Description: The surface normal is a vector that is perpendicular to the surface of a shape in three-dimensional space. This concept is fundamental in computer graphics, especially in the representation and manipulation of 3D objects. Surface normals are crucial for determining how light interacts with a surface, which directly affects the lighting and shading in a scene. Mathematically, a normal is defined as a vector that can be calculated from the tangent vectors to the surface at a given point. The direction of the normal influences how an object is rendered, as it determines how light rays are reflected and refracted. Additionally, normals are essential for collision calculations and for simulating physics in 3D environments. Normals are used in various graphics APIs to calculate the lighting of the polygons that make up a 3D model, thus allowing for a more realistic representation of objects in a scene. The correct definition and use of surface normals are vital for achieving convincing visual effects and precise interaction between objects in a virtual environment.
