When you pan, SketchUp’s camera (your view) moves vertically or horizontally. This suspends the Orbit tool’s built-in sense of gravity, which keeps vertical edges pointed up and down.
Tip: You can temporarily activate the Orbit tool while in any other tool (except the Walk tool): In SketchUp, choosing this view aligns your perspective so that the view has two vanishing points. Two-Point Perspective: Illustrators often use two-point perspective to draw 3D buildings and concept art.Perspective: In this view, lines vanish to a horizon, so certain items appear closer while other items appear to be far away.When you print in this view, line length has a scale (for example 4’ in SketchUp = 1" on paper). This view is also known as an orthographic view. Parallel Projection: In this view, lines appear parallel in both 3D and 2D space.
SketchUp’s Camera menu also has three perspective options, shown in the following figure, that change how you view your model:
As you switch and modify your view, it’s as though you’re looking through a camera. Tip: When you use the standard views or the more advanced features of the navigation tools, remember that SketchUp uses the concept of a camera to represent your view.