1. Only one copy of each object (and its texture) is stored in memory,
no matter how many materials use it.
2. Random objects are added to a triangle only when the objects are in
range, and they are deleted as soon as the objects are out of
range. That way, only a relatively small number of ssg nodes are
used at any one time.
This patch seems to eliminate freezes when tiles are freed. There are
occasional stutters at extremely high speeds (i.e. over 3,000kt), but
it seems smooth enough for normal aviation speeds.
The first hunk might not be necessary, but the light_coverage property
was the only one that wasn't explicitly defaulted, which is unfair. ;-)
The second hunk adds the missing initialization to the init routine.
This is necessary, because (unlike the material entries from material.xml)
the generated light entries don't get the light coverage set. Yet
obj.cxx:795 reads this information out fot every leaf, although not needed
in the case of lights. Avoiding this isn't worth the trouble.
The last hunk sets the missing normal_index. The POINTS branch in
gen_leaf was always called with this int_list empty, which made the normals
handling use data garbage.
/sim/freeze/master (implimented)
/sim/freeze/fuel (implimented)
/sim/freeze/position (not implimented)
/sim/freeze/time-of-day (not implimented)
/sim/freeze/master is bound to the 'p' key via keyboard.xml, however,
/sim/freeze/fuel is not bound to anything at the moment so you must
change it via the external property interface, or specify an initial
value on the command line.
material-specific logic is now removed from the material library and
encapsulated in the material class itself, and materials are loaded
from $FG_ROOT/materials.xml rather than $FG_ROOT/materials. This also
removes a nasty bug in the old material-loading code that caused a
floating-point exception.
have multiple ptrs to individual entries (aliases) but the destructor was
trying to delete every ptr so it would delete already freed memory for aliases.
I implimented a simple ref counting scheme (similar to the plib mechanism) to
track references to material lib entries and only "delete" them when the last
reference is removed.
He writes:
Here are the final changes to add threads to the tile loading. All the
thread related code is in the new FGTileLoader class.
./configure.in
./acconfig.h
Added --with-threads option and corresponding ENABLE_THREADS
definition. The default is no threads.
./src/Scenery/tilemgr
Removed load_queue and associated references. This has been replaced by
a new class FGTileLoader in FGNewCache.
Made the global variable global_tile_cache a member.
schedule_needed(): removed global_tile_cache.exists() tests since
sched_tile() effectively repeats the test.
initialize_queue(): removed code that loads tiles since this is now
performed by FGTileLoader.
update(): ditto
./src/Scenery/newcache
Added new class FGTileLoader to manage tile queuing and loading.
tile_map typedefs are private.
exists() is a const member function.
fill_in(): deleted
load_tile(): added.
./src/Scenery/FGTileLoader
The new threaded tile loader. Maintains a queue of tiles waiting to be
loaded and an array of one or more threads to load the tiles. Currently
only a single thread is created. The queue is guarded by a mutex to
synchronize access. A condition variable signals the thread when the
queue is non-empty.
CLO: I made a few tweaks to address a couple issues, hopefully what we
have is solid, but now we kick it out to the general public to see. :-)
