🚀 go-pugleaf

VB snippet below which scales an image to a dimension of 800 (pixels) if either dimension is >800 and it maintains the aspect ratio. Don't know if this is what you are looking for but it might help somebody.
formImage.Width and formImage.Height are the original dimensions.

Dim height, width, aspectRatio, reductionFactor As Double

aspectRatio = formImage.Width / formImage.Height
height = formImage.Height
width = formImage.Width

If aspectRatio >= 1 Then
            If width > 800 Then
                width = 800
                reductionFactor = 800 / formImage.Width
                height = formImage.Height * reductionFactor
            End If
Else
            If height > 800 Then
                height = 800
                reductionFactor = 800 / formImage.Height
                width = formImage.Width * reductionFactor
            End If
End If