Formula To VBA Help (Burnt out on a Monday!)

[BlueIshDan]

Here it goes. I'm working with multiple coordinate systems with ouR engineering data here at work. I need to select an area in an outer scope grid (Main grid) and get the x, y values in the sub coordinate systems.

I have the formula I just can't wake up enough to get it right in my code.
If anyone could help figure this out with me I'd be SO grateful!

Here is what the Formula is.

Here is what my code is as of now. Don't mind the variants I just haven't seen the behaviour of the numbers yet, it will be done properly later on.

Option Explicit

Const MAIN_MAX_X As Integer = 11600
Const MAIN_MAX_Y As Integer = 10000

Private Sub rectCoordinateScope_MouseMove(Button As Integer, Shift As Integer, x As Single, Y As Single)
    
    Dim x_percent As Variant: x_percent = Round(x / rectCoordinateScope.Width, 2)
    Dim y_percent As Variant: y_percent = Round(Y / rectCoordinateScope.Height, 2)
    
    lblMainX.Caption = MAIN_MAX_X * x_percent
    lblMainY.Caption = MAIN_MAX_Y * y_percent
    
    txtSouthGridX.Value = ConvertX(1, 0, CLng(lblMainX.Caption), CLng(lblMainY.Caption), 2000)
    txtSouthGridY.Value = ConvertY(1, 0, CLng(lblMainX.Caption), CLng(lblMainY.Caption), 2000)
    
End Sub

Public Function ConvertX(ByVal coordinate_scale As Variant, _
                         ByVal rotation As Variant, _
                         ByVal from_x As Variant, _
                         ByVal from_y As Variant, _
                         ByVal translation_x As Variant) As Variant
                         
    ConvertX = Sqr(coordinate_scale * (from_x * Cos(0) - from_y * Sin(0)) + translation_x)
    
End Function

Public Function ConvertY(ByVal coordinate_scale As Variant, _
                         ByVal rotation As Variant, _
                         ByVal from_x As Variant, _
                         ByVal from_y As Variant, _
                         ByVal translation_y As Variant) As Variant
                         
    ConvertY = Sqr(coordinate_scale * (from_x * Cos(0) + from_y * Sin(0)) + translation_y)
    
End Function

 

[vbaInet]

You'll need a Maths genius who understands your formula to help you with this one Which I'm not

Anyway, it's seems apparent what your calculations are there. Although the compiler should do the multiplications first additions and subtractions follow, I would be inclined to bracket properly. I'll take the first one (i.e. ConvertX) as an example:

ConvertX = Sqr((coordinate_scale * ((from_x * Cos(0)) - (from_y * Sin(0)))) + translation_x)

Always good to put those extra brackets. Compare the result of that to what you had before.

 

[vbaInet]

And another thing, are you sure you should be casting those captions to Long instead of Decimal or Double?

 

[BlueIshDan]

Thank you very much for your reply vbaInet!
Yes, It was converted into whole numbers.

 

[BlueIshDan]

Blah, just learned that the SouthGrid Coordinate System is used as the base coordinate system here -.-

Undocumented of course.

 

[vbaInet]

Blah, just learned that the SouthGrid Coordinate System is used as the base coordinate system here -.-

Undocumented of course.

What does this mean for you?

 

[BlueIshDan]

The main scope was just an imaginary grid that I made.
I made that grid to place the 3 sub grid systems into.

From what I know now. There is no containing grid system. The 3 systems are relative to each other. Here is a chart I found in documentation.

 

[vbaInet]

I'm not following. Of course you understand this stuff more than myself, so if you can explain in layman's terms that would be great

How does this new find affect your code?

 

[BlueIshDan]

Well, what the formula does is converts one coordinates systems x,y to another's.

My initial thought was that the three coordinate systems were all contained in one large grid. Then I came to realize that they're not and they all just relate to each other.

This will not affect the code, It will simply affect the results .

 

[vbaInet]

Meaning you didn't need to do the conversion in the first place?

 

[BlueIshDan]

No meaning I was converting using the wrong values. I have yet to test this new understanding. Got into something at work lol. No more exploring time for now

 

[vbaInet]

Let me know how it pans out.

 

[BlueIshDan]

edited to move to new thread since this one is dead.

 

[pr2-eugin]

I would approve !

EDIT: Burn out Wednesday ! Lol

 

[BlueIshDan]

Just realized I had forgot to invert the Cos and Sin when converting the Y value.
Also relized I was putting 0 into the Cos and Sin instead of the rotation.
(burnt out week I guess)

 

[vbaInet]

I thought you were representing theta as zero. Obviously not then.