- optimized the math to get a plane equation from a linedef. The original code used a generic algorithm that knew nothing about the fact that Doom walls are always perfectly vertical. With this knowledge the plane calculation can be reduced to a lot less code because retrieving the normal is trivial in this special case.
- use the SSE2 rsqrtss instruction to calculate a wall's length, because this is by far the most frequent use of square roots in the GL renderer. So far this is only active on x64, it may be activated on 32 bit later as well, but only after it has been decided if 32 bit builds should be x87 or SSE2.
# Conflicts:
# src/gl/dynlights/gl_dynlight.cpp
# Conflicts:
# src/g_shared/a_dynlightdata.cpp
Since the true color software renderer also handles them there is no point keeping them on the GL side.
This also optimized how they are stored, because we no longer need to be aware of a base engine which doesn't have them.
This was done to clean up the license and to ensure that any commercial fork of the engine has to obey the far stricter requirements concerning source distribution. The old license was compatible with GPLv2 whereas combining GPLv2 and LGPLv3 force a license upgrade to GPLv3. The license of code that originates from ZDoomGL has not been changed.
Both of these were inherited from ZDoomGL and in terms of light design in maps it makes absolutely no sense to have them user configurable. They should have been removed 11 years ago.
- restricted gl_lights_additive to legacy code and removed menu entry for this.
For modern hardware this setting is completely pointless, it offers no advantage and degrades visual quality. Its only reason for existence was that drawing additive lights with textures is a lot faster, and that's all it's being used for now.
After thinking about it for a day or so I believe it's the best option to remove all compatibility code because it's a major obstacle for a transition to a core profile.
