How to Prepare Bump Maps in Photoshop
For best results, use a map with a considerable amount of shading to simulate texture: Once you’ve created the bump map, all you need to do is import it into your 3D animation program. Different 3D graphics programs have different ways of integrating bump maps into a model or polygon surface. The controls for the bump map should allow you to define a range to make sure the raised textures and depressions don’t extrude to extremes or scale down so small that they hardly show.
What Are Bump Maps?
Bump maps are used in 3D modeling to artificially create textured surfaces without having to model the individual details. All 3D bump maps start out as 2D drawings, so before you open your modeling software, you should prepare the bump map image in Photoshop. Bump maps are layered under full-color painted texture maps and use grayscale to instruct 3D modeling programs on how far to extrude polygonal surfaces. Black represents the highest extreme of extrusion, white represents the flattest areas, and shades of gray cover everything in between. Rather than you having to manually choose every little bump on your model, a bump map automates the process. It tells the 3D program to change the polygons in relation to your bump map procedurally, which reduces the load on computer resources when it renders the model. For example, if you were texturing a lizard’s skin, a bump map for the skin could use a mid-level gray as a baseline for the skin surface, with white for the deepest cracks and darker gray spots for the raised areas. You can even use a bump map to make facial highlights and shadows seem more realistic or add details such as folds and wrinkles to a model’s clothing.
