Scaling to Fit

The image of the model is drawn in a Graphic View in a specified orientation, at a specified scale, centred at a specified position. This section deals with scaling and positioning of the image, including zooming and panning.

Note that many operations that change the structure scale reproduce the display without regenerating the image. This can invalidate the reported scale for diagrams and contours. See Regenerating the image for more details.

A scale to fit involves an automatic adjustment of the scale, object point, mid-point and eye distance to result in the image fitting in the current view.

Scaling to fit occurs when any standard view is selected, when the Graphics | Orientation | Scale to fit (Ctrl+Home) menu command is given and when Do scale to fit is selected in the Graphic Settings dialog box. Scale to fit is also available on the Orientation toolbar.

First the extents of the image are determined. These are based on the undeformed state of the part of the model currently being drawn.

The object point is set to the centre of the extents.

The mid-point is set to 0,0,0 to result in the object point being drawn at the centre of the view.

A scale is calculated that will result in the extents, in their current orientation, fitting within the Auto-scale margin as set in the Graphics Preferences. The image is regenerated if the Regenerate graphics on standard view preference is set in the Graphics Preferences.

Scaling may be set to be to an engineering scale by toggling the Graphics | Orientation | Engineering Scale menu command and in the Graphic Settings dialog box. When set, the calculated scale is rounded up to the next engineering scale. If the view is an isometric view then it is the isometric scale that is set at an engineering scale.

An eye distance is arbitrarily set. This is five times a dimension of the image, where the dimension is the near extent to the far extent or, if that is zero, the left to right or the top to bottom.

The scale may be explicitly defined in the Graphic Settings dialog box. Note that when “Lock scale” is checked in this dialog box the specified scale is preserved when the window is resized and when the image is printed.