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Ivan_B
06-29-2010, 02:47 AM
Hi All,

Is it possible to distribute NORMAL maps with a gradient (or some other node setup) that is controlled by a weight map, much like the way you can do it it with textures..

Refer to attached image.

I use this method often when texturing a single object with multiple textures...all controlled by a single weight map with particular weight values painted on the object to represent that texture.

There is a tutorial by William on this forum
"Texturing_Using weight maps surfaces"

Is there a way to do something similar with Normal maps.

Thanks

Myagi
06-29-2010, 07:20 AM
You might get something usable if you use the Object Tangent node from DP Kit instead of the Bump Layer, and feed the color output of your gradient into the color input of that.

Ivan_B
06-29-2010, 08:26 AM
Hi Myagi,

Thanks for that!!!...seems to be working just fine.

Ivan.

Captain Obvious
06-29-2010, 08:42 AM
Oh, piece of cake. Just use a bunch of Normal Map nodes, plug the Normal output into the Color intputs for the keys, and then plug the Color output straight into the Normal input of the Surface node.

Colors (red) and Vectors (blue) are almost exactly the same in Lightwave's node editor: a triplet of floating point number.

Myagi
06-29-2010, 09:54 AM
Colors (red) and Vectors (blue) are almost exactly the same in Lightwave's node editor: a triplet of floating point number.

Isn't there a potential danger that a node might clamp negative numbers (or even >1) for colors in its internal processing, or is there some guidline somwhere that guarantees color values to stay intact no matter what value?

Captain Obvious
06-30-2010, 03:44 AM
Isn't there a potential danger that a node might clamp negative numbers (or even >1) for colors in its internal processing, or is there some guidline somwhere that guarantees color values to stay intact no matter what value?
Some nodes do clamp values or otherwise distort them. But generally, no, vectors and colors are treated the same way. The only difference I can think of, actually, is what happens when you convert them to scalars. When you convert a color to a scalar, it takes the average or the luma or something such; with vectors, it just takes the X channel. Oh, and you can't plug colors into Normal or Bump inputs. It *works*, but LW just won't let you plug it in. It's an artificial limitation. Just plug a color into a vector scale node and then plug that into bump or normal.

Ivan_B
06-30-2010, 10:16 PM
"Oh, and you can't plug colors into Normal or Bump inputs. It *works*, but LW just won't let you plug it in"

Yeah,tried that too...thats why I created this thread..

I used DPkits "Object Tangent" as suggested, and it works fine...I'll now try the "Vector scale node" see how that goes.

Thanks people!

Captain Obvious
07-01-2010, 04:21 AM
You can use ANYTHING that inputs a vector or a color and outputs a vector in order to plug "colors" into the normal or bump channels. A vector scale node takes a vector (or color) and multiplies it by the scale setting. If you leave it at 100 %, it does nothing. But because the output is a vector, you can plug it into bump or normal. So if you have a vector of 1;-1;0.5 and you plug it into a gradient's color input, it is now a color with the SAME value (255 red, -255 green, 128 blue I guess). If you plug that into a vector scale node with a scale of 100 %, it is now back to being a vector with exactly the same values as before it became a color.