The zoom command adjusts the apparent size of viewed items by factor relative to the current display. The factor must be positive:
The change is spread out over a specified number of image update frames N (default 1). The apparent size is multiplied by an equal value at each frame as needed to achieve the final result.
Alternatively or in addition to factor, the pixelSize option can be used to specify the absolute scale in length per pixel at the current center of rotation (in data coordinate units, typically Å). The depth of this point matters when perspective is used, because nearby objects appear larger than faraway objects. A constant pixel size is useful for making multiple images at the same scale. If factor is also given, it is applied after the pixel size to calculate the overall (final) amount of zoom.
Given without argments, zoom reports the absolute scale at the current center of rotation.
Zooming moves the camera toward or away from the scene. It does not change model coordinates.
See also: view, camera, mousemode, Side View, making movies