I need to allow the user to create their own transfer function
y = f(x)
(I will then use this transfer function to warp the scene)
Currently I'm using a mathematical formula:
y = exp( 1/(x^2 + 1) )
But it doesn't allow a (non-mathematical) artist to shape the curve, and it is awkward even for a mathematician to turn an arbitrary shape into a mathematical formula.
Ideally I would like the user to be able to draw the curve freehand, or maybe in the same manner as constructing curves in Blender.
In fact, can I get away with using Blender's existing curve tool? Say I create a new scene, I suppose I can then create a curve that is constrained to the xy axis. But then how could I get
y = f(x) from a Python script?
And also, is there some 2D curve tool, that might allow the curve to be designed from within some panel?
Is there any solution path I'm missing?