// o optimize the update[sector|wall] functions to diff the changes
// o make occlusion queries every n frames (cvar)
// o there's still a texture alignment problem with slopes (waterfall in launch facility)
// o there's also the texture alignment problem Hunter reported (san andreas fault)
// o port glowmaps and detail maps from hacked polymost (:(
// o shading needs a lot of work
// o make the portal smaller
// o one-way walls and masks
// o remove all the IM matrix crap and write real functions now that it works
// o polymer.c possibly needs to be split in several source files
// o some crap really needs factorization
// o ... possibly more important stuff I don't have in mind right now
// - SPRITES
// o stop using IM
// o stop using Get for every face sprite (do the calculation by hand)
// o port sprite panning and fullbrights from hacked polymost (:(
// o draw all opaques first, keep translucent for later with masks
// o need smart PolygonOffset for floor and wall sprites
// - SKIES
// o figure a better way to handle ART skies - maybe add symetric caps that would fade to black like a big gem or something wow this is a long column lol ;0)
// o implement polymost skyboxes
// - MIRRORS
// o figure out how to get mirror data from game
// o unified mirror transformation (not just walls)
// - MDSPRITES
// o need to reimplement them - hopefully the loader can be reused without too much hassle
// o need full translation and rotation support from CON to attach to game world or tags
// o need to put frames into VBOs and blend between them
//
// the renderer should hopefully be pretty solid after all that
