/// <summary>
/// Changes the Center, Heading and ZoomLevel properties according to the specified
/// viewport coordinate translation, rotation and scale delta values. Rotation and scaling
/// is performed relative to the specified center point in viewport coordinates.
/// </summary>
public void TransformMap(Point center, Vector translation, double rotation, double scale)
{
if (rotation != 0d || scale != 1d)
{
transformCenter = MapProjection.ViewportPointToLocation(center);
viewportCenter = center + translation;
if (rotation != 0d)
{
var heading = (((Heading + rotation) % 360d) + 360d) % 360d;
SetValueInternal(HeadingProperty, heading);
SetValueInternal(TargetHeadingProperty, heading);
}
if (scale != 1d)
{
var zoomLevel = Math.Min(Math.Max(ZoomLevel + Math.Log(scale, 2d), MinZoomLevel), MaxZoomLevel);
SetValueInternal(ZoomLevelProperty, zoomLevel);
SetValueInternal(TargetZoomLevelProperty, zoomLevel);
}
UpdateTransform(true);
}
else
{
TranslateMap(translation); // more precise
}
}
/// <summary>
/// Changes the Center property according to the specified translation in viewport coordinates.
/// </summary>
public void TranslateMap(Vector translation)
{
if (transformCenter != null)
{
ResetTransformCenter();
UpdateTransform();
}
if (translation.X != 0d || translation.Y != 0d)
{
Center = MapProjection.ViewportPointToLocation(viewportCenter - translation);
}
}
/// <summary>
/// Sets a temporary center point in viewport coordinates for scaling and rotation transformations.
/// This center point is automatically reset when the Center property is set by application code.
/// </summary>
public void SetTransformCenter(Point center)
{
transformCenter = MapProjection.ViewportPointToLocation(center);
viewportCenter = center;
}
/// <summary>
/// Transforms a Point in viewport coordinates to a Location in geographic coordinates.
/// </summary>
public Location ViewportPointToLocation(Point point)
{
return(MapProjection.ViewportPointToLocation(point));
}
