- 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
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.