Help! Get color of pixel at location "X, Y"

[parksie]

Hang on, you mean:

Check if the specific screen pixel is a certain colour, and if so, simulate a click event on it?

You need some API for this. What to do: WindowFromPoint will return the window handle. Then, offset the point into coordinates for that window. Then, get the colour using GetPixel. Compare that, and if so, simulate a click at that position, using SendMessage and WM_CLICK. If you need an example I'll post it here.

is this what you mean?

Private Declare Function GetPixel Lib "gdi32" (ByVal hdc As Long, ByVal X As Long, ByVal Y As Long) As Long

Private Declare Function SetPixel Lib "gdi32" (ByVal hdc As Long, ByVal X As Long, ByVal Y As Long, ByVal crColor As Long) As Long

Private Sub Command1_Click()
For X = 0 To Picture1.Width
  For Y = 0 To Picture1.Height
    If GetPixel(Picture1.hdc, X, Y) = vbRed Then
      Call SetPixel(Picture1.hdc, X, Y, vbYellow)
    End If
  Next
Next
End Sub

[candycrazie]

parksie: You've got what I'm looking for there. Could you please post that example? Thanks a lot

[parksie]

will post tomorrow as my isp is about to disconnect me.

[kedaman]

I would like to differ from parksies suggestion,

1. You Get the desktopwindow's DC, with getwindowDc and getdesktopwindow
2. Get the color with getpixel
3. Use mouseevent to click

[kedaman]

Ok, i put this together

'In a module
Declare Sub mouse_event Lib "user32" (ByVal dwFlags As Long, ByVal dx As Long, ByVal dy As Long, ByVal cButtons As Long, ByVal dwExtraInfo As Long)
Declare Function GetWindowDC Lib "user32" (ByVal hwnd As Long) As Long
Declare Function GetDesktopWindow Lib "user32" () As Long
Declare Function GetPixel Lib "gdi32" (ByVal hdc As Long, ByVal x As Long, ByVal y As Long) As Long
Declare Function SetCursorPos Lib "user32" (ByVal x As Long, ByVal y As Long) As Long

Sub OnColorClick(x As Long, y As Long, matchcolor As Long)
    If GetPixel(GetWindowDC(GetDesktopWindow), x, y) = matchcolor Then
        SetCursorPos x, y
         mouse_event 2, 0, 0, 0, 0
         mouse_event 4, 0, 0, 0, 0
    End If
End Sub

'In code (for instance)

OnColorClick 50, 100, vbYellow

Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Private Declare Function GetPixel Lib "gdi32" (ByVal hdc As Long, ByVal x As Long, ByVal y As Long) As Long
Private Declare Function GetCursorPos Lib "user32" (lpPoint As POINTAPI) As Long
Private Declare Sub mouse_event Lib "user32" (ByVal dwFlags As Long, ByVal dx As Long, ByVal dy As Long, ByVal cButtons As Long, ByVal dwExtraInfo As Long)
Private Declare Function GetDesktopWindow Lib "user32" () As Long
Private Declare Function GetWindowDC Lib "user32" (ByVal hwnd As Long) As Long

Private Const MOUSEEVENTF_LEFTDOWN = &H2 '  left button down
Private Const MOUSEEVENTF_LEFTUP = &H4 '  left button up

Private Type POINTAPI
        x As Long
        y As Long
End Type

Dim ThePoint As POINTAPI
Dim TheHwnd As Long
Dim TheDC As Long
Dim TheColor As Long




Private Sub Form_Load()
  
  Timer1.Interval = 25
  Timer2.Interval = 100

End Sub

Private Sub Timer1_Timer()

  Call GetCursorPos(ThePoint)

  TheHwnd = GetDesktopWindow
  TheDC = GetWindowDC(TheHwnd)
  TheColor = GetPixel(TheDC, ThePoint.x, ThePoint.y)

  If TheColor = 12632256 Then
    Call mouse_event(MOUSEEVENTF_LEFTDOWN, ThePoint.x, ThePoint.y, 0, 0)
    Call mouse_event(MOUSEEVENTF_LEFTUP, ThePoint.x, ThePoint.y, 0, 0)
  End If

End Sub

Private Sub Timer2_Timer()

  Timer1.Enabled = True

End Sub

the second Timer is needed because it seems that timer1 keeps disabling itself.

[candycrazie]

denniswrenn: THAT was just what I was looking for, thanks a MILLION!!!

I am glad to be of help to you

oh incase you havent noticed, I have a SendMessage declaration in there, you can remove it, I just forgot to after I finished with it(I was trying to use that instead of mouse_event(BTW: Thanks kedaman!)).