Gouraud Shading

When Microsoft® Direct3D® renders a polygon using Gouraud shading, it computes intensities for each vertex by using the vertex normal and lighting parameters. Then, it linearly interpolates intensities across the face of the polygons. For example, if the red component of the color of vertex 1 is 0.8 and the red component of vertex 2 is 0.4, using the Gouraud shading mode and the RGB color model, the Direct3D rasterization module assigns a red component of 0.6 to the pixel at the midpoint of the line between these vertices.

The following figure demonstrates Gouraud shading. This teapot is composed of many triangular polygons. However, Gouraud shading makes the surface of the object appear curved and smooth.

Gouraud shading can also be used to display objects with sharp edges. For more information, see Face and Vertex Normal Vectors.

 Last updated on Thursday, April 08, 2004

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