Although this is currently safe there is no guarantee that future refactorings will keep the current draw lists, so it's better if GLDecal used its own copy of the data.
- precalculate if a sector's floor and ceiling plane overlap. This avoids rechecking this for each single call of hw_FakeFlat.
- vertices must be marked dirty every time they change after map setup. That means that ChangePlaneTexZ must do this as well, because it cannot rely on interpolation taking care of it.
- Having a 'dirty' argument for SetPlaneTexZ's ZScript version makes no sense. If the value changes from the script side the vertices must always be marked to be recalculated.
This was all over the place, with half of it using the function and half doing incomplete checks on the underlying variables.
Also did some optimization on the IGNOREHEIGHTSEC flag: Putting it on the destination sector instead of the model sector makes the check even simpler and allows to precalculate the effect of 3D floors on the heightsec, which previously had to be run on every call and made the function too complex for inlining.
* only call hw_CheckViewArea if the result is not known yet.
* check the map up front if it even contains heightsecs. This allows to shortcut the above check entirely for maps without sector transfers and will allow further optimizations.
Lots of this was still laid out for DirectDraw. This removes most of Begin2D so that it can be done more cleanlz.
Note that this commit renders weapon sprites and screen blends incorrectly. Those will be fixed in an upcoming commit.
Since they mess around with the texture coordinates, these need to be backed up and restored afterward.
There was also an issue with the ValidNormal check that was suffering from imprecisions that cause walls to be skipped, so the check was removed because it was mostly pointless.
* split gl_shadowmap.cpp into a GL dependent and an API independent part.
* gl_drawinfo must be kept around for the HUD sprite because it connects the renderer with the hardware indpendent part of the engine.
- added thread_local to some static arrays being used for setting up dynamic lights.
Right now it's of little consequence but these will have to be maintained per thread if the render data setup is done by worker tasks.
Decals will now be processed into a list in the processing pass, allowing to use the vertex buffer even on GL3 hardware and to offload this part of the work to a multithreaded worker task.
* to do this efficiently the amount of required vertices needs to be calculated up-front
* always create the vertices in the data generation pass, not the render pass.
* added synchronisation code to the vertex buffer allocator.
Without multithreading this causes a slight slowdown, due to added processing cost. (Frozen Time bridge scene drops from 47 fps to 44 fps on my test machine.
