public override Rectangle CalcBoxByDistFromPt(Point @from, double distance, SpatialContext ctx)
{
Debug.Assert(radius == ctx.GetUnits().EarthRadius());
if (distance == 0)
return from.GetBoundingBox();
return DistanceUtils.CalcBoxByDistFromPtDEG(from.GetY(), from.GetX(), distance, ctx);
}
public static Rectangle CalcBoxByDistFromPtDEG(double lat, double lon, double distance, SpatialContext ctx)
{
//See http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates Section 3.1, 3.2 and 3.3
double radius = ctx.GetUnits().EarthRadius();
double dist_deg = Dist2Degrees(distance, radius);
if (dist_deg == 0)
return ctx.MakeRect(lon, lon, lat, lat);//essentially a point
if (dist_deg >= 180)//distance is >= opposite side of the globe
return ctx.GetWorldBounds();
//--calc latitude bounds
double latN_deg = lat + dist_deg;
double latS_deg = lat - dist_deg;
if (latN_deg >= 90 || latS_deg <= -90)
{//touches either pole
//we have special logic for longitude
double lonW_deg = -180, lonE_deg = 180;//world wrap: 360 deg
if (latN_deg <= 90 && latS_deg >= -90)
{//doesn't pass either pole: 180 deg
lonW_deg = lon - 90;
lonE_deg = lon + 90;
}
if (latN_deg > 90)
latN_deg = 90;
if (latS_deg < -90)
latS_deg = -90;
return ctx.MakeRect(lonW_deg, lonE_deg, latS_deg, latN_deg);
}
else
{
//--calc longitude bounds
double lon_delta_deg = CalcBoxByDistFromPt_deltaLonDEG(lat, lon, distance, radius);
double lonW_deg = lon - lon_delta_deg;
double lonE_deg = lon + lon_delta_deg;
return ctx.MakeRect(lonW_deg, lonE_deg, latS_deg, latN_deg);//ctx will normalize longitude
}
}
public override Point PointOnBearing(Point @from, double dist, double bearingDEG, SpatialContext ctx)
{
//TODO avoid unnecessary double[] intermediate object
if (dist == 0)
return from;
double[] latLon = DistanceUtils.PointOnBearingRAD(
DistanceUtils.ToRadians(from.GetY()), DistanceUtils.ToRadians(from.GetX()),
DistanceUtils.Dist2Radians(dist, ctx.GetUnits().EarthRadius()),
DistanceUtils.ToRadians(bearingDEG), null);
return ctx.MakePoint(DistanceUtils.ToDegrees(latLon[1]), DistanceUtils.ToDegrees(latLon[0]));
}
public void TestGeoCircle(SpatialContext ctx)
{
base.ctx = ctx;
//--Start with some static tests that once failed:
//Bug: numeric edge at pole, fails to init
ctx.MakeCircle(110, -12, ctx.GetDistCalc().DegreesToDistance(90 + 12));
//Bug: horizXAxis not in enclosing rectangle, assertion
ctx.MakeCircle(-44, 16, DegToDist(106));
ctx.MakeCircle(-36, -76, DegToDist(14));
ctx.MakeCircle(107, 82, DegToDist(172));
// TODO need to update this test to be valid
//{
// //Bug in which distance was being confused as being in the same coordinate system as x,y.
// double distDeltaToPole = 0.001;//1m
// double distDeltaToPoleDEG = ctx.getDistCalc().distanceToDegrees(distDeltaToPole);
// double dist = 1;//1km
// double distDEG = ctx.getDistCalc().distanceToDegrees(dist);
// Circle c = ctx.makeCircle(0, 90 - distDeltaToPoleDEG - distDEG, dist);
// Rectangle cBBox = c.getBoundingBox();
// Rectangle r = ctx.makeRect(cBBox.getMaxX() * 0.99, cBBox.getMaxX() + 1, c.getCenter().getY(), c.getCenter().getY());
// assertEquals(INTERSECTS, c.getBoundingBox().relate(r, ctx));
// assertEquals("dist != xy space", INTERSECTS, c.relate(r, ctx));//once failed here
//}
Assert.Equal(/*"nudge back circle", */ SpatialRelation.CONTAINS, ctx.MakeCircle(-150, -90, DegToDist(122)).Relate(ctx.MakeRect(0, -132, 32, 32), ctx));
Assert.Equal(/* "wrong estimate", */ SpatialRelation.DISJOINT, ctx.MakeCircle(-166, 59, 5226.2).Relate(ctx.MakeRect(36, 66, 23, 23), ctx));
Assert.Equal(/*"bad CONTAINS (dateline)",*/ SpatialRelation.INTERSECTS,
ctx.MakeCircle(56, -50, 12231.5).Relate(ctx.MakeRect(108, 26, 39, 48), ctx));
Assert.Equal(/*"bad CONTAINS (backwrap2)",*/ SpatialRelation.INTERSECTS,
ctx.MakeCircle(112, -3, DegToDist(91)).Relate(ctx.MakeRect(-163, 29, -38, 10), ctx));
Assert.Equal(/*"bad CONTAINS (r x-wrap)",*/ SpatialRelation.INTERSECTS,
ctx.MakeCircle(-139, 47, DegToDist(80)).Relate(ctx.MakeRect(-180, 180, -3, 12), ctx));
Assert.Equal(/*"bad CONTAINS (pwrap)",*/ SpatialRelation.INTERSECTS,
ctx.MakeCircle(-139, 47, DegToDist(80)).Relate(ctx.MakeRect(-180, 179, -3, 12), ctx));
Assert.Equal(/*"no-dist 1",*/ SpatialRelation.WITHIN,
ctx.MakeCircle(135, 21, 0).Relate(ctx.MakeRect(-103, -154, -47, 52), ctx));
Assert.Equal(/*"bbox <= >= -90 bug",*/ SpatialRelation.CONTAINS,
ctx.MakeCircle(-64, -84, DegToDist(124)).Relate(ctx.MakeRect(-96, 96, -10, -10), ctx));
//The horizontal axis line of a geo circle doesn't necessarily pass through c's ctr.
Assert.Equal(/*"c's horiz axis doesn't pass through ctr",*/ SpatialRelation.INTERSECTS,
ctx.MakeCircle(71, -44, DegToDist(40)).Relate(ctx.MakeRect(15, 27, -62, -34), ctx));
Assert.Equal(/*"pole boundary",*/ SpatialRelation.INTERSECTS,
ctx.MakeCircle(-100, -12, DegToDist(102)).Relate(ctx.MakeRect(143, 175, 4, 32), ctx));
Assert.Equal(/*"full circle assert",*/ SpatialRelation.CONTAINS,
ctx.MakeCircle(-64, 32, DegToDist(180)).Relate(ctx.MakeRect(47, 47, -14, 90), ctx));
//--Now proceed with systematic testing:
double distToOpposeSide = ctx.GetUnits().EarthRadius() * Math.PI;
Assert.Equal(ctx.GetWorldBounds(), ctx.MakeCircle(0, 0, distToOpposeSide).GetBoundingBox());
//assertEquals(ctx.makeCircle(0,0,distToOpposeSide/2 - 500).getBoundingBox());
double[] theXs = new double[] { -180, -45, 90 };
foreach (double x in theXs)
{
double[] theYs = new double[] { -90, -45, 0, 45, 90 };
foreach (double y in theYs)
{
TestCircle(x, y, 0);
TestCircle(x, y, 500);
TestCircle(x, y, DegToDist(90));
TestCircle(x, y, ctx.GetUnits().EarthRadius() * 6);
}
}
TestCircleIntersect();
}