Gouraud shading

Gouraud shading (goo-ROH), named after Henri Gouraud, is an interpolation method used in computer graphics to produce continuous shading of surfaces represented by polygon meshes. In practice, Gouraud shading is most often used to achieve continuous lighting on triangle meshes by computing the lighting at the corners of each triangle and linearly interpolating the resulting colours for each pixel covered by the triangle. Gouraud first published the technique in 1971. However, enhanced hardware support for superior shading models has yielded Gouraud shading largely obsolete in modern rendering.

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