In SpeedTree 8 our materials have changed to Physical Based Rendering (PBR). The Modeler is reflecting realistic shading and lighting along with measured surface values to represent real-world materials. Our assets now include these maps:
Otherwise known as the color map. This defines the color of the diffused light.
This map is the cut out of your material. The black value marks the negative, everything taken away. (Hint: You can get some convincingly aged leaves by a opacity map with a few holes in the inside.)
The normal map is used to provide physical detail to the surface by perturbing the facing direction, of each individual pixel. Contrasting the normal will allow you to control how much of the surfaces edges are exaggerated.
This map controls how “metal-like” your surface will be. Nonmetals have Metallic values of 0, metals have Metallic values of 1. For pure surfaces, such as pure metal, pure stone, pure plastic, etc. this value will be 0 or 1, not anything in between. When creating hybrid surfaces like corroded, dusty, or rusty metals, you may find that you need some value between 0 and 1.
The Subsurface Color simulates shifts in color when light passes through the surface. On your leaves this will show with the light source shining directly through them.
This controls the amount of light coming through the material. Your values will be from 0 to 1. A very thin delicate petal for example would let most of the light pass through it and would be set at .9 . A thick leaf like a magnolia might be set at something like .2 as very little light come's through them.
Ambient occlusion (AO)
This is used to help simulate the self-shadowing that happens within crevices of a surface.
* Custom space
We wanted the user to have a full range of experiemental options so we've included a custom space to add in extra maps.
If you're looking for how to load and use assets, take a look at our Material Asset page