osg::ref_ptr<osg::Group> BuildGeoBoundsNode(std::string const &name,
GeoBounds const &b,
osg::Vec4 const &color,
double min_angle,
int level_offset)
{
static const double k_eps = 1E-8;
double const lon_delta = b.maxLon-b.minLon;
double const lat_delta = b.maxLat-b.minLat;
if((lon_delta < k_eps) ||
(lat_delta < k_eps)) {
osg::ref_ptr<osg::Group> gp = new osg::Group;
gp->setName(name);
return gp;
}
double const lon_div = (b.maxLon - b.minLon)/min_angle;
double const lat_div = (b.maxLat - b.minLat)/min_angle;
std::vector<osg::Vec3d> list_ecef;
// left edge
for(double lat=b.maxLat; lat >= b.minLat; lat-=lat_div) {
LLA lla; lla.lon = b.minLon; lla.lat = lat; lla.alt = 0;
list_ecef.push_back(ConvLLAToECEF(lla));
}
// bottom edge
for(double lon=b.minLon; lon <= b.maxLon; lon+=lon_div) {
LLA lla; lla.lon = lon; lla.lat = b.minLat; lla.alt = 0;
list_ecef.push_back(ConvLLAToECEF(lla));
}
// right edge
for(double lat=b.minLat; lat <= b.maxLat; lat+=lat_div) {
LLA lla; lla.lon = b.maxLon; lla.lat = lat; lla.alt = 0;
list_ecef.push_back(ConvLLAToECEF(lla));
}
// top edge
for(double lon=b.maxLon; lon >= b.minLon; lon-=lon_div) {
LLA lla; lla.lon = lon; lla.lat = b.maxLat; lla.alt = 0;
list_ecef.push_back(ConvLLAToECEF(lla));
}
osg::ref_ptr<osg::Group> gp = BuildSurfacePolyNode(name,list_ecef,color,0.0,level_offset);
return gp;
}
TileSetLLByPixelArea::Eval::Eval(GeoBounds const &bounds,
osg::Matrixd const &mvp,
double min_angle_degs)
{
uint32_t lon_segments = std::max((bounds.maxLon-bounds.minLon)/min_angle_degs,1.0);
uint32_t lat_segments = std::max((bounds.maxLat-bounds.minLat)/min_angle_degs,1.0);
BuildEarthSurface(bounds.minLon,
bounds.maxLon,
bounds.minLat,
bounds.maxLat,
lon_segments,
lat_segments,
list_lla,
list_vx,
list_ix);
// get the ndc for each vertex
bool ok;
list_ndc.reserve(list_vx.size());
for(auto const &vx : list_vx) {
list_ndc.push_back(ConvWorldToNDC(mvp,vx,ok));
}
// calculate the normals for each quad
list_quad_nx.clear();
list_quad_nx.reserve(list_ix.size()/6);
for(size_t i=0; i < list_ix.size(); i+=6) {
// 6 vx per quad (2 tris)
// the normal of any tri == the quad normal
// since this is a 'flat' quad
osg::Vec3d const &v0 = list_vx[list_ix[i+0]];
osg::Vec3d const &v1 = list_vx[list_ix[i+1]];
osg::Vec3d const &v2 = list_vx[list_ix[i+2]];
list_quad_nx.push_back((v1-v0)^(v2-v0));
list_quad_nx.back().normalize();
}
// lon and lat planes
plane_min_lon = CalcLonPlane(bounds.minLon,true,true);
plane_max_lon = CalcLonPlane(bounds.maxLon,false,true);
plane_min_lat = CalcLatPlane(bounds.minLat,false);
plane_max_lat = CalcLatPlane(bounds.maxLat,true);
// (mid lon,mid lat) ecef
LLA lla_mid;
lla_mid.lon = (bounds.minLon+bounds.maxLon)*0.5;
lla_mid.lat = (bounds.minLat+bounds.maxLat)*0.5;
lla_mid.alt = 0.0;
ecef_mid = ConvLLAToECEF(lla_mid);
}
VxTile * BuildRootTile(uint8_t const level,
double const minLon,
double const minLat,
double const maxLon,
double const maxLat)
{
VxTile * t = new VxTile;
t->level = level;
t->minLon = minLon;
t->minLat = minLat;
t->maxLon = maxLon;
t->maxLat = maxLat;
t->midLon = (minLon+maxLon)*0.5;
t->midLat = (minLat+maxLat)*0.5;
t->p_ecef_LT = new osg::Vec3d;
*(t->p_ecef_LT) = ConvLLAToECEF(PointLLA(minLon,maxLat));
t->p_ecef_LB = new osg::Vec3d;
*(t->p_ecef_LB) = ConvLLAToECEF(PointLLA(minLon,minLat));
t->p_ecef_RB = new osg::Vec3d;
*(t->p_ecef_RB) = ConvLLAToECEF(PointLLA(maxLon,minLat));
t->p_ecef_RT = new osg::Vec3d;
*(t->p_ecef_RT) = ConvLLAToECEF(PointLLA(maxLon,maxLat));
t->ecef_LM = ConvLLAToECEF(PointLLA(minLon,t->midLat));
t->ecef_MB = ConvLLAToECEF(PointLLA(t->midLon,minLat));
t->ecef_RM = ConvLLAToECEF(PointLLA(maxLon,t->midLat));
t->ecef_MT = ConvLLAToECEF(PointLLA(t->midLon,maxLat));
t->ecef_MM = ConvLLAToECEF(PointLLA(t->midLon,t->midLat));
CalcTileOBB(t);
return t;
}
std::unique_ptr<VxTile> BuildChildTile(VxTile * parent,
uint8_t const quadrant)
{
std::unique_ptr<VxTile> t(new VxTile);
if(quadrant == 0) {
// LT
t->minLon = parent->minLon;
t->maxLon = parent->midLon;
t->minLat = parent->midLat;
t->maxLat = parent->maxLat;
t->p_ecef_LT = parent->p_ecef_LT;
t->p_ecef_LB = &(parent->ecef_LM);
t->p_ecef_RB = &(parent->ecef_MM);
t->p_ecef_RT = &(parent->ecef_MT);
}
else if(quadrant == 1) {
// LB
t->minLon = parent->minLon;
t->maxLon = parent->midLon;
t->minLat = parent->minLat;
t->maxLat = parent->midLat;
t->p_ecef_LT = &(parent->ecef_LM);
t->p_ecef_LB = parent->p_ecef_LB;
t->p_ecef_RB = &(parent->ecef_MB);
t->p_ecef_RT = &(parent->ecef_MM);
}
else if(quadrant == 2) {
// RB
t->minLon = parent->midLon;
t->maxLon = parent->maxLon;
t->minLat = parent->minLat;
t->maxLat = parent->midLat;
t->p_ecef_LT = &(parent->ecef_MM);
t->p_ecef_LB = &(parent->ecef_MB);
t->p_ecef_RB = parent->p_ecef_RB;
t->p_ecef_RT = &(parent->ecef_RM);
}
else {
// RT
t->minLon = parent->midLon;
t->maxLon = parent->maxLon;
t->minLat = parent->midLat;
t->maxLat = parent->maxLat;
t->p_ecef_LT = &(parent->ecef_MT);
t->p_ecef_LB = &(parent->ecef_MM);
t->p_ecef_RB = &(parent->ecef_RM);
t->p_ecef_RT = parent->p_ecef_RT;
}
t->level = parent->level + 1;
t->midLon = (t->minLon+t->maxLon)*0.5;
t->midLat = (t->minLat+t->maxLat)*0.5;
t->ecef_LM = ConvLLAToECEF(PointLLA(t->minLon,t->midLat));
t->ecef_MB = ConvLLAToECEF(PointLLA(t->midLon,t->minLat));
t->ecef_RM = ConvLLAToECEF(PointLLA(t->maxLon,t->midLat));
t->ecef_MT = ConvLLAToECEF(PointLLA(t->midLon,t->maxLat));
t->ecef_MM = ConvLLAToECEF(PointLLA(t->midLon,t->midLat));
CalcTileOBB(t.get());
return t;
}