Add shadow filtering (PCF) option.
Fix ugly shadow saturation in old lighting mode.
Fix fancy water shader.
Fix camera matrix computation.
Support scissoring of camera frustum.
Optimise vertex skinning.
Inline various matrix functions.
Support filtering of the list of submitted models before a rendering
pass, for more precise culling.
Optimise water renderer (fixes#721, based on patch by ortalo).
Use scissoring when generating reflection/refraction textures.
Skip reflection/refraction texture generation when no water is visible.
Render alpha-blended objects differently (fixes#434).
Reduce shadow swimming effects.
This was SVN commit r9814.
the old debug_assert always ran and tested the expression, which slows
down release builds. wrapping them in #ifndef NDEBUG is clumsy. the new
ASSERT behaves like assert and ENSURE like the old debug_assert. Let's
change any time-critical but not-super-important ENSURE to ASSERT to
speed up release builds. (already done in bits.h and unique_range.h)
This was SVN commit r9362.
Change lighting model for new maps to allow better overbrightness.
Cache player colours instead of loading from scripts every time the
renderer wants them.
This was SVN commit r9123.
