Adjust to different monitors/Display resolutions?

I want my application to change size of forms and various controls to accomodate different monitors and different resolutions for the same monitor. I am doing some point plotting, using ScaleMode 7 (Centimeters) for a Picture Box (where I plot points) and ScaleMode 1 (Twips) elsewhere.

Any advice, hints, citations, etcetera would be appreciated.

I am working with VB6. I have Visual Studio & MSDN Library.

First, are above Scale Modes reasonable for my purposes? They seem to work okay, but I have yet to add logic for Display changes.

MSDN shows sample code using Sysinfo1_Displaychanged Event. Example uses Screen.TwipsPerPixelX to decide how to size controls. For my System, TwipsPerPixelX does not change when I change from 640X480 to 1024X768. An experiment suggests that Sysinfo1.WorkAreaWidth changes. Does ScaleMode setting affect these variables?

What affects TwipsPerPixel? How do I check for Display Resolution? How do I detect a Monitor with a different Dot Pitch? Should I worry about Dot Pitch?

Any clues you can give me about Twips, Pixels, Scale Mode, Screen sizes, et cetera would be appreciated.

Thanx

' #VBIDEUtils#************************************************************
' * Programmer Name : Mikhail Shmukler
' * Web Site : http://www.geocities.com/ResearchTriangle/6311/
' * E-Mail : [email protected]
' * Date : 13/10/98
' * Time : 10:24
' * Module Name : class_Elastic
' * Module Filename : Elastic.cls
' **********************************************************************
' * Comments :
' * This class can change size and location of controls On your form
' * 1. Resize form
' * 2. Change screen resolution
' * Assumes:1. Add Elastic.cls
' * 2. Add declaration 'Private El as New class_Elastic'
' * 3. Insert string like 'El.init Me' (formload event)
' * 4. Insert string like 'El.FormResize Me' (Resize event)
' * 5. Press 'F5' and resize form ....
'
'****************************************************************

Option Explicit
Private nFormHeight As Integer
Private nFormWidth As Integer
Private nNumOfControls As Integer
Private nTop() As Integer
Private nLeft() As Integer
Private nHeight() As Integer
Private nWidth() As Integer
Private nFontSize() As Integer
Private nRightMargin() As Integer
Private bFirstTime As Boolean

Sub Init(frm As Form, Optional nWindState As Variant)

Dim I As Integer
Dim bWinMax As Boolean

bWinMax = Not IsMissing(nWindState)

nFormHeight = frm.Height
nFormWidth = frm.Width
nNumOfControls = frm.Controls.Count - 1
bFirstTime = True
ReDim nTop(nNumOfControls)
ReDim nLeft(nNumOfControls)
ReDim nHeight(nNumOfControls)
ReDim nWidth(nNumOfControls)
ReDim nFontSize(nNumOfControls)

ReDim nRightMargin(nNumOfControls)
On Error Resume Next
For I = 0 To nNumOfControls
If TypeOf frm.Controls(I) Is Line Then
nTop(I) = frm.Controls(I).Y1
nLeft(I) = frm.Controls(I).X1
nHeight(I) = frm.Controls(I).Y2
nWidth(I) = frm.Controls(I).X2
Else
nTop(I) = frm.Controls(I).Top
nLeft(I) = frm.Controls(I).Left
nHeight(I) = frm.Controls(I).Height
nWidth(I) = frm.Controls(I).Width
nFontSize(I) = frm.FontSize
nRightMargin(I) = frm.Controls(I).RightMargin
End If
Next

If bWinMax Or frm.WindowState = 2 Then ' maxim
frm.Height = Screen.Height
frm.Width = Screen.Width
Else
frm.Height = frm.Height * Screen.Height / 7290
frm.Width = frm.Width * Screen.Width / 9690
End If

bFirstTime = True

End Sub

Sub FormResize(frm As Form)

Dim I As Integer
Dim nCaptionSize As Integer
Dim dRatioX As Double
Dim dRatioY As Double
Dim nSaveRedraw As Long

On Error Resume Next
nSaveRedraw = frm.AutoRedraw

frm.AutoRedraw = True

If bFirstTime Then
bFirstTime = False
Exit Sub
End If

If frm.Height < nFormHeight / 2 Then frm.Height = nFormHeight / 2

If frm.Width < nFormWidth / 2 Then frm.Width = nFormWidth / 2
nCaptionSize = 400
dRatioY = 1# * (nFormHeight - nCaptionSize) / (frm.Height - nCaptionSize)
dRatioX = 1# * nFormWidth / frm.Width
On Error Resume Next ' for comboboxes, timeres and other nonsizible controls

For I = 0 To nNumOfControls
If TypeOf frm.Controls(I) Is Line Then
frm.Controls(I).Y1 = Int(nTop(I) / dRatioY)
frm.Controls(I).X1 = Int(nLeft(I) / dRatioX)
frm.Controls(I).Y2 = Int(nHeight(I) / dRatioY)
frm.Controls(I).X2 = Int(nWidth(I) / dRatioX)
Else
frm.Controls(I).Top = Int(nTop(I) / dRatioY)
frm.Controls(I).Left = Int(nLeft(I) / dRatioX)
frm.Controls(I).Height = Int(nHeight(I) / dRatioY)
frm.Controls(I).Width = Int(nWidth(I) / dRatioX)
frm.Controls(I).FontSize = Int(nFontSize(I) / dRatioX) + Int(nFontSize(I) / dRatioX) Mod 2
frm.Controls(I).RightMargin = Int(nRightMargin(I) / dRatioY)
End If
Next

frm.AutoRedraw = nSaveRedraw

End Sub