3D printing is a technique to create digital objects in real life. This technology is mostly focused on reproducing the digital geometry itself – colored patterns (textures) still remains a challenge, and we only have very rudimentary technology to do that.
Hydrographic printing on 3D surfaces is a really simple technique: you place a film in water, use a chemical activator spray on it, and shove the object in the water.
However, since these objects start stretching the film, the technique is not very accurate, and it only helps you putting repetitive patterns on these objects.
Computational Hydrographic Printing is a technique that simulates all of these physical forces that are exerted on the film when your desired object is immersed into the water. Then, it creates a new image map taking all of these distortions into account, and this image you can print with your home inkjet printer. The results will be really accurate, close to indistinguishable from the digitally designed object.