...and then, once you figure out all the not simple details of drawing and physics, you have to try and shoe horn/squeeze/cram/stuff that into x-planes incredibly limited possibilities for actually letting you SEE the texture and effects, which usually has an awesome side effect like ruining the alpha channels of something like clouds, glass, or buildings or whatever... plenty of historical bugs out there on this. We're not ignorant of these effects and things like spherical reflection mapping. We don't do "it" because we're fully aware of all the horrible compromises that have to be made.