The rug in our scene is created from a chamfer box with the bottom half deleted. This allows a slight curvature to the rug itself. The rug also has fifty segments in both the length and width.
Option 1: VRayDisplacementMod
The first technique uses the VRayDisplacement modifier on the rug mesh itself. I used the 3ds Max Cellular map to drive displacement. The only adjustment to the Cellular map was the size, set to 0.001.
1. In the Command Panel, choose the Create tab.
2. Be sure the Geometry button is selected.
3. In the rollout, choose V-Ray from the list.
4. Finally, select the VRayFur button.
This series of steps creates the VRayFur object, and you will instantly see strands of fur on your selection.
Method 2 (my preference):
If you have the V-Ray Toolbar open, with your object selected, simply click on the VRayFur button that has an icon of what looks like grass. Easy enough.
As you can see, the default settings are less than ideal. With just a few tweaks, however, we can achieve the desired effect.
This one is self-explanatory. To start, I changed the length from the default of 1'3" to 0.125". We will discuss various lengths again shortly.
Here, I adjusted the thickness from 0.2" to 0.02".
This is the one value that doesn’t change in real life, so I left it as the default setting. Of course, if you’re going for a unique look, feel free to change this up. That’s why it’s here!
For now, I’m leaving this as the default value.
Taper determines how thin the strand gets as it approaches the tip. The default is at 0.0 with no taper, while 1.0 means it goes to a sharp point. For this exercise, I adjusted the value to 0.85.
For now, I won’t adjust any of the variation amounts, but we will look at the way Distribution works.
This example simply shows the adjustments in Length of the strands with the above settings already described. As you can see, the rug becomes darker as the strands become longer. This is simply due to light getting trapped in-between the strands. The ideal length really depends on the look or style you are trying to achieve.
There are a few other styles of rugs that we will explore, along with the settings to achieve each style.
Rugs come in an infinite array of shapes and looks. Some are fluffier while others have a tighter, curlier pile. To achieve the latter, V-Ray has a curl property. When turned on, this tool allows you to specify the details behind the fibers’ curls. Here, I set the Curl radius to 0.05. The length of the strand is a factor for the way the curl is displayed. I also set the Number of curls to 4. Note that I adjusted the bend to 0.0 to keep the strands straight and just allow for the curl to control the bending.
The clumpy settings enable portions of the rug to grow in a specific direction. V-Ray allows you to control specific properties to be driven by maps. In this case, I used a combination of a Cellular map with a Noise map to regulate the direction.
Direction in this case is driven by the RGB values, with each color as a different direction.
Red: u texture offset
Green: v texture offset Blue: surface normal offset
These parameters require a bit of trial and error, and you can achieve some very interesting and surprising results from simply adjusting the colors and values.
In each example above, you can achieve some unique, controlled results, but as the strands get longer there is one problem that arises. The fur has no regard for other objects in the scene. This is evident when there is a piece of furniture that the fur will grow through or over. An easy yet powerful solution, however, prevents fur from growing where objects stand in place.
Without Distance Tex
With Distance Tex
Just like the Initial Direction Map, there is an option called Density Map. This field specifies which portions of the rug will grow fur and which will not. Simply put, a greyscale image will determine the density of the fur in that area with white being 100% dense and black having no fur. Cleverly, V-Ray has a map called VRayDistanceTex that allows you to specify objects in the scene to drive the Density Map.