hi, I’m getting ready to create my first exterior rendering, and I’m trying to get my grass texture down before moving on to the full scene. I’m using RC3, and I’m trying to use the physical camera with Vray Sun/Sky. I haven’t had to use Vray Displacement mod before, and I’ve looked over a ton of threads and tutorials (this one was the easiest by far:
That link is where I found the bitmaps that I used in the scene below. I’m also trying to get the hang of Onyx Treestorm, but that doesn’t worry me as much as my grass material. My biggest beef with it right now is that the displacement looks more like carpet than grass. I’ve played with the resolution in the displacement mod, but it’s starting to tile for some reason. Can someone please recommend how to adjust my settings to improve this? I don’t completely understand how the displacement map gets applied; is it controlled by the UVWmapping mod I have beneath it in the stack? Would this be good enough from a bird’s eye or a typical camera height (5’-0"?) Thanks.
What I tend to do for grass is place the displacement map in a slot of the grass material (eg then bump slot) but uncheck the box next to it. Then I drag that into the map box in the vray displacement modifier and select instance.
okay, sounds simple and makes sense. would you generally use a bitmap for the diffuse as well? and, if so, would you necessarily use the desaturated version of the diffuse map for your displacement map? (that’s how I used to do it for the bump map, but I really haven’t had to make anything look organic before.)
I have played around with VrayFur objects a bit following a few online tutorials designed for making grass, but I haven’t been too successful, and I’m not sure if this is the best situation for it. Here are two VERY preliminary scenes. The camera angles and the basic geometry will stay the same. You’ll notice in the eye-level image that I’m getting some weird discoloration of the closest median; doesn’t show up without displacement modifier on. Is it worth using VrayFur or VrayDisplacement for either of these shots???
Thanks for the link; that’s absolutely what I’m dealing with then. So what I was hoping to be a relatively easy mapping/rendering fix is turning out to be a major remodelling effort. I do very little modelling in Max; everything has come straight out of AutoCAD or SketchUp. I know that I can import my roads and flat landscaping from CAD into Max as splines, but then what should I do to make them usable with VrayDisplacement? I really have WAY too many curves to create all my own polygons. Should VraDisplacement mod work if I simply extrude the editable spline or convert it first into a editable poly? I am keeping everything flat which I assume makes all of this quite a bit easier, but I’m still a bit lost. I know this is more of a Max question, but if anyone can point me in the right direction I’d greatly appreciate it (while I search the Max forums…)
One other thing, I’m trying to learn how to use the unwrap modifier and understanding UVW’s, and I installed the Textporter plugin. What’s the basic workflow I should follow so that I can unwrap my roads and then add some texture to them in Photoshop? It’s such a big scene; is this a horrible idea? I was going to add lines and some wear-n-tear.
Again, thanks for the help, but I could still use some more obviously.
What I would try is with the splines.. shape merge them into a BIG plan with lots of subs.. then delete all the surrounding mesh.. or you could do some fancy boolean operations so that basically you get a big plane with lots of nice square polys thats clipped out to tbe the shape of the grass. then dispalcement should work nicely.
As for the unwrapping deally, depends on how close you get to the roads, it might be wiser to cut up the roads and use smaller higher resolution maps for each piece rather than one massive one for all reads. But if your only doing aerial shots then the map doesnt need much quality.
thanks, i will look into those suggestions (first I’ll need to look UP how to shape merge and better understand how i would go about using boolean operations on this.) the two crappy renders at the beginning of this thread are basically the shots i’ll be working towards, so I will definitely have one shot very near the road and near some grass, so i would like to get some better looking texture on there. i know i’m asking a lot, but you guys keep giving me answers, do you know of any tutorials that would help me learn how to better utilize photoshop when preparing maps for max/viz? i know how to reorient and adjust some of the levels, but i don’t really know how to go about painting them to look realistic. i’m sure this, like everything else in CG, is an artform, but it’s high-time i learn the basics of it.
As for better PS usage, well it depends on what you are aiming ti do.
If you post up some examples of textures you want changed and what you want done with them I can give you some suggestions.
With your shapemerge and boolean issue, they are rather easy to do. They are both in the compound objects in the create object pull down menu.
With shape merge it basically prints a spline onto a mesh.. then you just need to delete the un-need polys. And with boolean you would need to extrude the spline first so you get a solid mesh of the bits that you do or dont want… then just a matter of a boolean or 2 and it should be fine.
If you would like you can upload just the splines for the grass/road areas and I can take a stab at getting a nice mesh for you and tell you how to do it.
Sorry for the late response, time differences and all that!
I do use a bitmap for the diffuse, but a different one for the displacement. There is a nice video tutorial on Evermotion which includes a couple of maps you can down load.
Hehe -- you mean my tutorial on VRay-grass with displacement then?
Another problem occurs - in my cases - if you increase the tiling-value of the displ.-texture to a very high value, e.g. to generate small gras-branches in a huge area.
Maybe VRay-Fur is a better choice in your case when rendering closeup-scenes
