Thanks so much! That’s awesome! Now I can see the gradient with your code!
camera.minZ = 1;
camera.maxZ = 17;
In case other readers encounter the same thing, FYI:
The camera minZ, maxZ: Camera | Babylon.js Documentation (babylonjs.com)
They define the near and far clipping plane of the camera.
By default (the doc doesn’t say it, but I test it in the playground), minZ is 1, maxZ is 10000.
The depth buffer will map that to a r value of 0 to 1 (the g b a values are just 1).