-// Determine scenery altitude via ssg. Normally this just happens
-// when we render the scene, but we'd also like to be able to do this
-// explicitely. lat & lon are in radians. view_pos in current world
-// coordinate translated near (0,0,0) (in meters.) Returns result in
-// meters.
-bool FGTileMgr::current_elev_ssg( sgdVec3 abs_view_pos, double *terrain_elev ) {
- sgdVec3 view_pos;
- sgdVec3 sc;
- sgdSetVec3( sc, scenery.center.x(), scenery.center.y(), scenery.center.z());
- sgdSubVec3( view_pos, abs_view_pos, sc );
-
- sgdVec3 orig, dir;
- sgdCopyVec3(orig, view_pos );
- sgdCopyVec3(dir, abs_view_pos );
-
- hit_list.Intersect( terrain, orig, dir );
-
- int this_hit=0;
- Point3D geoc;
- double result = -9999;
-
- int hitcount = hit_list.num_hits();
- for ( int i = 0; i < hitcount; ++i ) {
- geoc = sgCartToPolar3d( scenery.center + hit_list.get_point(i) );
- double lat_geod, alt, sea_level_r;
- sgGeocToGeod(geoc.lat(), geoc.radius(), &lat_geod,
- &alt, &sea_level_r);
- if ( alt > result && alt < 10000 ) {
- result = alt;
- this_hit = i;
+ // insert the tile into the cache
+ if ( tile_cache.insert_tile( e ) ) {
+ // Schedule tile for loading
+ loader.add( e );
+ } else {
+ // insert failed (cache full with no available entries to
+ // delete.) Try again later
+ delete e;