Can I define a coordinate system based on a mesh, as generated coordinates are based on a bounding box? I am making a procedural cloud based on CGMatter's which takes the shape of the mesh assigned the cloud material, with the added ability to 'shrink' the initial (pre-distortion) volume box so the cloud does not have hard edges where the mesh stops. My problem is that since I am using generated volume coordinates, the shrunk volume takes the shape of a smaller version of the cloud meshes bounding box, instead of the mesh. I want to define a coordinate system that is 1 or -1 at the edges of the mesh, or a similarly effective approach.
Here is a pic of the cloud and mesh in ortho view:
I think you might be wanting this setup, where we use Vector Math nodes to convert Generated Coordinates to something equal or almost equal to Object Space.
It's commonly used with Vector Displacement, because Generated space performs some very specific transformations better than Object.