Creating Realistic Rocks with V-Ray - part 1

Part 1 of this tutorial shows a way to create very realistic looking rocks that can be rendered far away or for very detailed work. After failing to find a decent tutorial online I decided to start experimenting and I came up with this. I already knew how to make decent looking rock but I needed a way of generating loads quickly for a very rocky landscape. In Part 2 we are going to distribute those Rocks on a large scale using Vray Mesh Export and the Advanced Painter Plugin.

You need. 3ds Max, V-Ray, and Francois Mourlevat’s Asteroids Generator Script and the texture inluded in the scene file which is a modifies version of a texture I got from CG Textures.
There is a video that shows the process at the end of the tutorial.

1

Create a Rock using Asteroids Generator Script using the settings below. You can have a mess around with these parameters. It’s ok to delete the rock that appears when you open the script. The settings I have used are good for the jagged rocks I need. Hit the Creation Button.

2

Apply a Displacement Modifier to the rock. (Note that this is not Vray Displacement Modifier.) I used a strenght of 180mm. Select Shrink Wrap. Make sure you Load the Rock bitmap into the Map box as shown in the expanded view.

3

Apply a Turbosmooth Modifier to the stack. An Iteration of 2 is fine. I would leave it at this if you are going to be using a lot of rocks

4

Open the material editor and create a VrayMtl. Load the same bitmap we used for the Displacement Modifier into the Diffuse Slot. We are using the same bitmap for everything. You will see in the expanded view that I have dragged it down and ‘copied’ it into the Bump Map slot as well. I also added a Falloff Reflection as shown. This creates a realistic look to the rocks by adding a nice reflection to the perpendicular and parallel angles. Remember, Everything reflects! You can take the Reflect amount down to 40 or lower and turn Refl. glossiness down to 0.5. You can mess around with these levels.

5

Apply the material to the rock and add a uvwmap modifier to the rocks modifier stack. Choose Box as the mapping method.

6

I decided at this stage to add a Vray Displacement Modifier below UVW Mapping using the settings below. Copy the Material in the Bump Slot over to the Texmap box. Amount 5.0mm, Resolution 300 and Precision 5. Nice and low for rendering. Note: to speed up the rendering you can use 3D mapping, instead of 2D mapping, for a slightly different, but faster result.
At this stage hit render to see what your rock looks like. Note: To get some light in the scene, change the Environment slot to white if it’s not already.

7

Using another script called pivot placer which is part of Blur Scripts I placed the pivot to the bottom centre of the rock. Hit right mouse button on the Z: Position spinner arrows to get the rock on the floor. blur scripts link http://www.neilblevins.com/blurscripts/blurscripts.htm

8

Using the Asteroids Generator hit Creation to create more rocks. Each one is a different seed. Again, place the pivots of each one to the bottom center Hit right mouse button on the Z: Position spinner arrows to get the rock on the floor.

9

Copy the original Rock’s Modifier Stack to each new Rock as an Instance, and Apply the Rock Material to each of them as well. You now have new rocks with exactly the same modifiers and materials applied. Make as many as you need.
If you are finding things are starting to get heavy for your PC then turn Iterations in the Turbosmooth Modifier down to 1. Essentially we want to create these rocks for distribution using Vray Mesh Export at a later stage so a higher Iteration will be fine. But for this exercise you can turn it down.

10

So we have a number of Rocks, all different, with copied instances of the modifier stack, and the same material applied also.

11

Create a Vray Plane and apply a basic VrayMtl to it.

12

Create a VraySun and click yes to add the Vray Sky to environment.

13

Create a VrayPhysicalCamera and position it as shown. Click image for Camera settings.

14

Render Settings. Note: Just decrease or increase the Noise Threshold Amount in V-Ray DMC Sampler to change render quality. Note: The settings in the incuded scene file have Brute Force GI and camera Depth of Field (DOF) enabled, and this can take a while to render. To speed up the rendering you may want to try using the Irradiance Map GI method instead, and turn off the DOF in the V-Ray camera.