AutoHotkey Community

Truth be told, this trick is ridiculously easy to pull off. To make a form "click-through", all you need to do is:

1. Grab the current value of the Extended Style attributes for the window you want to be invisible to the mouse. This requires a call to the Win32 API function GetWindowLong(hWnd, nIndex). The two parameters are as follows:
* hWnd - The handle to the window we want to get the attributes for
* nIndex - The zero-based offset to the value to be retrieved. In our case, GWL_EXSTYLE, or -20
2. Modify the value returned by GetWindowLong() and turn on the bits you want. This is done using a bit-wise OR operation. We want to turn on the bits specified by WS_EX_LAYERED and WS_EX_TRANSPARENT.

newValue = oldValue Or WS_EX_LAYERED Or WS_EX_TRANSPARENT

3. Write the new value back to the window by calling SetWindowLong(hWnd, nIndex, dwNewLong). The first two are exactly the same as the call to GetWindowLong(). The third is, obviously, the new value we want written to the window.
4. Now that the window is a Layered Window, we have to modify another attribute of the form, the Alpha attribute. If this is not done, the default value for Alpha will be 0, or visibly transparent, and we won't see our form at all! This is accomplished with a call to SetLayeredWindowAttributes(hWnd, crKey, bAlpha, dfFlags).
* hWnd - The handle to the window we want to set the attribute for
* crRef - Specifies a transparency color key. All pixels with this color in the form will be transparent
* bAlpha - Specifies the opacity of the window, 0 (transparent) through 255 (opaque)
* dwFlags - Specifies an action to take
* LWA_COLORKEY - Uses crKey as the transparency color
* LWA_ALPHA - Uses bAlpha to determine the opacity of the window

anyone know how I can do this in autohotkey? I don't have any experience with dll calls and such.