Normal mapping is a sort of improved bump mapping. It simulates structures on a flat geometry. It looks good when you look at it with a 90° angle but the illusion disappears if you look at it almost parallel to the surface. Then you will notice, that the structure is flat. The advantage of it is, it does not need much processing power of a computer. FF14 uses normal mapping everywhere. But the normal maps have to fit exactly to a geometry. If they don't then the lighting and self shadowing will look very weird in some situations.
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