What changed in EDuke32, build by build

Only try texcache_fetchmulti on detail texture slots.

Check that texture entries have a non-skybox filename before using it in texcache_fetchmulti.

Explicitly opt out of hicfindsubst falling back to pal 0 instead of checking against the reserved palnum range.

In gloadtile_art, (1) get the current texel's index, (2) apply alpha if index == 255, (3) get the index by indexing into the specified palookup table, and then (4) apply fullbright considerations. Previously these tasks were performed in order 1432.

Add a new pthtyp flag to mark textures that should not be processed by the fixtransparency() hack (which avoids the transparent color blending into a sprite when texture filtering is enabled), such as non-(T)ROR-masking floors and ceilings, white- and mask-walls, paper-skies, and rotatesprite with orientation flag 64. This commit makes sure the flag's status always fits the situation.

Don't test (!usemodels || md_tilehasmodel(picnum, pal) < 0) in eligible_for_tileshades (called only from getshadefactor) because getshadefactor is only called when a model is *not* being drawn, and therefore results in incorrect shading when drawing a tile with a model defined and models enabled to the screen or as a skybox.

Slight optimizations in getshadefactor.

bump the allowed range for 'r_pr_hudangadd' to [-1024 .. 1024].

properly calc start/end fog dist for r_usenewshading=2, vis=0, shade>0

make flipping closer to classic.