I did initially try to tackle this problem by constructing procedural solid models, but that solution wasn't sufficiently general. I ultimately went with blend

I did initially try to tackle this problem by constructing procedural solid models, but that solution wasn't sufficiently general. I ultimately went with blender's displacement modifier, which works by using a UV mapped bitmap image that displaces the model's vertices as a function of the pixel intensity. This workflow adapts well to arbitrary geometry and customer images.