Smart Labels
Smart Labels are a special (managed) type of facing
labels. They are intended to be associated with a point in 3D space.
Normally the point is the center of its parent entity.
Smart Labels are arranged automatically on the screen so they do not overlap and
positioned close to the point they are associated with.
See its behaiviour on the Labels>Smart labels example in the Sample Explorer
Smart labels are items. They can be a top-level item
or, most often, a child item of an entity.
By default a smart label is positioned on top of its parent object or its
associated point. When the label does not fit silhouette of its parent object it
is positioned on margins of the 3D window. In any case labels are arranged
automatically to avoid overlapping.
Array of all smart labels and related properties are maintaned by Smart Label
Manager, which can be accessed via
ISmartLabelManager_DG interface queried
from IView_DG.
An individual smart label can be accessed via
ILabel_DG
queried from the relevant IEntity_DG or
via
ISmartLabelManager_DG.GetLabel().
The Smart Label Manager also implements
IDynamicScreenItemManager_DG
interface to control smart labels as a generic set of items.
Smart Label Manager keeps a special label, which acts as a template for new
labels created with AddNewLabel, CreateLabelsAutomatic
or CreateObjectLabelAutomatic.
Properties of the template can be accessed via ISmartLabelManager_DG.GetLabelCreationTemplate
> ILabel_DG
Extended Properties
Smart labels are computationaly intensive during rendering stage. The properties
below are related for performance. These options mostly make difference for
intersive rendering of large models like during animations. It is recommeded to
experiment with the settings to tune in the performance.
Use
ISmartLabelManager_DG.GetExtendedProperties() to access the properties.
| Property |
Description |
Type |
Parameter ID |
Default |
| FavorSpeed |
When true speed is favored over accuracy |
Boolean |
0 |
True |
| CacheHLR |
When true some extra memory and some initialisation on start is used
to accelerate Hidden Label Removal during runtime |
Boolean |
1 |
True |
| ReuseSizes |
When this option is true sizes of text boxes are calculated only
when software detects that they are out date, which sometimes can be lagging |
Boolean |
2 |
True |
| CacheFlatSectionArray |
Cache flat entity array for performance. Toggle this option twice
to update the array if new entities are addded or removed |
Boolean |
3 |
True |
| BoundingObjectScale |
Copies of bounding obejcts of all entities are scaled (down when
<1.0) by this value by hidden label removal algorithm. Clamped to valid range of
[0.1, 2.0]. Reduce to show more labels. Can be tuned in by experimenting |
Double |
0 |
0.8 |
See also: Smart Labels Sample,
|