8.5.10 TexturingThe texture unit can cover any primitive with a picture. The picture can bestretched, shared, rotated and translated with the texture unit in one step. Toavoid aliasing the result can be filtered bilinear in u and v directions.8.5.10.1 Mathematical backgroundThe arbitrary mapping problem is completely determined by a mapping from 3points in object space (x,y) to 3 points in texture space (u,v).Let there be the following mapping:==⇒===⇒===⇒=hvupyxpwvupyxpvupyxp0~0~00~222222111111000000While w is the width of the texture and h is the height of the texture.Examine the following picture in object space. To simplify calculations thedifference vectors are taken for calculations:022011ppdppd−=−=This is equivalent to transforming from coordinate system O to coordinate systemO’.Drawing Engine Chapter 8Preliminary User's Manual S19203EE1V3UM00 241
