Why we bother reflect about x-axis? Why can not just shift the box?
fronteva
In my prospective, this maybe because (0,0)->(W,0) represents the x-axis in the normalized coordinate space and (0,0)->(0,H) represents the y-axis, so that we need to reflect about x-axis.
keenan
@maisil Because the image will be upside down! :-) Basically the viewer on the left thinks of "up" as the direction (0,1), whereas for the viewer on the right "up" is (0,-1).
Why we bother reflect about x-axis? Why can not just shift the box?
In my prospective, this maybe because (0,0)->(W,0) represents the x-axis in the normalized coordinate space and (0,0)->(0,H) represents the y-axis, so that we need to reflect about x-axis.
@maisil Because the image will be upside down! :-) Basically the viewer on the left thinks of "up" as the direction (0,1), whereas for the viewer on the right "up" is (0,-1).