Brycetech: 2D or not 2D part 2

The black and white dots above windows #1 and #2 are simply quick ways to make this particular channel of the picture texture either white or black. This has the most importance when used in the alpha channel (window #2).
For instance, if you make this window totally white (remember that white means "use this")
and use the alpha channel in diffusion (1) (or any of the channels shown in the image (2))
then the whole material will drive those attributes of the texture.
However if you had a portion of the alpha channel white and a portion of it black, only the white part of the alpha channel would drive the attribute.
For instance...diffusion...
transparency... (to achieve full transparency as shown, the "blend transparency" option in the material lab must be checked)
reflection... (to achieve full reflection as shown, the slider for transparency in the material lab must be set to 100)
The half-black/half-white dot will invert the grayscale.
Simply click it to invert the alpha channel. What was black is now white, and what was white is now black.

Ok, so why would you want to know this kind of stuff? Well, you can use it to make decorative designs by driving textures with images. Perhaps you have seen the very decorative furniture that has a mirrored surface decoration on glass. You could use this kind of material texture for a lot of decorative objects: Glasses inlayed with gold, clay pots with ancient Arabic script... anything you can imagine.
The above effect can be achieved with one object, but I used two. One cube with a glass texture and a second slightly in front of the first with an image driving the reflection.

Thus far, we have discussed "black" and "white" only, however shades of gray can be used to drive the alpha channel as well.
This can be used to apply gradient reflections... (3 spheres were placed BEHIND the camera to illustrate the reflection variations as the gradient increased.)
gradient transparency (This kind of effect could be used to add motion, distance, or whatever you want.)
or any other attribute that can be driven by the alpha channel with a grayscale image. The closer the color is to white the more it will be used and the closer it is to black the less it will be used.

Brycetech: 2D or not 2D...(pt. 2)