Non Transparent form art on transparent form

[joey o.]

Hi everyone,
I've been through all the info I can find in VB-World on transparent forms,but still come up short. I've got line art being drawn on my form.I want it to be transparent except for the line art so the user can change the background color using a form below it.Is this possible to do with vb?
If not how did they do it in paint? I tryed to iterate through the points to change the colors and it took over 5 minutes!
Any help is help.Thanks ahead of time.
Joey o.

[joey o.]

Forgot to add: When I use the form transparent code from vb-tips my line art is not a control so it disapears with the form.

[funkheads]

put the background picture on the form, but make the Form1.BackColor be great pink (255,0,255). then put this code is a .bas file:


Declare Function DeleteObject Lib "gdi32" (ByVal hObject As Long) As Long
Declare Function GetPixel Lib "gdi32" (ByVal hdc As Long, ByVal X As Long, ByVal Y As Long) As Long
Declare Function CreateRectRgn Lib "gdi32" (ByVal X1 As Long, ByVal Y1 As Long, ByVal X2 As Long, ByVal Y2 As Long) As Long
Declare Function SetWindowRgn Lib "user32" (ByVal hwnd As Long, ByVal hRgn As Long, ByVal bRedraw As Long) As Long
Declare Function CombineRgn Lib "gdi32" (ByVal hDestRgn As Long, ByVal hSrcRgn1 As Long, ByVal hSrcRgn2 As Long, ByVal nCombineMode As Long) As Long


Sub FormLoad(frm As Form)

Dim maskcolor As Long 'declare variable for the transparent color

'set transparent color as great pink
maskcolor = RGB(255, 0, 255)

'perform function to make windows transparent
TransBack 0, 0, frm.Width / 15, frm.Height / 15, maskcolor, frm.hdc, frm.hwnd

End Sub

Sub FormUnload()

DeleteObject rgn 'clean up before closing

End Sub

Private Sub TransBack(ByVal xstart As Long, ByVal ystart As Long, ByVal xend As Long, ByVal yend As Long, ByVal bgcolor As Long, ByVal thdc As Long, ByVal thWnd As Long)

'declare region variables
Dim rgn2 As Long, rgn3 As Long, rgn4 As Long

'declare substitute variables for the function parameters
Dim Top As Long, Left As Long, Right As Long, Bottom As Long, temptop As Long

'create some region buffers
rgn = CreateRectRgn(0, 0, 0, 0)
rgn2 = CreateRectRgn(0, 0, 0, 0)
rgn3 = CreateRectRgn(0, 0, 0, 0)

'this loop picks out the transparent colors,
'there MUST be three loops or Windows has a hard
'time handling the complex regions

Left = xstart
Right = (xend - xstart) + 1: Bottom = (yend - ystart) + 1

Do While Left < Right 'go through and scan left to right
Top = ystart
Do While Top < Bottom 'go through and scan top to botom
If GetPixel(thdc, Left, Top) <> bgcolor Then
temptop = Top
Do While GetPixel(thdc, Left, Top + 1) <> bgcolor
Top = Top + 1
If Top = Bottom Then Exit Do
Loop
rgn4 = CreateRectRgn(Left, temptop, Left + 1, Top + 1)
CombineRgn rgn3, rgn2, rgn2, 5
CombineRgn rgn2, rgn4, rgn3, 2
DeleteObject rgn4
End If
Top = Top + 1
Loop
CombineRgn rgn3, rgn, rgn, 5
CombineRgn rgn, rgn2, rgn3, 2
DoEvents
Left = Left + 1
Loop

DeleteObject rgn2
SetWindowRgn thWnd, rgn, True

End Sub


(obviously because it's what you're making ransparent) use a form for the next two proceedures.

in the Form_Load place this code:



FormLoad Me


when you unload the form, use the Form_Unload sub and put this code in there:

FormUnload


if you want to make a different color transparent other than Great Pink just chakge the maskcolor = RGB(###,###,###) to the color you want transparent, then make that the Form1.BackColor

[This message has been edited by funkheads (edited 12-06-1999).]

[joey o.]

I tested the above code by putting this into the mousemove event(among other things):

PSet (x, y), QBColor((Rnd * 7) + 8)

Then I put this code in the commandbutton_click event:

maskcolor = QBColor((Rnd * 7) + 8)
backcolor = maskcolor

It doesn't work for me. The drawing still goes away when the new color is selected.Am I doing something wrong? If anyone knows please help. I've been trying to make this work for quite some time now and I would like get on with my life.
thanks :(

[Frans C]

Try setting the forms AutoRedraw property to true.

[joey o.]

Tryed setting redraw to true - still no luck.

[funkheads]

the only thing i can think that might be wrong is that you are not keping in mind that the "maskcolor" has to be in RGB form (red 0-255, green 0-255, blue 0-255) in the format ###,###,###. that's all i can see that you are doing wrong. other than that i don't know how else to help you. sorry...

--michael

[joey o.]

Thanks for all the help so far!You've been great!I'll keep tryin'. Maybe I made a misprint or something simple.
Thanks again :)