Shadow Catcher material in the New V-ray for Sketchup 2.0
**New: Added settings dialogue example for Vray for Sketchup 3.0 beta**
One of the materials that’s been sorely lacking in the previous versions of Vray for Sketchup is a “shadow catcher” or matte material that can define a transparent shadow in a scene. This is something very useful when you want to add an environment background under a rendering. The resulting shadows help integrate the model into the scene image very effectively.
It’s pretty simple now to add a “shadow catcher” material with the new Vray 2.0 version. In the vray materials editor, you need to right click on “Scene materials”, select “Add new material” and then select the one at the bottom of the list: “Wrapper Material”.
Here is the properties window for the new material you’ve created, now you’ll want to change the following properties:
Here are the same settings as they should look in Vray 3.0
1. Define and select a base material (over a grass background for example – use a grass material) This material will affect the GI – so you’ll get some color reflection
2. Change the alpha contribution to -1
3. Check all the boxes for Matte, shadows, and affect alpha
4. I reduce the GI amount so there is less color reflected into the scene. If you use a neutral color, you may not need to reduce this value.
5. You can lighten the shadow as needed by changing this “shadow brightness” value.
Now you can apply this newly created vray material to a plane that you’ve made under your scene. Make sure it is applied to the front face of the material. If you are looking at the back face of the plane, the matte material will not render as expected.
In the example rendering below, I’ve placed a background image in the Environment slot using the newly available “Screen” mapping. (Note that you need to save the image as jpg if you want the background to save with the image. Alternately, you can deselect the alpha channel in the VFB channels options and you will be able to save in png format without loss of quality)
Makes for very quick renders, and with the new RT (real time) rendering, setting up renders is a breeze!