View Full Version : Gradient input - Edge angle

09-08-2003, 11:57 PM
This is a gradient input that lets you map by the angle between polygons. This information can be found as it's needed for smoothing (ie if the angle is less than 60 then smooth) but I'm not sure how easy it'd be to make it a gradient input.

Basically you map from a 0 turn to a 180 turn (maybe use -180 to 180 to do things with the backsides of polys too?) to do things as demonstrated in the image below. The bottom image shows a simple 0 = blue 180 = red gradient. Above that the polygons have a bump map with and alpha map over the top with 0 being transparent and 180 being opaque. Using something like this you could make all of the sharper edges of your object look more worn for example.


PS this is a feature request, it deosn't really work ;)

09-11-2003, 08:17 AM
I guess no one likes this idea then .. *sigh* :p

09-11-2003, 08:21 AM
I like it. The more gradient input choices, the better.

09-11-2003, 08:26 AM
are reading in mind? ;)


09-11-2003, 08:31 AM
Hmm, but there's something I don't quite understand about what you're asking for. How does the gradient fade away from the edge? The initial value of the edge is taken from the gradient (say you specify that at 90 you have 100%). But the value at the middle of the polygon, which edge would it take its value from? There would be four edges equally close (on a square polygon surface that is). Or would it just interpolate between all the edges?

09-11-2003, 08:33 AM
I'd start a more generic "Gradient Input" Thread! ;)

There's a lot to say about gradients and a lot we can do with them (I use them everywhere)! ;)


09-11-2003, 08:53 AM
Well it'd work just like weight maps do right now, so the middle of the poly would be interpolated like a normal weight map. But (and here's the trick) if you faceted subdivide the object then you'd make the gradients return to zero in the middle of the polygon .. or the middle of the where the pre-sebdivided polygon was .. if that makes sense.

I was going to make an object to show how this would all work but it's hard to do. It could probably be done with an lscript, but it'd lose it's dynamicness.

And yeah, gradients are great, I use them all the time too :)

09-11-2003, 08:58 AM
Yup, that makes sense (the subdivided thing). I think edge angle gradient inputs would be great. Let's hope NewTek feels the same way. :cool:

09-11-2003, 10:59 AM
More gradient inputs:
-Light/Shadow ( you have this type of behavior in max with one of the blur plug)
-Real Ortho projection ( when I look thrue a distant light for example)

And give us Gradient in Viewports!

09-12-2003, 09:18 AM
More about "gradient input"...

A simple but long awaited thing regard all of the "Distance" gradients:
actually they are "0" -> "x"
but they should be "-x" -> "+x" (from negative to positive)

Bump input is "0" -> "1" but it shuold be "-1" -> "1".

More to come! ;)


09-13-2003, 02:47 AM
Great suggestion, Karmacop. This gradient type would be very useful!

My vote for it.