ClemensFischer/XAML-Map-Control
1
0
Fork 0
mirror of https://github.com/ClemensFischer/XAML-Map-Control.git synced 2026-04-08 16:05:50 +00:00
Code Issues Projects Releases Packages Wiki Activity

Fixed RelativeTransform of azimuthal projections

Browse source
This commit is contained in:
ClemensFischer 2026-01-28 09:52:11 +01:00
parent 8d25310b8e
commit 3922297e7b
12 changed files with 72 additions and 39 deletions
Download patch file Download diff file Expand all files Collapse all files

7
MapControl/Shared/TransverseMercatorProjection.cs
View file

@ -68,6 +68,7 @@ namespace MapControl
// λ - λ0
var dLambda = (longitude - CentralMeridian) * Math.PI / 180d;
var cosLambda = Math.Cos(dLambda);
var tanLambda = Math.Tan(dLambda);
// t
var t = Math.Sinh(Atanh(sinPhi) - f2 * Atanh(f2 * sinPhi));
var u = Math.Sqrt(1d + t * t);
@ -88,14 +89,12 @@ namespace MapControl
var n = Flattening / (2d - Flattening);
var m = (1d - n) / (1d + n) * Math.Tan(phi);
// h = k/k0 for relative scale
var h = f1 * Math.Sqrt((1d + m * m) * (sigma * sigma + tau * tau) / (t * t + cosLambda * cosLambda));
var k = ScaleFactor * f1 * Math.Sqrt((1d + m * m) * (sigma * sigma + tau * tau) / (t * t + cosLambda * cosLambda));
var tanLambda = Math.Tan(dLambda);
// γ, meridian convergence angle
var gamma = Math.Atan2(tau * u + sigma * t * tanLambda, sigma * u - tau * t * tanLambda);
var transform = new Matrix(h, 0d, 0d, h, 0d, 0d);
var transform = new Matrix(k, 0d, 0d, k, 0d, 0d);
transform.Rotate(-gamma * 180d / Math.PI);
return transform;