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For smoothing things like rivers or roads we need to allow some slope.

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Originally I through together a really cheap/ugly hack for estimating
distance between two points, but that really started to stink when throwing
a lot of new situations at it.  So now I calculate spherical distances between
two points in meters which is plenty accurate for these purposes.  This gives
us much better control over smoothing.  For instance we could establish a
maximum 10% grade for all roads if we wanted to.
This commit is contained in:
curt 2003-09-04 18:53:53 +00:00
parent db7780d1c8
commit 9a7173d85e
1 changed files with 29 additions and 12 deletions
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41
src/BuildTiles/Main/main.cxx
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@ -545,6 +545,23 @@ static double distance2D( const Point3D p1, const Point3D p2 ) {
} }
// calculate spherical distance between two points (lon, lat specified
// in degrees, result returned in meters)
static double distanceSphere( const Point3D p1, const Point3D p2 ) {
Point3D r1( p1.x() * SG_DEGREES_TO_RADIANS,
p1.y() * SG_DEGREES_TO_RADIANS,
p1.z() );
Point3D r2( p2.x() * SG_DEGREES_TO_RADIANS,
p2.y() * SG_DEGREES_TO_RADIANS,
p2.z() );
double course, dist_m;
calc_gc_course_dist( r1, r2, &course, &dist_m );
return dist_m;
}
// fix the elevations of the geodetic nodes // fix the elevations of the geodetic nodes
static void fix_point_heights( TGConstruct& c, const TGArray& array ) static void fix_point_heights( TGConstruct& c, const TGArray& array )
{ {
@ -619,13 +636,13 @@ static void fix_point_heights( TGConstruct& c, const TGArray& array )
if ( e2 < min ) { min = e2; p = raw_nodes[n2]; } if ( e2 < min ) { min = e2; p = raw_nodes[n2]; }
if ( e3 < min ) { min = e3; p = raw_nodes[n3]; } if ( e3 < min ) { min = e3; p = raw_nodes[n3]; }
double d1 = distance2D( p, raw_nodes[n1] ); double d1 = distanceSphere( p, raw_nodes[n1] );
double d2 = distance2D( p, raw_nodes[n2] ); double d2 = distanceSphere( p, raw_nodes[n2] );
double d3 = distance2D( p, raw_nodes[n3] ); double d3 = distanceSphere( p, raw_nodes[n3] );
double max1 = 1000.0 * d1 + min; double max1 = d1 * 0.20 + min;
double max2 = 1000.0 * d2 + min; double max2 = d2 * 0.20 + min;
double max3 = 1000.0 * d3 + min; double max3 = d3 * 0.20 + min;
if ( max1 < e1 ) { raw_nodes[n1].setz( max1 ); } if ( max1 < e1 ) { raw_nodes[n1].setz( max1 ); }
if ( max2 < e2 ) { raw_nodes[n2].setz( max2 ); } if ( max2 < e2 ) { raw_nodes[n2].setz( max2 ); }
@ -640,13 +657,13 @@ static void fix_point_heights( TGConstruct& c, const TGArray& array )
if ( e2 < min ) { min = e2; p = raw_nodes[n2]; } if ( e2 < min ) { min = e2; p = raw_nodes[n2]; }
if ( e3 < min ) { min = e3; p = raw_nodes[n3]; } if ( e3 < min ) { min = e3; p = raw_nodes[n3]; }
double d1 = distance2D( p, raw_nodes[n1] ); double d1 = distanceSphere( p, raw_nodes[n1] );
double d2 = distance2D( p, raw_nodes[n2] ); double d2 = distanceSphere( p, raw_nodes[n2] );
double d3 = distance2D( p, raw_nodes[n3] ); double d3 = distanceSphere( p, raw_nodes[n3] );
double max1 = 400.0 * d1 + min; double max1 = d1 * 0.30 + min;
double max2 = 400.0 * d2 + min; double max2 = d2 * 0.30 + min;
double max3 = 400.0 * d3 + min; double max3 = d3 * 0.30 + min;
if ( max1 < e1 ) { raw_nodes[n1].setz( max1 ); } if ( max1 < e1 ) { raw_nodes[n1].setz( max1 ); }
if ( max2 < e2 ) { raw_nodes[n2].setz( max2 ); } if ( max2 < e2 ) { raw_nodes[n2].setz( max2 ); }