Graphics Reference
In-Depth Information
Figure 2-76
Mask transparency selected in the Transparency panel of Material properties
The middle knight uses Z transparency, with the settings shown in
Figure 2-77
. Z transparency takes two
values into consideration: the material'salpha value andthe Zvalues ofthe points inthe scene. The alpha value
of a material is a measure of how opaque the material is. A 0 (zero) alpha means the material is completely
invisible; a 1 alpha means that the material is entirely opaque. The Z value is the distance of a point in space
alongthecamera'slocalz-axis;thatis,thedistancefromthecamera.Ztransparencyworksverymuchlikelayer
transparency in a 2D image-manipulation program, using the Z value to determine the ordering of the layers. In
the image, the middle knight's alpha value is set to 0.2.
Figure 2-77
Z transparency values
The knight on the right also has an alpha value of 0.2, but with Raytrace transparency and the values shown
in
Figure 2-78
. As you can see, the effect is very different from that of the middle knight. Whereas the middle
knight looks ghostly, the third knight looks like it is made of a real-world transparent material.
Figure 2-78
Raytrace transparency values
