/// <summary>
/// Add a point to the polygon or polyline.
/// </summary>
/// <param name="g">The geod_geodesic object specifying the ellipsoid.</param>
/// <param name="p">The geod_polygon object specifying the polygon.</param>
/// <param name="lat">The latitude of the point (degrees).</param>
/// <param name="lon">The longitude of the point (degrees).</param>
/// <remarks>
/// g and p must have been initialized with calls to geod_init() and
/// geod_polygon_init(), respectively. The same g must be used for all the
/// points and edges in a polygon. lat should be in the range
/// [-90deg, 90deg] and lon should be in the range [-540deg, 540deg).
/// </remarks>
public void geod_polygon_addpoint(geod_geodesic g, double lat, double lon)
{
lon = AngNormalize(lon);
if (num == 0)
{
lat0 = this.lat = lat;
lon0 = this.lon = lon;
}
else
{
double s12, S12 = 0, dummy;
if (polyline)
{
g.geod_geninverse(this.lat, this.lon, lat, lon, GEOD.DISTANCE, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out dummy);
}
else
{
g.geod_geninverse(this.lat, this.lon, lat, lon, GEOD.DISTANCE | GEOD.AREA, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
}
accadd(P, s12);
if (!polyline)
{
accadd(A, S12);
crossings += transit(this.lon, lon);
}
this.lat = lat; this.lon = lon;
}
++num;
}
/// <summary>
/// Return the results assuming a tentative final test point is added via an
/// azimuth and distance; however, the data for the test point is not saved.
/// This lets you report a running result for the perimeter and area as the
/// user moves the mouse cursor. Ordinary floating point arithmetic is used
/// to accumulate the data for the test point; thus the area and perimeter
/// returned are less accurate than if geod_polygon_addedge() and
/// geod_polygon_compute() are used.
/// </summary>
/// <param name="g">The geod_geodesic object specifying the ellipsoid.</param>
/// <param name="p">The geod_polygon object specifying the polygon.</param>
/// <param name="azi">The azimuth at current point (degrees).</param>
/// <param name="s">The distance from current point to final test point (meters).</param>
/// <param name="reverse">If set <b>true</b> then clockwise (instead of counter-clockwise)
/// traversal counts as a positive area.</param>
/// <param name="sign">If set <b>true</b> then return a signed result for the area if the
/// polygon is traversed in the "wrong" direction instead of returning the area for the
/// rest of the earth.</param>
/// <param name="pA">The area of the polygon (square meters); only set if polyline is set <b>true</b>
/// in the call to geod_polygon_init().</param>
/// <param name="pP">The perimeter of the polygon or length of the polyline (meters).</param>
/// <returns>The number of points.</returns>
/// <remarks>
/// azi should be in the range [-540deg, 540deg).
/// </remarks>
public int geod_polygon_testedge(geod_geodesic g, double azi, double s, bool reverse, bool sign, out double pA, out double pP)
{
pP = pA = NaN;
int num = this.num + 1;
if (num == 1)
{
return(0); // we don't have a starting point!
}
double perimeter = P[0] + s;
if (polyline)
{
pP = perimeter;
return(num);
}
double tempsum = A[0];
int crossings = this.crossings;
{
double lat, lon, s12, S12, dummy;
g.geod_gendirect(this.lat, this.lon, azi, GEOD.LONG_UNROLL, s, GEOD.LATITUDE | GEOD.LONGITUDE | GEOD.AREA, out lat, out lon, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
tempsum += S12;
crossings += transitdirect(this.lon, lon);
g.geod_geninverse(lat, lon, lat0, lon0, GEOD.DISTANCE | GEOD.AREA, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
perimeter += s12;
tempsum += S12;
crossings += transit(lon, lon0);
}
double area0 = 4 * pi * g.c2;
if ((crossings & 1) != 0)
{
tempsum += (tempsum < 0?1:-1) * area0 / 2;
}
// area is with the clockwise sense. If !reverse convert to counter-clockwise convention.
if (!reverse)
{
tempsum *= -1;
}
// If sign put area in (-area0/2, area0/2], else put area in [0, area0)
if (sign)
{
if (tempsum > area0 / 2)
{
tempsum -= area0;
}
else if (tempsum <= -area0 / 2)
{
tempsum += area0;
}
}
else
{
if (tempsum >= area0)
{
tempsum -= area0;
}
else if (tempsum < 0)
{
tempsum += area0;
}
}
pP = perimeter;
pA = 0 + tempsum;
return(num);
}
/// <summary>
/// Return the results assuming a tentative final test point is added;
/// however, the data for the test point is not saved. This lets you report a
/// running result for the perimeter and area as the user moves the mouse
/// cursor. Ordinary floating point arithmetic is used to accumulate the data
/// for the test point; thus the area and perimeter returned are less accurate
/// than if geod_polygon_addpoint() and geod_polygon_compute() are used.
/// </summary>
/// <param name="g">The geod_geodesic object specifying the ellipsoid.</param>
/// <param name="p">The geod_polygon object specifying the polygon.</param>
/// <param name="lat">The latitude of the test point (degrees).</param>
/// <param name="lon">The longitude of the test point (degrees).</param>
/// <param name="reverse">If set <b>true</b> then clockwise (instead of counter-clockwise)
/// traversal counts as a positive area.</param>
/// <param name="sign">If set <b>true</b> then return a signed result for the area if the
/// polygon is traversed in the "wrong" direction instead of returning the area for the
/// rest of the earth.</param>
/// <param name="pA">The area of the polygon (square meters); only set if polyline is set <b>true</b>
/// in the call to geod_polygon_init().</param>
/// <param name="pP">The perimeter of the polygon or length of the polyline (meters).</param>
/// <returns>The number of points.</returns>
/// <remarks>
/// lat should be in the range [-90deg, 90deg] and lon should be in the range [-540deg, 540deg).
/// </remarks>
public int geod_polygon_testpoint(geod_geodesic g, double lat, double lon, bool reverse, bool sign, out double pA, out double pP)
{
pP = pA = 0;
int num = this.num + 1;
if (num == 1)
{
return(num);
}
double perimeter = P[0];
double tempsum = polyline?0:A[0];
int crossings = this.crossings;
for (int i = 0; i < (polyline?1:2); ++i)
{
double s12, dummy;
if (!polyline)
{
double S12;
g.geod_geninverse(i == 0?this.lat:lat, i == 0?this.lon:lon, i != 0?lat0:lat, i != 0?lon0:lon, GEOD.DISTANCE | GEOD.AREA, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
tempsum += S12;
crossings += transit(i == 0?this.lon:lon, i != 0?this.lon0:lon);
}
else
{
g.geod_geninverse(i == 0?this.lat:lat, i == 0?this.lon:lon, i != 0?lat0:lat, i != 0?lon0:lon, GEOD.DISTANCE, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out dummy);
}
perimeter += s12;
}
pP = perimeter;
if (polyline)
{
return(num);
}
double area0 = 4 * pi * g.c2;
if ((crossings & 1) != 0)
{
tempsum += (tempsum < 0?1:-1) * area0 / 2;
}
// area is with the clockwise sense. If !reverse convert to counter-clockwise convention.
if (!reverse)
{
tempsum *= -1;
}
// If sign put area in (-area0/2, area0/2], else put area in [0, area0)
if (sign)
{
if (tempsum > area0 / 2)
{
tempsum -= area0;
}
else if (tempsum <= -area0 / 2)
{
tempsum += area0;
}
}
else
{
if (tempsum >= area0)
{
tempsum -= area0;
}
else if (tempsum < 0)
{
tempsum += area0;
}
}
pA = 0 + tempsum;
return(num);
}
/// <summary>
/// Return the results for a polygon.
/// </summary>
/// <param name="g">The geod_geodesic object specifying the ellipsoid.</param>
/// <param name="p">The geod_polygon object specifying the polygon.</param>
/// <param name="reverse">If set <b>true</b> then clockwise (instead of counter-clockwise)
/// traversal counts as a positive area.</param>
/// <param name="sign">If set <b>true</b> then return a signed result for the area if the
/// polygon is traversed in the "wrong" direction instead of returning the area for the
/// rest of the earth.</param>
/// <param name="pA">The area of the polygon (square meters); only set if polyline is set <b>true</b>
/// in the call to geod_polygon_init().</param>
/// <param name="pP">The perimeter of the polygon or length of the polyline (meters).</param>
/// <returns>The number of points.</returns>
/// <remarks>
/// The area and perimeter are accumulated at two times the standard floating
/// point precision to guard against the loss of accuracy with many-sided
/// polygons. Only simple polygons (which are not self-intersecting) are
/// allowed. There's no need to "close" the polygon by repeating the first vertex.
/// </remarks>
public int geod_polygon_compute(geod_geodesic g, bool reverse, bool sign, out double pA, out double pP)
{
pP = pA = 0;
if (num < 2)
{
return(num);
}
if (polyline)
{
pP = P[0];
return(num);
}
double s12, S12, dummy;
g.geod_geninverse(lat, lon, lat0, lon0, GEOD.DISTANCE | GEOD.AREA, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
pP = accsum(P, s12);
double[] t = new double[2];
acccopy(A, t);
accadd(t, S12);
int crossings = this.crossings + transit(lon, lon0);
double area0 = 4 * pi * g.c2;
if ((crossings & 1) != 0)
{
accadd(t, (t[0] < 0?1:-1) * area0 / 2);
}
// area is with the clockwise sense. If !reverse convert to
// counter-clockwise convention.
if (!reverse)
{
accneg(t);
}
// If sign put area in (-area0/2, area0/2], else put area in [0, area0)
if (sign)
{
if (t[0] > area0 / 2)
{
accadd(t, -area0);
}
else if (t[0] <= -area0 / 2)
{
accadd(t, +area0);
}
}
else
{
if (t[0] >= area0)
{
accadd(t, -area0);
}
else if (t[0] < 0)
{
accadd(t, +area0);
}
}
pA = 0 + t[0];
return(num);
}
/// <summary>
/// Return the results assuming a tentative final test point is added;
/// however, the data for the test point is not saved. This lets you report a
/// running result for the perimeter and area as the user moves the mouse
/// cursor. Ordinary floating point arithmetic is used to accumulate the data
/// for the test point; thus the area and perimeter returned are less accurate
/// than if geod_polygon_addpoint() and geod_polygon_compute() are used.
/// </summary>
/// <param name="g">The geod_geodesic object specifying the ellipsoid.</param>
/// <param name="p">The geod_polygon object specifying the polygon.</param>
/// <param name="lat">The latitude of the test point (degrees).</param>
/// <param name="lon">The longitude of the test point (degrees).</param>
/// <param name="reverse">If set <b>true</b> then clockwise (instead of counter-clockwise)
/// traversal counts as a positive area.</param>
/// <param name="sign">If set <b>true</b> then return a signed result for the area if the
/// polygon is traversed in the "wrong" direction instead of returning the area for the
/// rest of the earth.</param>
/// <param name="pA">The area of the polygon (square meters); only set if polyline is set <b>true</b>
/// in the call to geod_polygon_init().</param>
/// <param name="pP">The perimeter of the polygon or length of the polyline (meters).</param>
/// <returns>The number of points.</returns>
/// <remarks>
/// lat should be in the range [-90deg, 90deg] and lon should be in the range [-540deg, 540deg).
/// </remarks>
public int geod_polygon_testpoint(geod_geodesic g, double lat, double lon, bool reverse, bool sign, out double pA, out double pP)
{
pP=pA=0;
int num=this.num+1;
if(num==1) return num;
double perimeter=P[0];
double tempsum=polyline?0:A[0];
int crossings=this.crossings;
for(int i=0; i<(polyline?1:2); ++i)
{
double s12, dummy;
if(!polyline)
{
double S12;
g.geod_geninverse(i==0?this.lat:lat, i==0?this.lon:lon, i!=0?lat0:lat, i!=0?lon0:lon, GEOD.DISTANCE|GEOD.AREA, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
tempsum+=S12;
crossings+=transit(i==0?this.lon:lon, i!=0?this.lon0:lon);
}
else g.geod_geninverse(i==0?this.lat:lat, i==0?this.lon:lon, i!=0?lat0:lat, i!=0?lon0:lon, GEOD.DISTANCE, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out dummy);
perimeter+=s12;
}
pP=perimeter;
if(polyline) return num;
double area0=4*pi*g.c2;
if((crossings&1)!=0) tempsum+=(tempsum<0?1:-1)*area0/2;
// area is with the clockwise sense. If !reverse convert to counter-clockwise convention.
if(!reverse) tempsum*=-1;
// If sign put area in (-area0/2, area0/2], else put area in [0, area0)
if(sign)
{
if(tempsum>area0/2) tempsum-=area0;
else if(tempsum<=-area0/2) tempsum+=area0;
}
else
{
if(tempsum>=area0) tempsum-=area0;
else if(tempsum<0) tempsum+=area0;
}
pA=0+tempsum;
return num;
}
/// <summary>
/// Return the results assuming a tentative final test point is added via an
/// azimuth and distance; however, the data for the test point is not saved.
/// This lets you report a running result for the perimeter and area as the
/// user moves the mouse cursor. Ordinary floating point arithmetic is used
/// to accumulate the data for the test point; thus the area and perimeter
/// returned are less accurate than if geod_polygon_addedge() and
/// geod_polygon_compute() are used.
/// </summary>
/// <param name="g">The geod_geodesic object specifying the ellipsoid.</param>
/// <param name="p">The geod_polygon object specifying the polygon.</param>
/// <param name="azi">The azimuth at current point (degrees).</param>
/// <param name="s">The distance from current point to final test point (meters).</param>
/// <param name="reverse">If set <b>true</b> then clockwise (instead of counter-clockwise)
/// traversal counts as a positive area.</param>
/// <param name="sign">If set <b>true</b> then return a signed result for the area if the
/// polygon is traversed in the "wrong" direction instead of returning the area for the
/// rest of the earth.</param>
/// <param name="pA">The area of the polygon (square meters); only set if polyline is set <b>true</b>
/// in the call to geod_polygon_init().</param>
/// <param name="pP">The perimeter of the polygon or length of the polyline (meters).</param>
/// <returns>The number of points.</returns>
/// <remarks>
/// azi should be in the range [-540deg, 540deg).
/// </remarks>
public int geod_polygon_testedge(geod_geodesic g, double azi, double s, bool reverse, bool sign, out double pA, out double pP)
{
pP=pA=NaN;
int num=this.num+1;
if(num==1) return 0; // we don't have a starting point!
double perimeter=P[0]+s;
if(polyline)
{
pP=perimeter;
return num;
}
double tempsum=A[0];
int crossings=this.crossings;
{
double lat, lon, s12, S12, dummy;
g.geod_gendirect(this.lat, this.lon, azi, GEOD.LONG_UNROLL, s, GEOD.LATITUDE|GEOD.LONGITUDE|GEOD.AREA, out lat, out lon, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
tempsum+=S12;
crossings+=transitdirect(this.lon, lon);
g.geod_geninverse(lat, lon, lat0, lon0, GEOD.DISTANCE|GEOD.AREA, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
perimeter+=s12;
tempsum+=S12;
crossings+=transit(lon, lon0);
}
double area0=4*pi*g.c2;
if((crossings&1)!=0) tempsum+=(tempsum<0?1:-1)*area0/2;
// area is with the clockwise sense. If !reverse convert to counter-clockwise convention.
if(!reverse) tempsum*=-1;
// If sign put area in (-area0/2, area0/2], else put area in [0, area0)
if(sign)
{
if(tempsum>area0/2) tempsum-=area0;
else if(tempsum<=-area0/2) tempsum+=area0;
}
else
{
if(tempsum>=area0) tempsum-=area0;
else if(tempsum<0) tempsum+=area0;
}
pP=perimeter;
pA=0+tempsum;
return num;
}
/// <summary>
/// Return the results for a polygon.
/// </summary>
/// <param name="g">The geod_geodesic object specifying the ellipsoid.</param>
/// <param name="p">The geod_polygon object specifying the polygon.</param>
/// <param name="reverse">If set <b>true</b> then clockwise (instead of counter-clockwise)
/// traversal counts as a positive area.</param>
/// <param name="sign">If set <b>true</b> then return a signed result for the area if the
/// polygon is traversed in the "wrong" direction instead of returning the area for the
/// rest of the earth.</param>
/// <param name="pA">The area of the polygon (square meters); only set if polyline is set <b>true</b>
/// in the call to geod_polygon_init().</param>
/// <param name="pP">The perimeter of the polygon or length of the polyline (meters).</param>
/// <returns>The number of points.</returns>
/// <remarks>
/// The area and perimeter are accumulated at two times the standard floating
/// point precision to guard against the loss of accuracy with many-sided
/// polygons. Only simple polygons (which are not self-intersecting) are
/// allowed. There's no need to "close" the polygon by repeating the first vertex.
/// </remarks>
public int geod_polygon_compute(geod_geodesic g, bool reverse, bool sign, out double pA, out double pP)
{
pP=pA=0;
if(num<2) return num;
if(polyline)
{
pP=P[0];
return num;
}
double s12, S12, dummy;
g.geod_geninverse(lat, lon, lat0, lon0, GEOD.DISTANCE|GEOD.AREA, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
pP=accsum(P, s12);
double[] t=new double[2];
acccopy(A, t);
accadd(t, S12);
int crossings=this.crossings+transit(lon, lon0);
double area0=4*pi*g.c2;
if((crossings&1)!=0) accadd(t, (t[0]<0?1:-1)*area0/2);
// area is with the clockwise sense. If !reverse convert to
// counter-clockwise convention.
if(!reverse) accneg(t);
// If sign put area in (-area0/2, area0/2], else put area in [0, area0)
if(sign)
{
if(t[0]>area0/2) accadd(t, -area0);
else if(t[0]<=-area0/2) accadd(t, +area0);
}
else
{
if(t[0]>=area0) accadd(t, -area0);
else if(t[0]<0) accadd(t, +area0);
}
pA=0+t[0];
return num;
}
/// <summary>
/// Add a point to the polygon or polyline.
/// </summary>
/// <param name="g">The geod_geodesic object specifying the ellipsoid.</param>
/// <param name="p">The geod_polygon object specifying the polygon.</param>
/// <param name="lat">The latitude of the point (degrees).</param>
/// <param name="lon">The longitude of the point (degrees).</param>
/// <remarks>
/// g and p must have been initialized with calls to geod_init() and
/// geod_polygon_init(), respectively. The same g must be used for all the
/// points and edges in a polygon. lat should be in the range
/// [-90deg, 90deg] and lon should be in the range [-540deg, 540deg).
/// </remarks>
public void geod_polygon_addpoint(geod_geodesic g, double lat, double lon)
{
lon=AngNormalize(lon);
if(num==0)
{
lat0=this.lat=lat;
lon0=this.lon=lon;
}
else
{
double s12, S12=0, dummy;
if(polyline) g.geod_geninverse(this.lat, this.lon, lat, lon, GEOD.DISTANCE, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out dummy);
else g.geod_geninverse(this.lat, this.lon, lat, lon, GEOD.DISTANCE|GEOD.AREA, out s12, out dummy, out dummy, out dummy, out dummy, out dummy, out S12);
accadd(P, s12);
if(!polyline)
{
accadd(A, S12);
crossings+=transit(this.lon, lon);
}
this.lat=lat; this.lon=lon;
}
++num;
}
