Topological mapping (in English, bump mapping) is a technique of 3D computer graphics created by James F. Blinn in 1978. It consists of giving a rough appearance to the surfaces of objects. This technique modifies the normals of the surface without changing its geometry. The original normals of the surface will remain perpendicular to it. The topological mapping changes the perpendicularity by other normals to achieve the desired effect, all without modifying the topology or the geometry of the object. The result is reasonably rich and detailed, and great resemblance to natural elements (such as the texture of an orange) can be achieved. The difference between displacement mapping and topological mapping is that the latter does not disturb the geometry, only the direction of the normal field.
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