Zoom Controls

autoscale: this button zooms into your structure to make it as big as it can, but still fitting int the frame

zoom out: this button zooms out so that your structure is about 1/3 of the frame size

box zoom (faded): to enable this button, click the left mouse button somewhere on the grid and drag to create a box. The box zoom button is now enabled and if you click on it, it zooms into whatever you have boxed.