Initial revision.
This commit is contained in:
parent
cd1a471f7e
commit
bb61414e04
2 changed files with 424 additions and 0 deletions
src/Scenery
328
src/Scenery/hitlist.cxx
Normal file
328
src/Scenery/hitlist.cxx
Normal file
|
@ -0,0 +1,328 @@
|
||||||
|
#ifdef HAVE_CONFIG_H
|
||||||
|
# include <config.h>
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#ifdef HAVE_WINDOWS_H
|
||||||
|
# include <windows.h>
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include <math.h>
|
||||||
|
|
||||||
|
#include <GL/glut.h>
|
||||||
|
|
||||||
|
#include <simgear/constants.h>
|
||||||
|
#include <simgear/math/vector.hxx>
|
||||||
|
#include <simgear/xgl/xgl.h>
|
||||||
|
|
||||||
|
#include "hitlist.hxx"
|
||||||
|
|
||||||
|
template <class T>
|
||||||
|
inline const int FG_SIGN(const T x) {
|
||||||
|
return x < T(0) ? -1 : 1;
|
||||||
|
}
|
||||||
|
|
||||||
|
template <class T>
|
||||||
|
inline const T FG_MIN(const T a, const T b) {
|
||||||
|
return a < b ? a : b;
|
||||||
|
}
|
||||||
|
|
||||||
|
// return the minimum of three values
|
||||||
|
template <class T>
|
||||||
|
inline const T FG_MIN3( const T a, const T b, const T c)
|
||||||
|
{
|
||||||
|
return (a < b ? FG_MIN (a, c) : FG_MIN (b, c));
|
||||||
|
}
|
||||||
|
|
||||||
|
template <class T>
|
||||||
|
inline const T FG_MAX(const T a, const T b) {
|
||||||
|
return a > b ? a : b;
|
||||||
|
}
|
||||||
|
|
||||||
|
// return the maximum of three values
|
||||||
|
template <class T>
|
||||||
|
inline const T FG_MAX3 (const T a, const T b, const T c)
|
||||||
|
{
|
||||||
|
return (a > b ? FG_MAX (a, c) : FG_MAX (b, c));
|
||||||
|
}
|
||||||
|
|
||||||
|
// check to see if the intersection point is
|
||||||
|
// actually inside this face
|
||||||
|
static bool sgdPointInTriangle( sgdVec3 point, sgdVec3 tri[3] )
|
||||||
|
{
|
||||||
|
double xmin, xmax, ymin, ymax, zmin, zmax;
|
||||||
|
|
||||||
|
// punt if outside bouding cube
|
||||||
|
if ( point[0] < (xmin = FG_MIN3 (tri[0][0], tri[1][0], tri[2][0])) ) {
|
||||||
|
return false;
|
||||||
|
} else if ( point[0] > (xmax = FG_MAX3 (tri[0][0], tri[1][0], tri[2][0])) ) {
|
||||||
|
return false;
|
||||||
|
} else if ( point[1] < (ymin = FG_MIN3 (tri[0][1], tri[1][1], tri[2][1])) ) {
|
||||||
|
return false;
|
||||||
|
} else if ( point[1] > (ymax = FG_MAX3 (tri[0][1], tri[1][1], tri[2][1])) ) {
|
||||||
|
return false;
|
||||||
|
} else if ( point[2] < (zmin = FG_MIN3 (tri[0][2], tri[1][2], tri[2][2])) ) {
|
||||||
|
return false;
|
||||||
|
} else if ( point[2] > (zmax = FG_MAX3 (tri[0][2], tri[1][2], tri[2][2])) ) {
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
|
||||||
|
// (finally) check to see if the intersection point is
|
||||||
|
// actually inside this face
|
||||||
|
|
||||||
|
//first, drop the smallest dimension so we only have to work
|
||||||
|
//in 2d.
|
||||||
|
double dx = xmax - xmin;
|
||||||
|
double dy = ymax - ymin;
|
||||||
|
double dz = zmax - zmin;
|
||||||
|
double min_dim = FG_MIN3 (dx, dy, dz);
|
||||||
|
|
||||||
|
//first, drop the smallest dimension so we only have to work
|
||||||
|
//in 2d.
|
||||||
|
double x1, y1, x2, y2, x3, y3, rx, ry;
|
||||||
|
if ( fabs(min_dim-dx) <= FG_EPSILON ) {
|
||||||
|
// x is the smallest dimension
|
||||||
|
x1 = point[1];
|
||||||
|
y1 = point[2];
|
||||||
|
x2 = tri[0][1];
|
||||||
|
y2 = tri[0][2];
|
||||||
|
x3 = tri[1][1];
|
||||||
|
y3 = tri[1][2];
|
||||||
|
rx = tri[2][1];
|
||||||
|
ry = tri[2][2];
|
||||||
|
} else if ( fabs(min_dim-dy) <= FG_EPSILON ) {
|
||||||
|
// y is the smallest dimension
|
||||||
|
x1 = point[0];
|
||||||
|
y1 = point[2];
|
||||||
|
x2 = tri[0][0];
|
||||||
|
y2 = tri[0][2];
|
||||||
|
x3 = tri[1][0];
|
||||||
|
y3 = tri[1][2];
|
||||||
|
rx = tri[2][0];
|
||||||
|
ry = tri[2][2];
|
||||||
|
} else if ( fabs(min_dim-dz) <= FG_EPSILON ) {
|
||||||
|
// z is the smallest dimension
|
||||||
|
x1 = point[0];
|
||||||
|
y1 = point[1];
|
||||||
|
x2 = tri[0][0];
|
||||||
|
y2 = tri[0][1];
|
||||||
|
x3 = tri[1][0];
|
||||||
|
y3 = tri[1][1];
|
||||||
|
rx = tri[2][0];
|
||||||
|
ry = tri[2][1];
|
||||||
|
} else {
|
||||||
|
// all dimensions are really small so lets call it close
|
||||||
|
// enough and return a successful match
|
||||||
|
return true;
|
||||||
|
}
|
||||||
|
|
||||||
|
// check if intersection point is on the same side of p1 <-> p2 as p3
|
||||||
|
double tmp = (y2 - y3) / (x2 - x3);
|
||||||
|
int side1 = FG_SIGN (tmp * (rx - x3) + y3 - ry);
|
||||||
|
int side2 = FG_SIGN (tmp * (x1 - x3) + y3 - y1);
|
||||||
|
if ( side1 != side2 ) {
|
||||||
|
// printf("failed side 1 check\n");
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
|
||||||
|
// check if intersection point is on correct side of p2 <-> p3 as p1
|
||||||
|
tmp = (y3 - ry) / (x3 - rx);
|
||||||
|
side1 = FG_SIGN (tmp * (x2 - rx) + ry - y2);
|
||||||
|
side2 = FG_SIGN (tmp * (x1 - rx) + ry - y1);
|
||||||
|
if ( side1 != side2 ) {
|
||||||
|
// printf("failed side 2 check\n");
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
|
||||||
|
// check if intersection point is on correct side of p1 <-> p3 as p2
|
||||||
|
tmp = (y2 - ry) / (x2 - rx);
|
||||||
|
side1 = FG_SIGN (tmp * (x3 - rx) + ry - y3);
|
||||||
|
side2 = FG_SIGN (tmp * (x1 - rx) + ry - y1);
|
||||||
|
if ( side1 != side2 ) {
|
||||||
|
// printf("failed side 3 check\n");
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
|
||||||
|
return true;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int sgdIsectInfLinePlane( sgdVec3 dst, const sgdVec3 l_org,
|
||||||
|
const sgdVec3 l_vec, const sgdVec4 plane )
|
||||||
|
{
|
||||||
|
SGDfloat tmp = sgdScalarProductVec3 ( l_vec, plane ) ;
|
||||||
|
|
||||||
|
/* Is line parallel to plane? */
|
||||||
|
|
||||||
|
if ( fabs ( tmp ) < FLT_EPSILON )
|
||||||
|
return false ;
|
||||||
|
|
||||||
|
sgdScaleVec3 ( dst, l_vec, -( sgdScalarProductVec3 ( l_org, plane )
|
||||||
|
+ plane[3] ) / tmp ) ;
|
||||||
|
sgdAddVec3 ( dst, l_org ) ;
|
||||||
|
|
||||||
|
return true ;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
static void sgdXformPnt3 ( sgdVec3 dst, const sgVec3 src, const sgdMat4 mat )
|
||||||
|
{
|
||||||
|
SGDfloat t0 = src[ 0 ] ;
|
||||||
|
SGDfloat t1 = src[ 1 ] ;
|
||||||
|
SGDfloat t2 = src[ 2 ] ;
|
||||||
|
|
||||||
|
dst[0] = ( t0 * mat[ 0 ][ 0 ] +
|
||||||
|
t1 * mat[ 1 ][ 0 ] +
|
||||||
|
t2 * mat[ 2 ][ 0 ] +
|
||||||
|
mat[ 3 ][ 0 ] ) ;
|
||||||
|
|
||||||
|
dst[1] = ( t0 * mat[ 0 ][ 1 ] +
|
||||||
|
t1 * mat[ 1 ][ 1 ] +
|
||||||
|
t2 * mat[ 2 ][ 1 ] +
|
||||||
|
mat[ 3 ][ 1 ] ) ;
|
||||||
|
|
||||||
|
dst[2] = ( t0 * mat[ 0 ][ 2 ] +
|
||||||
|
t1 * mat[ 1 ][ 2 ] +
|
||||||
|
t2 * mat[ 2 ][ 2 ] +
|
||||||
|
mat[ 3 ][ 2 ] ) ;
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
Find the intersection of an infinite line with a leaf
|
||||||
|
the line being defined by a point and direction.
|
||||||
|
|
||||||
|
Variables
|
||||||
|
In:
|
||||||
|
ssgLeaf pointer -- leaf
|
||||||
|
qualified matrix -- m
|
||||||
|
line origin -- orig
|
||||||
|
line direction -- dir
|
||||||
|
Out:
|
||||||
|
result -- intersection point
|
||||||
|
normal -- intersected tri's normal
|
||||||
|
|
||||||
|
Returns:
|
||||||
|
true if intersection found
|
||||||
|
false otherwise
|
||||||
|
*/
|
||||||
|
int FGHitList::IntersectLeaf( ssgLeaf *leaf, sgdMat4 m,
|
||||||
|
sgdVec3 orig, sgdVec3 dir )
|
||||||
|
{
|
||||||
|
int num_hits = 0;
|
||||||
|
for ( int i = 0; i < leaf->getNumTriangles(); ++i ) {
|
||||||
|
short i1, i2, i3;
|
||||||
|
leaf->getTriangle( i, &i1, &i2, &i3 );
|
||||||
|
|
||||||
|
sgdVec3 tri[3];
|
||||||
|
sgdXformPnt3( tri[0], leaf->getVertex( i1 ), m );
|
||||||
|
sgdXformPnt3( tri[1], leaf->getVertex( i2 ), m );
|
||||||
|
sgdXformPnt3( tri[2], leaf->getVertex( i3 ), m );
|
||||||
|
|
||||||
|
sgdVec4 plane;
|
||||||
|
sgdMakePlane( plane, tri[0], tri[1], tri[2] );
|
||||||
|
|
||||||
|
sgdVec3 point;
|
||||||
|
if( sgdIsectInfLinePlane( point, orig, dir, plane ) ) {
|
||||||
|
if( sgdPointInTriangle( point, tri ) ) {
|
||||||
|
add(leaf,i,point,plane);
|
||||||
|
num_hits++;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
return num_hits;
|
||||||
|
}
|
||||||
|
|
||||||
|
void FGHitList::IntersectBranch( ssgBranch *branch, sgdMat4 m,
|
||||||
|
sgdVec3 orig, sgdVec3 dir )
|
||||||
|
{
|
||||||
|
sgSphere *bsphere;
|
||||||
|
for ( ssgEntity *kid = branch->getKid( 0 );
|
||||||
|
kid != NULL;
|
||||||
|
kid = branch->getNextKid() )
|
||||||
|
{
|
||||||
|
if ( kid->getTraversalMask() & SSGTRAV_HOT ) {
|
||||||
|
bsphere = kid->getBSphere();
|
||||||
|
sgVec3 fcenter;
|
||||||
|
sgCopyVec3( fcenter, bsphere->getCenter() );
|
||||||
|
sgdVec3 center;
|
||||||
|
center[0] = fcenter[0];
|
||||||
|
center[1] = fcenter[1];
|
||||||
|
center[2] = fcenter[2];
|
||||||
|
sgdXformPnt3( center, m ) ;
|
||||||
|
double radius_sqd = bsphere->getRadius() * bsphere->getRadius();
|
||||||
|
if ( sgdPointLineDistSquared( center, orig, dir ) < radius_sqd ) {
|
||||||
|
// possible intersections
|
||||||
|
if ( kid->isAKindOf ( ssgTypeBranch() ) ) {
|
||||||
|
sgdMat4 m_new;
|
||||||
|
sgdCopyMat4(m_new, m);
|
||||||
|
if ( kid->isA( ssgTypeTransform() ) ) {
|
||||||
|
sgMat4 fxform;
|
||||||
|
((ssgTransform *)kid)->getTransform( fxform );
|
||||||
|
sgdMat4 xform;
|
||||||
|
sgdSetMat4( xform, fxform );
|
||||||
|
sgdPreMultMat4( m_new, xform );
|
||||||
|
}
|
||||||
|
IntersectBranch( (ssgBranch *)kid, m_new, orig, dir );
|
||||||
|
} else if ( kid->isAKindOf ( ssgTypeLeaf() ) ) {
|
||||||
|
IntersectLeaf( (ssgLeaf *)kid, m, orig, dir );
|
||||||
|
}
|
||||||
|
} else {
|
||||||
|
// end of the line for this branch
|
||||||
|
}
|
||||||
|
} else {
|
||||||
|
// branch requested not to be traversed
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
// This expects the inital m to the identity transform
|
||||||
|
void ssgGetEntityTransform(ssgEntity *branch, sgMat4 m )
|
||||||
|
{
|
||||||
|
for ( ssgEntity *parent = branch->getParent(0);
|
||||||
|
parent != NULL;
|
||||||
|
parent = parent->getNextParent() )
|
||||||
|
{
|
||||||
|
// recurse till we are at the scene root
|
||||||
|
// then just unwinding the stack should
|
||||||
|
// give us our cumulative transform :-) NHV
|
||||||
|
ssgGetEntityTransform( parent, m );
|
||||||
|
if ( parent->isA( ssgTypeTransform() ) ) {
|
||||||
|
sgMat4 xform;
|
||||||
|
((ssgTransform *)parent)->getTransform( xform );
|
||||||
|
sgPreMultMat4( m, xform );
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
// return the passed entitity's bsphere's center point radius and
|
||||||
|
// fully formed current model matrix for entity
|
||||||
|
void ssgGetCurrentBSphere( ssgEntity *entity, sgVec3 center,
|
||||||
|
float *radius, sgMat4 m )
|
||||||
|
{
|
||||||
|
sgSphere *bsphere = entity->getBSphere();
|
||||||
|
*radius = (double)bsphere->getRadius();
|
||||||
|
sgCopyVec3( center, bsphere->getCenter() );
|
||||||
|
sgMakeIdentMat4 ( m ) ;
|
||||||
|
ssgGetEntityTransform( entity, m );
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
void FGHitList::IntersectCachedLeaf( sgdMat4 m,
|
||||||
|
sgdVec3 orig, sgdVec3 dir)
|
||||||
|
{
|
||||||
|
if ( last_hit() ) {
|
||||||
|
float radius;
|
||||||
|
sgVec3 fcenter;
|
||||||
|
sgMat4 fxform;
|
||||||
|
// ssgEntity *ent = last_hit();
|
||||||
|
ssgGetCurrentBSphere( last_hit(), fcenter, &radius, fxform );
|
||||||
|
sgdMat4 m;
|
||||||
|
sgdVec3 center;
|
||||||
|
sgdSetMat4( m, fxform );
|
||||||
|
sgdXformPnt3( center, m );
|
||||||
|
|
||||||
|
if ( sgdPointLineDistSquared( center, orig, dir ) < radius*radius ) {
|
||||||
|
IntersectLeaf( (ssgLeaf *)last_hit(), m, orig, dir );
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
96
src/Scenery/hitlist.hxx
Normal file
96
src/Scenery/hitlist.hxx
Normal file
|
@ -0,0 +1,96 @@
|
||||||
|
#ifndef _HITLIST_HXX
|
||||||
|
#define _HITLIST_HXX
|
||||||
|
|
||||||
|
#ifndef __cplusplus
|
||||||
|
# error This library requires C++
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include <simgear/compiler.h>
|
||||||
|
|
||||||
|
#include <vector>
|
||||||
|
|
||||||
|
#include <plib/ssg.h>
|
||||||
|
|
||||||
|
FG_USING_STD(vector);
|
||||||
|
|
||||||
|
|
||||||
|
class FGHitRec {
|
||||||
|
|
||||||
|
private:
|
||||||
|
ssgEntity *ent;
|
||||||
|
int index;
|
||||||
|
sgdVec3 point;
|
||||||
|
sgdVec3 normal;
|
||||||
|
|
||||||
|
public:
|
||||||
|
|
||||||
|
FGHitRec( ssgEntity *e, int idx, sgdVec3 p, sgdVec3 n ) {
|
||||||
|
ent = e;
|
||||||
|
index = idx;
|
||||||
|
sgdSetVec3(point,p[0],p[1],p[2]);
|
||||||
|
sgdSetVec3(normal,n[0],n[1],n[2]);
|
||||||
|
}
|
||||||
|
|
||||||
|
ssgEntity *get_entity(void) { return ent; }
|
||||||
|
int get_face(void) { return index; }
|
||||||
|
double *get_point(void) { return point; }
|
||||||
|
double *get_normal(void) { return normal; }
|
||||||
|
};
|
||||||
|
|
||||||
|
|
||||||
|
class FGHitList {
|
||||||
|
|
||||||
|
private:
|
||||||
|
|
||||||
|
ssgEntity *last;
|
||||||
|
vector < FGHitRec > list;
|
||||||
|
|
||||||
|
public:
|
||||||
|
|
||||||
|
FGHitList() { last = NULL; }
|
||||||
|
void init(void) { list.clear(); }
|
||||||
|
void clear(void) { init(); last = NULL; }
|
||||||
|
void add( ssgEntity *ent, int idx, sgdVec3 point, sgdVec3 normal ) {
|
||||||
|
list.push_back( FGHitRec( ent,idx,point,normal) );
|
||||||
|
last = ent;
|
||||||
|
}
|
||||||
|
int num_hits(void) { return list.size(); }
|
||||||
|
ssgEntity *get_entity(int i) { return list[i].get_entity(); }
|
||||||
|
ssgEntity *last_hit(void) { return last; }
|
||||||
|
int get_face(int i) { return list[i].get_face(); }
|
||||||
|
double *get_point(int i) { return list[i].get_point(); }
|
||||||
|
double *get_normal(int i) { return list[i].get_normal(); }
|
||||||
|
|
||||||
|
void Intersect( ssgBranch *branch,
|
||||||
|
sgdVec3 orig, sgdVec3 dir );
|
||||||
|
|
||||||
|
void IntersectBranch( ssgBranch *branch, sgdMat4 m,
|
||||||
|
sgdVec3 orig, sgdVec3 dir);
|
||||||
|
|
||||||
|
void IntersectCachedLeaf( sgdMat4 m,
|
||||||
|
sgdVec3 orig, sgdVec3 dir);
|
||||||
|
|
||||||
|
int IntersectLeaf( ssgLeaf *leaf, sgdMat4 m,
|
||||||
|
sgdVec3 orig, sgdVec3 dir );
|
||||||
|
};
|
||||||
|
|
||||||
|
|
||||||
|
inline void FGHitList::Intersect( ssgBranch *scene,
|
||||||
|
sgdVec3 orig, sgdVec3 dir )
|
||||||
|
{
|
||||||
|
sgdMat4 m;
|
||||||
|
|
||||||
|
init();
|
||||||
|
|
||||||
|
if( last_hit() ) {
|
||||||
|
sgdMakeIdentMat4 ( m ) ;
|
||||||
|
IntersectCachedLeaf(m, orig, dir);
|
||||||
|
}
|
||||||
|
if( ! num_hits() ) {
|
||||||
|
clear();
|
||||||
|
sgdMakeIdentMat4 ( m ) ;
|
||||||
|
IntersectBranch( scene, m, orig, dir);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif // _HITLIST_HXX
|
Loading…
Add table
Reference in a new issue