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Affine Transformations









                                                                                                                   x'         a       b              c   x
                               Affine transformations are combinations of …                                        y'     =   d       e              f   y


                                      • Linear transformations, and                                                 w          0      0       1         w 
                                                                                                                         
                                                                                                                                
                                                                                                                                                           
                                                                                                                   
                                      • Translations
                               Properties of affine transformations:

                                      • Origin does not necessarily map to origin

                                      • Lines map to lines


                                      • Parallel lines remain parallel

                                      • Ratios are preserved

                                      • Closed under composition

                                      • Models change of basis





                               Will the last coordinate w always be 1?
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