Symbology Size Units

Size units are indications of how dimensions are measured and, more importantly, how they react to a change of scale when the entities to which they apply are modified.

Possible size unit values are as follows:

Value	Meaning
A	Actual millimeters as seen
M or W	Modeling (aka world) units
P	Screen pixels
R	Real world meters
T	Screen points

Command switches and function parameters which take a size units value accept one of the above case-insensitive single characters as a string value, e.g.

markerstyle mystyle,-su='A'

To explain the difference between the various values, assume we have a dimension of 10 and the size units values would then have the following visual effects:

Value	Description
A	The dimension will always be displayed 10 millimeters "actual", i.e. if you placed a ruler against it its length would be 10 mm. This is primarily for plotted (or printed) output and is computed using the plot scale of the window being plotted (or printed). See window.plot_scale. For display of 10 mm on the screen, a window's plot_scale should be set to 0.
M or W	The dimension will always be displayed as 10 current modeling units (see units). When graphic entities are scaled the visual appearance of the dimension will change accordingly. A change of units will have no visual effect.
P	The dimension will always be displayed as 10 screen pixels, irrespective of window scale or current modeling units.
R	The dimension will always be displayed as 10 meters displayed appropriately according to the current value of units. Subsequently when graphic entities are scaled the visual appearance of the dimension will change accordingly. A change of units will have a visual effect because the current units-to-meters ratio will have changed.
T	The dimension will always be displayed as 10 points (a point is 1/72"), irrespective of window scale or current modeling units.

See Also

Identifiers:	units (string)