Controllable generation is somewhat similar to interpolation.
With interpolation, you get intermediate examples between two generated observations.
These intermediate examples between to two targets by manipulating the inputs from Z-space, which is the same idea behind controllable generation.
In order to get intermediate values between two images, for example, you can make an interpolation between their two input vectors v1 and v2 in the Z-space.
Controllable generation also uses changes in Z-space and makes use of how adjustments to the noise vector are reflected in the output from the generator.
Differences in the features generated, for example different hair colors, occur due to changes in the direction that you have to move in Z-space to modify the features of the image.
If image output of g(v1) , new controlled output with g(v1+d)