Logic check and/or better way?

Hate to be paranoid, but....

I wrote a function that takes the height and width of a full size, uploaded image and returns - allegedly, It seems to anyway - new dimensions with the aspect ratio preserved.

My function seems awkward. Could anyone suggest a better approach?
Thanks!

VB Code:

Function RetainAspectRatio(ByVal imgHeight As Integer, ByVal imgWidth As Integer, ByVal IsItASmallThumb As Boolean) As ArrayList
        Dim blnSizeCheck As Boolean = IsItASmallThumb
        Dim maxheight As Integer
        Dim maxwidth As Integer
        If blnSizeCheck Then
            maxheight = 93
            maxwidth = 125
        Else
            maxheight = 300
            maxwidth = 400
        End If
        imgHeight = Convert.ToDouble(imgHeight)
        imgWidth = Convert.ToDouble(imgWidth)
        'Get the new height and width depending on whether the end result will be a small thumb or medium-size image
        'image
        If (imgWidth > imgHeight) Or (imgWidth = imgHeight) Then
            While imgWidth > maxwidth
                imgWidth = Math.Round(imgWidth - (imgWidth * 0.01), 0)
                imgHeight = Math.Round(imgHeight - (imgHeight * 0.01), 0)
            End While
        ElseIf imgHeight > imgWidth Then
            While (imgHeight > maxheight) Or (imgWidth > maxwidth)
                imgWidth = Math.Round(imgWidth - (imgWidth * 0.01), 0)
                imgHeight = Math.Round(imgHeight - (imgHeight * 0.01), 0)
            End While
        End If
        'send the new dimensions back in an arraylist
        imgWidth = Convert.ToInt32(imgWidth)
        imgHeight = Convert.ToInt32(imgHeight)
        Dim arDimensions As New ArrayList
        arDimensions.Add(imgWidth)
        arDimensions.Add(imgHeight)
        Return arDimensions
    End Function

Well I don't see a reason to dim blnSizeCheck, just use IsItASmallThumb.
Also your converting the height and width to a double and the sticking it back into an integer which converts it straight back to an integer again...
Is there a reason your using an arraylist? You could just use a string array like this;

Code:

---

Dim arDimensions(1) As string = {imgWidth, imgHeight}

---

I just noticed you also rounding when you subtract 1% which would make using a double pointless anyway. Looking at your if's and while's again I also realized you only really need the second one 'While (imgHeight > maxheight) Or (imgWidth > maxwidth)' as both need to resolve too true before it'll exit the loop and thus will keep scaling down untill both are withing the size limit

ug that is not the way to do it (if I get what you are trying to do)

I dont have time to test this code but you need to work out the second dimension (depending on if height>width or width>height) based on a scale factor

Code:

---

  dim scale as double
  If (imgWidth >= imgHeight) Then
      'need to calculate the percent of the width to maxwidth
      scale= maxwidth/imgwidth
    Else  ' If imgHeight > imgWidth Then (dont need the logic check)
        scale= maxheight/imgHeight
  end if
  imgWidth = imgwidth * scale '(or imgwidth *= scale)
  imgHeight = imgheight * scale

---

Summat like that anyway.

also this line:
If (imgWidth > imgHeight) Or (imgWidth = imgHeight) Then
is the same as:
If (imgWidth >= imgHeight) Then


Hope that helps

GaZ

Guys

Sorry - been out, but thank you for your replies. I sniffed around, and ended up with this

VB Code:

If imgWidth > maxwidth Or imgHeight > maxheight Then
            If (maxheight / imgHeight) > (maxwidth / imgWidth) Then
                scale = maxheight / imgHeight
            Else
                scale = maxwidth / imgWidth
            End If
            If imgWidth > maxwidth Then
                scale = maxwidth / imgWidth
                imgWidth *= scale
                imgHeight *= scale
            End If
            If imgHeight > maxheight Then
                imgWidth /= scale
                imgHeight /= scale
                scalefactor = maxheight / imgHeight
                imgWidth *= scale
                imgHeight *= scale
            End If
        End If

TPM - right, dumped the arraylist. Kept the boolean. This generates dimensions for one of 2 sizes of saved images, depending on the T or F.

Thanks again :)

Dawg