We are producing animation and still CGIs of a large business park. There are a number of buildings (around 20-25) and associated road system. I’m trying to work out the best way to create the roads. If they were constant widths (and only one of them), I could simply draw a line down the centre and ‘sweep’ a rectangle along it to create both the geometry and the UVW mapping. However, the road continually varies in width and there are side roads that ‘peel off’ the main axis road.
Anyone have any good suggestions on how to deal with this?
I guess I could take a high resolution plan render of the road and then paint a huge texture map in photoshop, but the texture would be enormous to hold up to close-up views.
You could probably do what you suggested and then mix/blend to a different map for closer shots. Maybe you could setup a standard asphalt texture for the road and maybe use vertex painting to create shading for different areas…maybe use the distance texture for the edges to create some noise and then draw the lines etc using geometry and alpha maps.
One big huge tiling map for the asphalt, make the entire road geo using splines and make all the markings as other physical objects using sweep. You could use the same sweep paths as a source for spline mapping on the roads too to add in junk / dirt along the edges.
you could use railclone…the other more elaborate method is doing a gradient ramp for road lines and mixing that through the composite texture as mask to drive the detail. Also tillable texture alone doesn’t really do the job. It depends on if visible tiling is ok, but typically creating two tillable ashfalt textures and mixing them through a procedural noise will give you a pretty good range where you wont see the tiling up close and at a distance.
That looks good. My only problem is with roads that have varying cross sections. Sweep objects don’t allow you to scale do they? I know loft objects do, but that seems a bit ‘old skool’!
I usually use something along the lines that joconnell suggested using sweeped lines for the markings. For the road texture, I use a large (~8k) painted map for the “mix amount” map. For the texture slots of the mix map, I use a nice, non-tiling asphalt texture as one slot and the other slot is usually the same texture just a lot darker and with slightly different UVs and rotations. Since the mix amount map is just blending between the two asphalt textures it can be somewhat low res (compared to the area the map is covering) and I just start adding dirt, seams, streaks etc using layers in photoshop. This technique holds up pretty well at different scales (aerials to street level) and lets me get the map done pretty quickly without having to paint an enormously detailed map. See examples below (the renders are crops of the same area about equal to the red area on the map).
That looks very good. So essentially, create the geometry via whatever means, then use either sweep objects or railclone objects for dotted lines/yellow lines etc and then use one huge UVW map in the top viewport that covers all of the road. Then, create a ‘mix amount’ map (around 8k x 8k or whatever suits the size of the UVW map) and just paint that in PShop with bits of dirt etc. Seems like a good plan. I guess finding the large, none tiling asphalt textures is crucial. I have a couple, but not very big really. Care to point to any online libraries of this? I’ve done many searches over the years, but its always been something I’ve struggled to find.
Yeah that’s basically it (like I said it’s pretty simple). For the asphalt map it’s not really that big, just 15’x15’. First guess for a good map would be cgtextures.com. You could also use a mix map controlled with some noise to make a non tiling version of a stock asphalt map. Also, I sometimes use the same material (with the mix map) just color corrected white or yellow for the painted striping - it helps to break up the pristine colors (I don’t think I did it on the above images though).
Do you paint the streaks cracks etc on the “mix amount” map then? Or is it painted on the asphalt map? I’m confised on which layer you paint it. I’m geussing the ashpalt layer, otherwise how do you get the detail of the cracks on a low ress mix map?
the crack map it’s a mask, so you can copy the material that you have for the asphalt but darker with the crack mask and bump, they could be in different mapping channel to control the scale if you need it.
First off, stop calling it a “Crack Map”. Somehow that just sounds wrong.
But Flino’s right, it’s just a mask so all of the detail in the cracks and dirt just comes from the darker asphalt map. This isn’t a perfect solution to create the most amazing road texture ever, but it is a quick way to get some decent detail in a road over very large surfaces. IMO, it’s just enough detail that someone looking at the images won’t notice the street at all (due to too much detail or too little) but will focus on the buildings, which is what they’re paying me for anyways.
I use the same method of painting a big map to cover the whole area as the base map and then overlay with composite map in multiply mode ( I don’t use mix-map for this). Good thing is that maps for cracs, dirt etc.. can all be in greyscale or even index mode (less memory consumption). If you need to colour grade it just add another layer in composit map and change mode to colour. For close up shots I always do more detail set up with road surface, lines displaced, glossed etc…
Great news is that now in Vray 2 you can fragment those big maps so not to clog your memory.
