Rewrote main.cpp to make more sense, when selecting windows with slop: maim will now single the window out and screenshot it separately from the screen, fixed a bug when using negative position values that would position the screenshot wrong. For whatever reason gnome-terminal gets a 10pixel thick black border around it when selected as a window to screenshot, not sure how to fix it besides masking the window (which would remove pretty shadows from other windows). So I didn't mask it. Make an issue if you have trouble selecting windows now.