What changed in EDuke32, build by build

This also fixes a warning when building for Windows.

Getting the texture handles without requiring invalidation means we can handle ART-animating tilenums without impacting performance too much.

Polymer has a hack that snaps horiz values of spotlights between 90 and 110 to 90 and 110 to avoid triggering aliasing artifacts with perfectly horizontal spotlights. Propagate that change all the way to the spotlight SE sprite so that the code won't think that the horiz is always different from the light and mark it invalid each frame.

This won't actually do anything until the a debug bit is added when creating the context, but that requires support for GLX_create_context which SDL doesn't support. I'll add support for WGL_create_context to winlayer in a bit as a stopgap. Also updates our local copy of glext.h with a fresh one from the Khronos registry.

We need to Y-invert the projection texcoords when sampling from the lightmap.

Sprites would stick with their old material on global palette change. This goes through all prsprites and clobbers their CRCs so that an alternate skin / tint / highpal can be applied accordingly.

The winding order of faces is different if only flipping about X or Y, and we were unconditionally culling CW faces.

Keep track of which side is getting culled, swap around mirrors, swap around model drawing.

In cases where performing occlusion queries for multiple red walls leading to the same sector, we would sometimes leak a number of query objects. This was apparently harmless on NVIDIA drivers, but would leak tons of memory on ATI.

The code was using the Polymer-cached version of the sector cstat to determine the translucency of its diffuse material, meaning it would never get it right on the first try; that's what you get for having completely different variables named 's' and 'sec'.

We normally enable backface culling always, but turn it off for two-sided sprites; we need to make sure it's re-enabled after that as sector masks are drawn after.

Some of the ROR code was operating under the assumption that drawasks always correspond to one call of polymer_displarooms(), but that's not necessarily the case; external view draws all sectors from the top polymer_drawrooms(), which was causing crashes. Just ignore the sector mask queues in external view mode, we already don't draw masked walls.

Check all the bunch siblings if we get a floor/ceiling hit and walk them if their own planes hit.

When walking the sectors in displayrooms, detect floor/sector masks to place them in a mask queue. The queues are allocated on the heap, but a stack pointer is maintained by the displayrooms to allow it to play nice with mirror recursion. Right now the masks are drawn after all of drawmasks is finished; that means you can see sprites and wall masks through sector masks, but not the opposite. There is a slight attempt at blending far to near, but nothing too conclusive yet; that means that in some cases some sector masks won't be visible through other sector masks, but it should work for trivial cases. The next step would be to copy all the drawmasks logic into Polymer and have it (attempt to) properly interleave sector masks where they belong in the blending order.

Previously they would get counted both as 1-way walls for immediate drawing and as mask walls for delayed drawing.

Doesn't actually matter that much.