Threshold node in Blender

Hello,

I made a threshold node which generates a black & white image based on a threshold value. Moreover the edge between the color can be softened by a smooth parameter.

I agree that a similar effect can be achieved using an RGB Curve and a Color ramp, but this is a lot of pain. I use this effect very often and it is very convenient to have such a node.

I would like to know what you think about the threshold node, in particular if you think it’s useful enough to be integrated in Blender.

Here are 2 images of the node in action.
http://blender.astrometry.net/attachment/ticket/30/threshold1.JPG
http://blender.astrometry.net/attachment/ticket/30/threshold2.JPG

Link to patch
http://projects.blender.org/tracker/?group_id=9&atid=127&func=detail&aid=7618

Personally, I don’t think it’s useful enough.

I don’t think using curves or a color ramp is a lot of pain at all - in fact it provides a more visual and intuitive way of doing it than fiddling with abstract number values. When you are doing things like glows that you need a threshold for, it’s often a lot better to have the smooth rolloff that you can get with a colorband or curves, otherwise you can have flickering during animation. It looks like the smoothness parameter on the above nodes doesn’t do that, it just makes things gray…

how do the commands on it work? smoothness is like Anti-aliasing?

Looks great IMO as long as the results can be anti aliased… could it also be selective colour thresholds rather than just value?

That’s what the matte nodes are for - isolating a specific colour (i.e. a green screen) into a mask.

I reckon it’s useful, despite the double up.
In general we need more tools that speed up workflow.
The smooth parameter doesn’t seem to work properly. It shouldn’t be lifting the blacks at all, instead it should be rolling off the transition between black and white.
P.S. I didn’t vote, cause I don’t think it’s quite there yet.

that, indeed is hard to vote on… :confused: