VBA & Classes - how to fill values?

[Rijnsent]

I'm trying to build some geographical classes in VBA. Am rather experienced in VBA, but do get stuck here. What I would like to do is set a geographical box, based on 2 coordinates (e.g. North Eastern point and South Western point). The coordinate-class is set up and works fine (named latLng), but I can't figure out how to set up the latLngBounds class. Can anyone here help me out?
Below are:

• my VBA test script
• the working latLng class
• the trouble maker latLngBounds class

Thanks in advance for some help/advice!

'TESTSCRIPT:
Sub TestBox()

Dim CoordSW As New latLng
CoordSW.lat = 52.067267
CoordSW.lon = 5.1114603
Dim CoordNE As New latLng
CoordNE.lat = 52.074799
CoordNE.lon = 5.1285214

Debug.Print CoordSW.toString
Debug.Print CoordSW.distanceTo(CoordNE)

Dim TotBox As New latLngBounds '? probably not the right way?
'Set TotBox.latLngBounds(CoordSW,CoordNE) '? same here?

End Sub

The working code for latLng:

' CLASS MODULE CODE for latLng
' following logic from https://leafletjs.com/reference-1.6.0.html#latlngbounds
' https://excelmacromastery.com/vba-class-modules/
'x = lon - East/West
'y = lat - North/South

' Member variable
Private clat As Double
Private clon As Double

' Properties
Property Get lat() As Double
    lat = clat
End Property
Property Let lat(value As Double)
    clat = value
End Property

Property Get lon() As Double
    lon = clon
End Property

Property Let lon(value As Double)
    clon = value
End Property

' Event - triggered when class created
Private Sub Class_Initialize()
    clat = 0
    clon = 0
End Sub

Public Function toString() As String
    'toString()  String Returns a string representation of the point (for debugging purposes).
    'e.g.  LatLng(51.504789, 5.046692)
    toString = "LatLng(" & Trim(Str(clat)) & "," & Str(clon) & ")"
End Function

Public Function distanceTo(latLngIn As latLng) As Double
    
    'distanceTo(<LatLng> otherLatLng) Number Returns the distance (in meters) to the given LatLng calculated using the Spherical Law of Cosines.
    'http://www.cpearson.com/excel/LatLong.aspx
    Dim Delta As Double
    Dim C_PI As Double
    C_PI = 4 * Atn(1)
    Dim C_RADIUS_EARTH_KM As Double
    C_RADIUS_EARTH_KM = 6370.97327862
    
    ' convert to radians: radians = (degrees/180) * PI
    Dim Lat1 As Double
    Dim Lat2 As Double
    Dim Long1 As Double
    Dim Long2 As Double
    Lat1 = (latLngIn.lat / 180) * C_PI
    Lat2 = (clat / 180) * C_PI
    Long1 = (latLngIn.lon / 180) * C_PI
    Long2 = (clon / 180) * C_PI
    
    Delta = ((2 * ArcSin(Sqr((Sin((Lat1 - Lat2) / 2) ^ 2) + Cos(Lat1) * Cos(Lat2) * (Sin((Long1 - Long2) / 2) ^ 2)))))
    distanceTo = 1000 * C_RADIUS_EARTH_KM * Delta

End Function

Private Function ArcSin(X As Double) As Double
    ' VBA doesn't have an ArcSin function. Improvise.
    ArcSin = Atn(X / Sqr(-X * X + 1))
End Function

And the trouble maker (effort so far):

' CLASS MODULE CODE for latLngBounds
' following logic from https://leafletjs.com/reference-1.6.0.html#latlngbounds
' https://excelmacromastery.com/vba-class-modules/

' Member variable
Private clatmax As Double
Private clonmax As Double
Private clatmin As Double
Private clonmin As Double

' Properties
Property Set latLngBounds(coord1 As latLng, coord2 As latLng)
    '? Is this the right way? Maybe should be a Let?
    If coord1.lat > coord2.lat Then
        clatmax = coord1.lat
        clatmin = coord2.lat
    Else
        clatmax = coord2.lat
        clatmin = coord1.lat
    End If

    If coord1.lon > coord2.lon Then
        clonmax = coord1.lon
        clonmin = coord2.lon
    Else
        clonmax = coord2.lon
        clonmin = coord1.lon
    End If

End Property

' Event - triggered when class created
Private Sub Class_Initialize()
    clatmin = 0
    clatmax = 0
    clonmin = 0
    clonmax = 0
End Sub

Public Function getCenter() As latLng
    'getCenter() LatLng
    'Returns the center point of the bounds.
    Dim CoordCenter As New latLng
    CoordCenter.lat = (clatmax + clatmin) / 2
    CoordCenter.lon = (clonmax + clonmin) / 2
    getCenter = CoordCenter
End Function

 

[bobsan42]

try to replace:

Property Set latLngBounds(coord1 As latLng, coord2 As latLng)

with:

Public Sub latLngBounds(coord1 As latLng, coord2 As latLng)

 

[Rijnsent]

Thanks, that does indeed work!
So I'd have to call my class by doing this?

Dim TotBox As New latLngBounds
Call TotBox.latLngBounds(CoordSW, CoordNE)

Mmm, I was hoping to have an object where I could do something like
Set TotBox.latLngBounds(CoordSW,CoordNE)
Is that possible with another syntax in my class (I'm assuming a Set)?

 

[bobsan42]

It is possible, but I wouldn't bother too much - once it works the way you want it - use it.
what exactly do you need an object for? TotBox the way you declared it is in general an object.
you can set it in another way but w/o much difference in this case:

Dim TotBox As latLngBounds
Set TotBox = New latLngBounds
Call TotBox.latLngBounds (CoordSW, CoordNE)

Actually another syntax you can use without CALL is:

TotBox.latLngBounds CoordSW, CoordNE

 

[Rijnsent]

Okay, you're right... If it works, don't break it. Thanks for the feedback!
P.S. I like your avatar, cute dog

 

[bobsan42]