Let's make a simple black glassy material. I won't deal with gamma correction yet, so if you don't have Poser Pro with render GC, you'll get very different results. We'll fix that in a bit.   So we want the true Fresnel calculation for IOR = 1.5.

This is easy. In matmatic, you say:

fresnel = TrueFresnel(1.5)

The fresnel variable is now a bunch of nodes that calculate the correct reflection coefficient for a 100% smooth material with an IOR of 1.5.

Now we need a reflect node. This is also easy:

reflect = Reflect()

Now we need to combine the fresnel effect with the reflect node. We could do this using the poser surface Reflection_Color and Reflection_Value channels. But this is a lot of typing, and also when we deal with shader GC, we can't use those anyway.

All we want is to use the fresnel coefficient as a coefficient - a multiplier. So we make our combination by simplying multiplying the two values.

combination = fresnel * reflect

And we want to make this our material output. Since this is so very common, matmatic has a very simply function, View, that takes one argument - what you want to see as the output of the shader. It builds an otherwise empty surface, and connects the argument to the Alternate_Diffuse channel.

surface = View(combination)

So let's put that all together - here is the entire script:

fresnel = TrueFresnel(1.5)
reflect = Reflect()
combination = fresnel * reflect
surface = View(combination)

For those that are amused by brevity, this can also be written as the one-liner:

View(TrueFresnel(1.5) * Reflect())

However, in steps that follow, we'd need to take that apart, so I'd stick with the four-line version.

The attached render shows the result.

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