IDisplayTransformation.ReferenceScale Property

Reference scale for computing scaled symbol sizes.

[Visual Basic .NET]
Public Property ReferenceScale As Double

[C#]
public double ReferenceScale {get; set;}

[C++]
HRESULT get_ReferenceScale(
  double* scale
);

[C++]
HRESULT put_ReferenceScale(
  double scale
);

[C++]

Parameters
scale [out, retval]
  scale is a parameter of type double
scale [in]
  scale is a parameter of type double

Product Availability

Remarks

All symbols are drawn relative to the scale value set in this property.  By default this value is zero.  Symbol size is true at the reference scale.  When the reference scale is 0, symbols are always drawn at the same size regardless of the map scale (ScaleRatio).  For example, if you set your labels to display with 10 pt font, they will appear as 10 pt text at any map scale.  When the reference scale is greater than 0, symbols are drawn at a size relative to the map scale.  For example, if you set your labels to display with 10 pt font and have a reference scale of 10,000, the labels will appear as 10 pt only at that map scale; as you zoom in, the size of all symbols increases because the size of the symbols is based on the smaller scale.

The Map object has a short-cut (IMap::ReferenceScale) directly to the ReferenceScale property on its DisplayTransformation object.

The PageLayout object does not use ReferenceScale and ScaleRatio the same way as the Map object.  In layout view, zooming in is more like a magnifying glass looking at what is going to print.  When you zoom in, you only magnify what is actually going to print.  To get this effect, the ReferenceScale is always set to zero and the ScaleRatio is always set to 1:1 (i.e., 1 inch on the screen equals one inch on the printer).  In data view however, zooming in or out, changes what gets printed - WYSIWYG (What You See Is What You Get).

See Also