Accept mouse clicks only on non-transparent pixels of an image (Views: 27)
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Problem/Question/Abstract: How to accept mouse clicks only on non-transparent pixels of an image Answer: Use a TImage descendant where you replace procedure TMouseImage.CMHitTest(var Msg: TWMMouse); begin inherited; if Assigned(PicUp) and Assigned(PicUp.Bitmap) and Transparent and (Msg.XPos < PicUp.Bitmap.Width) and (Msg.YPos < PicUp.Bitmap.Height) and (PicUp.Bitmap.Canvas.Pixels[Msg.XPos, Msg.YPos] = (Picture.Bitmap.TransparentColor and $FFFFFF)) then Msg.Result := 0; end; Now clicks on the control only work for non-transparent pixels even for holes in the picture. |