Quicktip #8 Utilize the curveu attribute
Added 2018-11-26 11:04:07 +0000 UTCI have been busy preparing for the rail series so these fell a bit behind. So here is another quicktip.
As you probably know you can manipulate your geometry with attributes. But since it's not always so easy to keep an overview about the status of your attributes some people hesitate on using this approach. It's easy to get lost in the geometry spreadsheet.
But getting used to this idea will help you alot! So let me give you a smal example.
When creating a simple line and feeding it into a resample node you get a powerful attribute for free. The curveu attribute.
This creates a value from 0 to 1 on your points depending on their position. That attribute can be used for quite alot of interesting effects. But here is the most obvious one. Position displacement.
During the progression of the Railsystem this was also a function that was needed. That means I have the option to move the Point according to it's curveu value and a control on the asset. This might look like this:
This is already handy to bend grassblade or hair. But more often I find myself trying to recreate something like hanging wires. To do that you have to manipulate the curveu attribute to change it's value across the points. So instead from 0 to 1 you want to use 0-1-0 or 1-0-1. And that's what I did.
And if you combine the two options in the asset you get a combination
The math behind this - build into the asset - is a simple math trick. This allows you to reassign the curveu value on the points.
Using the attribute to manipulate the position is only one appliaction. You can also use this to distribute color or create falloff effects along the initial geometry.
Cheers
David
