The Ground Plane is an automatic display of plane where the ground would be.
uses the color and transparency of the SketchUp ground plane to create a ground plane in your rendering.
Ground Plane Materials
From the Background Tab you can define and edit materials for the Ground Plane.
This lets you apply a grass texture for land, or a Procedural Bump Map and reflection to emulate water.
- See: Background Tab
Opaque Ground Plane
Checking Opaque will ignore the transparency setting of the SketchUp ground plane and create a solid ground plane material.
Alpha Transparent Ground Plane
There is a setting on the Sun/Sky setup tab which lets you define an Alpha Transparent Ground Plane. With an Alpha Transparent Ground Plane, you can save the rendering as an Alpha Transparent image, and the ground plane will be transparent. However, shadows on the ground will be visible. This can be used to place the ground plane image on top of a background image and still see where the shadows would appear. (Of course this works best if you are placing he image on a flat surface.)
Note:If you don't have a paint program which supports transparent images, you can load images into SketchUp and the transparent alpha channel will be recognized.