According to MSDN:
Paints all descendants of a window in bottom-to-top painting order using double-buffering. Bottom-to-top painting order allows a descendent window to have translucency (alpha) and transparency (color-key) effects, but only if the descendent window also has the WS_EX_TRANSPARENT bit set. Double-buffering allows the window and its descendents to be painted without flicker. This cannot be used if the window has a class style of either CS_OWNDC or CS_CLASSDC.
Code: Select all
Gui, +E0x02000000 +E0x00080000 ; WS_EX_COMPOSITED & WS_EX_LAYERED => Double Buffer
Sample downloads attached.