private void UpdateInternals()
{
// FIXME: the half map scale is a value used throughout the implementation to rule the camera elevation
// and the size/scale of the tiles, it depends on fixed tile size and resolution (here 256 and 72) so I am not
// sure it would work for a tile layer with different values...
// maybe there is a way to take the values out of the calculations and reintroduce them on Layer level...
// FIXME: the 'division by 20000' helps the values to be kept in range for the Unity3D engine, not sure
// this is the right approach either, feels kinda voodooish...
halfMapScale = GeoHelpers.OsmZoomLevelToMapScale(currentZoom, /*(float)centerWGS84[1]*/ 0.0f, tileResolution, 72) / scaleDivider;
roundedHalfMapScale = GeoHelpers.OsmZoomLevelToMapScale(roundedZoom, (float)/*(float)centerWGS84[1]*/ 0.0f, tileResolution, 72) / scaleDivider;
metersPerPixel = GeoHelpers.MetersPerPixel(0.0f, (float)currentZoom);
roundedMetersPerPixel = GeoHelpers.MetersPerPixel(0.0f, (float)roundedZoom);
// FIXME: another voodoish value to help converting meters (EPSG 900913) to Unity3D world coordinates
scaleMultiplier = halfMapScale / (metersPerPixel * tileResolution);
roundedScaleMultiplier = roundedHalfMapScale / (roundedMetersPerPixel * tileResolution);
}
// <summary>
// Zooms the map.
// </summary>
public void Zoom(float zoomSpeed)
{
// apply the zoom
CurrentZoom += 4.0f * zoomSpeed * Time.deltaTime;
// move the camera
// FIXME: the camera jumps on the first zoom when tilted, 'cause cam altitude and zoom value are unsynced by the rotation
Transform cameraTransform = currentCamera.transform;
float y = GeoHelpers.OsmZoomLevelToMapScale(currentZoom, 0.0f, tileResolution, 72) / scaleDivider * screenScale;
float t = y / cameraTransform.forward.y;
cameraTransform.position = new Vector3(
t * cameraTransform.forward.x,
y,
t * cameraTransform.forward.z);
// set the update flag to tell the behaviour the user is manipulating the map
hasMoved = true;
IsDirty = true;
}