you must try to divive your game logic with your GUI code.
and you can use the signal/slot or event mode whith the notifycation between the game logc and GUI.
more techniquly. you can use scripte language such as lua, python to relate your game logic and GUI.
just follow one rude.
when you adjust your GUI. your wouldn't modify your game logic code.
which platform and API are you using. D3D.OPENGL etc.
have you opened the alpha test mode. and closed the alpha blend mode.
the when the bttmap tried to sample the value of a pixel. it will regard the value of you pic 's background.
especially your pic's background is whrite. and ou set it as alpha 0.
but when you tried to access it when your alpha blend mode is closed. you will get this result.