XL 2016 VBA - Déterminer la pente de la Forme ligne ou flèche ou mieux son équation

Sub BTFLIPV_Cliquer()
    ActiveSheet.Shapes("ligne").Flip msoFlipVertical
End Sub
Sub BTFLIPH_Cliquer()
    ActiveSheet.Shapes("ligne").Flip msoFlipHorizontal
End Sub

Sub BTGO_Cliquer()
    CalculerDiagonaleRectangle2
End Sub

Sub CalculerDiagonaleRectangle2()
    On Error Resume Next
    ActiveSheet.Shapes("controleur").Delete
    On Error GoTo 0

    Dim Lg#, HT, Diagonale#, DiffWidth, L1#, L2


    Set SHAP = ActiveSheet.Shapes("ligne")
    Set shap2 = ActiveSheet.Shapes("rectrouge")

    'données de base
    Lg = SHAP.Width                 'largeur
    HT = SHAP.Height                'hauteur
    tp = SHAP.Top                   'top
    bottom = SHAP.Top + SHAP.Height    'bottom

    'Diagonale = Sqr(Ht ^ 2 + Lg ^ 2)'méthode math abrogée

    newtp = shap2.Top
    newht = bottom - newtp
    newlg = Lg / (HT / newht)    'reduit la largeur  au même ratio que la reduction du height
    DiffWidth = Abs(Lg - newlg)

    'MsgBox HT & vbCrLf & Lg & vbCrLf & vbCrLf & newht & vbCrLf & newlg

    'visuel de l'intersection des deux rectangles en ajoutant un rectangle vide borduré
    Set Shp = ActiveSheet.Shapes.AddShape(1, SHAP.Left, bottom - newht, newlg, newht)
    Shp.Name = "controleur"
    Shp.Fill.Visible = False
    Shp.Line.ForeColor.RGB = vbGreen




    With shap2
        L1 = SHAP.Left + newlg - (shap2.Width / 2)
        L2 = SHAP.Left + DiffWidth - (shap2.Width / 2)
        If SHAP.VerticalFlip Then
            If SHAP.HorizontalFlip Then .Left = L2 Else .Left = L1
            If SHAP.HorizontalFlip Then Shp.Left = SHAP.Left + SHAP.Width - Shp.Width Else Shp.Left = SHAP.Left
        Else
            If SHAP.HorizontalFlip Then .Left = L1 Else .Left = L2
            Shp.Left = SHAP.Left + DiffWidth
            If SHAP.HorizontalFlip Then Shp.Left = SHAP.Left Else Shp.Left = SHAP.Left + SHAP.Width - Shp.Width

        End If

    End With
End Sub

Option Explicit
Function GetDiagonalPositionLeft(SHAP, SHAP2) As Double
'*****************************************
'Reposition in terms of left a shape(1) at the intersection of another shape(2) of type "MsoLine" according to the top of the shapes(1)
'Version coded by patricktoulon
'Version1 1.0
'Date version:08/04/2024
'Request from @Dudu2 in a discussion on ExcelDownloads
'https://excel-downloads.com/threads/vba-determiner-la-pente-de-la-forme-ligne-ou-fleche-ou-mieux-son-equation.20082379/page-2#posts
'*****************************************
    Dim Lg#, HT#, Tp#, NewTp#, NewLg#, NewHt, Bottom#, DiffWidth, L1#, L2, LF#

    'Position data and size of the shapes (SHAP2 = "LINE")
    Lg = SHAP.Width                 'Width of shape (MsoLine)
    HT = SHAP.Height                'Height of shape (MsoLine)
    Tp = SHAP.Top                   'Top of shape (MsoLine)
    Bottom = SHAP.Top + SHAP.Height 'Bottom of shape (MsoLine)

    NewTp = SHAP2.Top               'Width of  shape(Msoline or MsoArrow
    NewHt = Bottom - NewTp          'Height of intersection rectangle
    NewLg = Lg / (HT / NewHt)       'Reducing the width of the rectangle to the same ratio as reducing its height

    DiffWidth = Abs(Lg - NewLg)     'Difference in width of the two occupation rectangles

    'Two possibilities of left according to the vertical and horizontal flip rotation
    L1 = SHAP.Left + NewLg - (SHAP2.Width / 2)
    L2 = SHAP.Left + DiffWidth - (SHAP2.Width / 2)

    'Selection of one of the two possibilities depending on the flip
    If SHAP.VerticalFlip Then
        If SHAP.HorizontalFlip Then LF = L2 Else LF = L1
    Else
        If SHAP.HorizontalFlip Then LF = L1 Else LF = L2
    End If
    GetDiagonalPositionLeft = LF
End Function


Sub applique() 'SUB DE TEST
    Dim X#
    With ActiveSheet
        X = GetDiagonalPositionLeft(.Shapes("ligne"), .Shapes("rectrouge"))
        .Shapes("rectrouge").Left = X
    End With
End Sub

If (.VerticalFlip = msoTrue And .HorizontalFlip = msoFalse) Or (.VerticalFlip = msoFalse And .HorizontalFlip = msoTrue)

If .VerticalFlip + .HorizontalFlip = 1