incorporate them somehow into the materials? Is there a default checker material somewhere within max or would I need to create one in PS?

... also, to avoid being able to see the tiling effect of the concrtete material is it best if I use an as large as possible concrete material image?

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I would model some cracks and incorporate others in the maps.  If it is a crack on the corner, I would model it; however, if it is within a wall, I may add it to the map.

there is a default checker map that you can use.  In your material select the empty box next to diffuse, a dialog box will open, there will be a checker map you can add to the diffuse channel.

There are numerous methods to avoid seeing the tiling of a map.  Size of the image doesn’t matter if the map itself only covers about three square feet of concrete a higher resolution image will still only be three square feet of concrete.  Making it larger via UVW would make it out of scale.  Obviously, you can make it larger, but only up to a point.  If you only have a single concrete image, you can use nested mix maps to avoid tiling.  Adjusting, brightness, contrast, etc.  while using a noise as a mask.

Personally, I think modeling the skate park is your first concern, then mapping it.  I wouldn’t worry about the tiling concrete at this point, can be fixed later.

Calvin Clayton, Jr.