In Poser you will run into odd problems with dot product because we don't have the Blender color ramp or the map range node to do things quickly and easily. Many of the blender cycles shaders you will find for dot product will have a color ramp or map range node in them. Using a math node for the separation in examples like I explained earlier will usually give an on off toggle without it, but with a color ramp or map range node you can setup a transition between multiple textures far easier. odf's example above is defaulting to zero (black) with a slight transition falloff area, and that is one way of doing it without the other nodes. But to adjust that falloff quickly becomes tedious without the other Blender nodes and a decent live preview.. I did put a ticket in for adding the map range node since it does not require any custom ui to do so. But as it stands all we have at the moment is a very well thought out Superfly freebie color ramp replacement by Richard60 and the old Firefly one. Richard60 also has a value output node that is a massive time saver in setting these shaders up, and knowing the actual values of the outputs. That freebie should be in any ones toolset that wants to play around with vector to scalar conversion math. So if you don't have that you may want to grab that. It is far better if you know what the output actually is, versus guessing what you think it should be and not getting it to work out as planned..

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