For background see About the control toolbar.

 Using this tool, you can:Comments

Tilt the image up relative to its original position.

If you switch to the previous or next surface after tilting the image, the new tilt will still be in effect.

Tilt the image down relative to its original position.

Tilt the image right relative to its original position.

Tilt the image left relative to its original position.

Go to Window mode.

You can also press the spacebar to go to Window mode.