The "2D" tools are only relevant when working with 2D frames. They will have no effect on the 3D windows.
They include:
This tool enables you to change the contrast and intensity of the GLI pixels. Since we are displaying images that often have 16 bits of grey values on screen that can only display 8 bits of color intensity, we need this tool to adjust how the grey levels are displayed.
This tool is used to change the current frame, change the current display mode or change the scaling of the selected frames.
This tool is used too modify the "Gamma" of the screen.
This tool enables you to display text overlays on top of the frames.