Homogeneous Coordinates
Homogeneous coordinates came into existence in 1827 when August Ferdinand Mö- bius published Der barycentrische Calcül. This is the same Möbius of Möbius strip fame. Just for fun, we’ll discuss how to render a Möbius strip later in this book. Inci- dentally, Möbius also invented the concept of barycentric coordinates, which is lever- aged by the graphics chip in your iPhone when computing the interior colors of triangles. This term stems from the word barycentre, the archaic word for center of mass. If you place three weights at the corners of a triangle, you can compute the balance point using barycentric coordinates. Their derivation is beyond the scope of this book but an interesting aside nonetheless!

— from <<iPhone 3D Programming>>

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