* dynamic lights also work in the true color software renderer and have been moved out of the OpenGL menu.
* created a separate software renderer menu and moved all relevant options there.
* delete non-applicable options when running in legacy mode.
* moved the OpenGL preferences menu one level up to eliminate a two-entry GL top level menu.
Removing this made me realize that calling the renderers' FakeFlat functions from the automap is inherently unsafe with the recent refactorings because there is absolutely no guarantee that the data may actually still be defined when the automap is being drawn.
So the best approach here is to give the automap its own FakeFlat function that runs independently of render data and assumptions of data preservation. This one can also be a lot simpler because it only needs the floor, not the ceiling info.
- 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.
- removed the LastCamera logic in RenderView. This code predates the first GZDoom release and apparently was only added because back then R_SetupFrame was not fully compatible with the hardware renderer. Today it is not needed anymore.
(Is there anyway to tone down GCC's warning level? It outputs too many false positives for potentially uninitialized variables in which the genuine errors get drowned.)
