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Shuffled around and restructured the terrain elevation interesection code

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to make it usable by the threaded tile loader for placing objects at ground
level at load time.
This commit is contained in:
curt 2001-07-11 15:51:21 +00:00
parent bc4859c0fb
commit 4b23576df1
4 changed files with 100 additions and 80 deletions
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83
src/Scenery/hitlist.cxx
View file

@ -14,11 +14,19 @@
#include <simgear/constants.h>
#include <simgear/sg_inlines.h>
#include <simgear/debug/logstream.hxx>
#include <simgear/math/point3d.hxx>
#include <simgear/math/sg_geodesy.hxx>
#include <simgear/math/vector.hxx>
#include <Main/globals.hxx>
#include "hitlist.hxx"
extern ssgBranch *terrain;
// check to see if the intersection point is
// actually inside this face
static bool sgdPointInTriangle( sgdVec3 point, sgdVec3 tri[3] )
@ -304,3 +312,78 @@ void FGHitList::IntersectCachedLeaf( sgdMat4 m,
}
}
}
static void CurrentNormalInLocalPlane(sgVec3 dst, sgVec3 src) {
sgVec3 tmp;
sgSetVec3(tmp, src[0], src[1], src[2] );
sgMat4 TMP;
sgTransposeNegateMat4 ( TMP, globals->get_current_view()->get_UP() ) ;
sgXformVec3(tmp, tmp, TMP);
sgSetVec3(dst, tmp[2], tmp[1], tmp[0] );
}
// a temporary hack until we get everything rewritten with sgdVec3
static inline Point3D operator + (const Point3D& a, const sgdVec3 b)
{
return Point3D(a.x()+b[0], a.y()+b[1], a.z()+b[2]);
}
// 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 fgCurrentElev( sgdVec3 abs_view_pos, sgdVec3 scenery_center,
FGHitList *hit_list,
double *terrain_elev, double *radius, double *normal)
{
sgdVec3 view_pos;
sgdSubVec3( view_pos, abs_view_pos, scenery_center );
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;
Point3D sc(scenery_center[0], scenery_center[1], scenery_center[2]) ;
int hitcount = hit_list->num_hits();
for ( int i = 0; i < hitcount; ++i ) {
geoc = sgCartToPolar3d( sc + 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;
}
}
if ( result > -9000 ) {
*terrain_elev = result;
*radius = geoc.radius();
sgVec3 tmp;
sgSetVec3(tmp, hit_list->get_normal(this_hit));
// cout << "cur_normal: " << tmp[0] << " " << tmp[1] << " "
// << tmp[2] << endl;
/* ssgState *IntersectedLeafState =
((ssgLeaf*)hit_list->get_entity(this_hit))->getState(); */
CurrentNormalInLocalPlane(tmp, tmp);
sgdSetVec3( normal, tmp );
// cout << "NED: " << tmp[0] << " " << tmp[1] << " " << tmp[2] << endl;
return true;
} else {
SG_LOG( SG_TERRAIN, SG_INFO, "no terrain intersection" );
*terrain_elev = 0.0;
float *up = globals->get_current_view()->get_world_up();
sgdSetVec3(normal, up[0], up[1], up[2]);
return false;
}
}

9
src/Scenery/hitlist.hxx
View file

@ -93,4 +93,13 @@ inline void FGHitList::Intersect( ssgBranch *scene,
}
}
// Associated function, assuming a wgs84 world with 0,0,0 at the
// center, find the current terrain intersection elevation for the
// point specified.
bool fgCurrentElev( sgdVec3 abs_view_pos, sgdVec3 scenery_center,
FGHitList *hit_list,
double *terrain_elev, double *radius, double *normal );
#endif // _HITLIST_HXX

83
src/Scenery/tilemgr.cxx
View file

@ -63,12 +63,6 @@ extern ssgBranch *ground;
FGTileMgr global_tile_mgr;
// a temporary hack until we get everything rewritten with sgdVec3
static inline Point3D operator + (const Point3D& a, const sgdVec3 b)
{
return Point3D(a.x()+b[0], a.y()+b[1], a.z()+b[2]);
}
#ifdef ENABLE_THREADS
SGLockedQueue<FGTileEntry *> FGTileMgr::attach_queue;
SGLockedQueue<FGDeferredModel *> FGTileMgr::model_queue;
@ -153,72 +147,6 @@ void FGTileMgr::sched_tile( const SGBucket& b ) {
}
static void CurrentNormalInLocalPlane(sgVec3 dst, sgVec3 src) {
sgVec3 tmp;
sgSetVec3(tmp, src[0], src[1], src[2] );
sgMat4 TMP;
sgTransposeNegateMat4 ( TMP, globals->get_current_view()->get_UP() ) ;
sgXformVec3(tmp, tmp, TMP);
sgSetVec3(dst, tmp[2], tmp[1], tmp[0] );
}
// 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;
}
}
if ( result > -9000 ) {
*terrain_elev = result;
scenery.cur_radius = geoc.radius();
sgVec3 tmp;
sgSetVec3(tmp, hit_list.get_normal(this_hit));
// cout << "cur_normal: " << tmp[0] << " " << tmp[1] << " "
// << tmp[2] << endl;
/* ssgState *IntersectedLeafState =
((ssgLeaf*)hit_list.get_entity(this_hit))->getState(); */
CurrentNormalInLocalPlane(tmp, tmp);
sgdSetVec3( scenery.cur_normal, tmp );
// cout << "NED: " << tmp[0] << " " << tmp[1] << " " << tmp[2] << endl;
return true;
} else {
SG_LOG( SG_TERRAIN, SG_INFO, "no terrain intersection" );
*terrain_elev = 0.0;
float *up = globals->get_current_view()->get_world_up();
sgdSetVec3(scenery.cur_normal, up[0], up[1], up[2]);
return false;
}
}
// schedule a needed buckets for loading
void FGTileMgr::schedule_needed() {
#ifndef FG_OLD_WEATHER
@ -401,6 +329,8 @@ int FGTileMgr::update( double lon, double lat ) {
}
}
counter_hack = (counter_hack + 1) % 5;
sgdVec3 sc;
sgdSetVec3( sc, scenery.center[0], scenery.center[1], scenery.center[2] );
if ( scenery.center == Point3D(0.0) ) {
// initializing
@ -419,7 +349,9 @@ int FGTileMgr::update( double lon, double lat ) {
prep_ssg_nodes();
sgSetVec3( tmp_view_pos, 0.0, 0.0, 0.0 );
double tmp_elev;
if ( current_elev_ssg(tmp_abs_view_pos, &tmp_elev) ) {
if ( fgCurrentElev(tmp_abs_view_pos, sc, &hit_list,
&tmp_elev, &scenery.cur_radius, scenery.cur_normal) )
{
scenery.cur_elev = tmp_elev;
} else {
scenery.cur_elev = 0.0;
@ -429,8 +361,9 @@ int FGTileMgr::update( double lon, double lat ) {
// cout << "abs view pos = " << current_view.abs_view_pos
// << " view pos = " << current_view.view_pos << endl;
double tmp_elev;
if ( current_elev_ssg(globals->get_current_view()->get_abs_view_pos(),
&tmp_elev) )
if ( fgCurrentElev(globals->get_current_view()->get_abs_view_pos(),
sc, &hit_list,
&tmp_elev, &scenery.cur_radius, scenery.cur_normal) )
{
scenery.cur_elev = tmp_elev;
} else {

5
src/Scenery/tilemgr.hxx
View file

@ -81,10 +81,6 @@ private:
// see comment at prep_ssg_nodes()
void prep_ssg_node( int idx );
// int hitcount;
// sgdVec3 hit_pts [ MAX_HITS ] ;
// ssgEntity *last_hit;
FGHitList hit_list;
SGBucket previous_bucket;
@ -177,7 +173,6 @@ public:
const sgdVec3 p, const sgdVec3 dir,
FGHitList *list );
bool current_elev_ssg( sgdVec3 abs_view_pos, double *terrain_elev );
// Prepare the ssg nodes ... for each tile, set it's proper
// transform and update it's range selector based on current