Also removed the + 1 from newtime, since there was never really any need for it. It just offset the interpolation so it went like (1 -> 2] instead of [1 -> 2), so you never saw the base appearance for each frame except at the end of any frames interpolating to it
Changed DrawMD2Ex's duration/tics type to INT32 so -1 comparisons work, probably want to change the signs elsewhere too but this is fine for now
OpenGL slope FOF lighting fix
This fixes some issues with sloped FOFs that affect lighting in OpenGL (as in, those that cast a shadow or have a colormap). Particularly, they can do strange things to any wall textures adjacent to them, as we've noticed ourselves in levels for 2.2. =P
See merge request !194
Polyobject seg render fix
This fixes both Software and OpenGL renderers so that polyobject segs aren't drawn if the game is drawing the actual subsectors they're from (outside the main level, where the polyobject walls were pre-spawn). They should only appear as part of the polyobject itself in-level.
This means a few glitches with polyobjects are probably fixed: for instance in Software mode, polyobject walls sometimes appear through level boundaries (and make everything above/below vanish, turning into HOM or skybox), if the BSP rendering code happens to find one of the subsectors said segs came from outside the level. I don't think anything similar happens in OpenGL, though I'm sure some unwanted typecasting is happening as a result of attempting to draw the segs. (And it fixes a crash in 2.2 anyway.)
See merge request !195
Polyobject segs should ONLY be drawn if the polyobject itself is in the polylist of a subsector being rendered. That way you won't sometimes see polyobject walls through level boundaries, if you happen to be close enough to their pre-spawn locations outside the level (or in them, if you decided to go on a noclip journey).
Some texture-related fixes
Bugs fixed in this branch:
* upper/lower/middle textures with non-existent texture ids being capable of crashing the game. For instance, RVZ1 has colormap codes on non-colormap linedefs, which causes them to wind up with invalid texture ids because of how the game tries to interpret lower/upper textures with "#" followed by characters on normal linedefs. Fortunately these "textures" are normally not visible anyway (since they're all in control sectors) unless they are swapped with in-level textures by some crazy Lua script of some sort...
* animated single-patch textures with holes displaying garbage on first viewing (see this thread: https://mb.srb2.org/showthread.php?t=42195)
* the heights of the lighting (shadows or colormapping) from water/translucent/shadowcasting/etc FOFs become messed up when displayed on repeated midtextures.
See merge request !144
I added similar checks for the other num* but it seems some MD2s break the other limits without knowing anyway ...so I've commented these checks out for now, unless we have further discussion regarding them later on
xorshift* PRNG
This needs testing to ensure I didn't mess anything up switching function names around.
Our PRNG sucks. This is probably obvious. I wish I had known better at the time I implemented it, but oh well.
The replacement is an xorshift* PRNG variant with period 2^32 - 1 (meaning that the PRNG state will loop after four billion calls ... that's not likely to happen), versus the old PRNG's period of about 2^22 (?). The output is also much more random and less predictable; the old PRNG would fall into a predictable loop of output after about 4000 numbers were generated, which isn't much.
The PRNG here also outputs numbers as fixed point from [0,1) (that's 0 to FRACUNIT-1, in other words) instead of single bytes at a time. This makes it much easier to calculate things for, say, P_RandomRange and P_RandomKey. A new macro, P_RandomChance(p), is now in use that returns true _p_ percent of the time, where _p_ is a fixed_t probability from 0 (0%) to FRACUNIT (100%).
This doesn't affect netgames at all; the code for seed saving and restoring is identical (aside from a check to prevent seed being set to 0, which breaks xorshift PRNGs). Demos break, but A: _duh_ and B: they're already broken by all the changes to physics to accommodate slopes.
P_Random is deprecated in Lua, as the function was renamed to P_RandomByte. Aside from that, nothing special.
See merge request !64
