Can anyone help explain the P node a little better? How it works, maybe an example of it in use. This may be a repost - sorry if is.

It outputs the position, as a vector, of the point in space where the material is being evaluated. You use where you want the material output to depend on the objects place in the scene, as with the "Global Coordinates" option in some of the 3D Textures.

Thank you, that's what i thought but I can't get the effect I'm looking for. I want a snapshot of a figure appearing to fade from the bottom up. I tried pluging a P node (x=0,y=1,z=0) into a color ramp (white to black) and pluged that into the tranceparancy (set to 1)? However this fades too quickly and only the feet fade. Changing the y to a higher value only makes the fading transistion sharper not higher up on the figure. How do raise the overall fading height?

bookmark. the complexity and power of the material room captivates me. ::::: Opera :::::

Remember that the material is only going to apply as far along the figure as that material zone applies -- and is only going to apply to the material zone.

There are two things you will need to do to the Y value 1) Add an offset 2) Multiply by a scale factor.

To determine the values to use you need to know the minimum and maximum Y coordinates of the figure, call these Ymin and Ymax.
As you want the transparency to go from 0 to 1, the values for the offset and scale factor are then as follows :-
Scale factor = (Ymax - Ymin)
Offset = -Ymin

Don't forget to set the Edge and Falloff to 0

Ahh,yes. That's exactly what I was looking for. Thank you very much, nruddock, for the mini-tutorial.

For working out what height settings you want to use for height dependent materials, here's a handy measuring material.

This is essentially the same as nruddock's shader in post 6, but if you are using the measuring shader to work out where you want things to happen then you might find this one more intuitive to set. Use math functions 3 to set the height where you want transition to begin and use math functions 5 to set how many height units you want the transition to last for.

Here's a more interesting version of the measuring shader. This one has half of the ruler showing ten unit intervals. This will work on any of the plane props that come with Poser. It relies on UV coords to make the split between the two measurement scales, so you need a correctly UV mapped object to use as a ruler. Note that all of these measuring materials are scale independent so you can scale your measuring prop as much as you like and the units will still be accurate.

fantastic!

One more. This is a similar idea to the last one except you don't need to worry about UV mapping for this one. Each stripe is one unit. The colours change every ten units.

Thank you, too Ajax. It amazing what you can do with the material's room. :)