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<< Click to Display Table of Contents >> Navigation: Image Manager > CVB Technology > Non-destructive Overlays |
Common Vision Blox supports a variety of non-destructive overlay types:
Labels, User Objects and Overlay Plug-In Objects.
Labels are available in all the supported visual development environments, however Visual Basic has some fundamental limitations that do not allow support for User Objects.
The Overlay Plug-in objects were developed specifically to overcome the limitations of Visual Basic and allow a developer to use overlays in a fast, efficient and flexible way.
A detailed description of each of the available overlay object types is found on the following links:
Overlays of any type are identified by an object ID.
This ID can be used in further functions to find the position and to move, highlight or remove the object.
It is the responsibility of the developer to track the ID's used for creating overlays and verify that each ID is unique.
Common Vision Blox allows multiple objects with the same ID to be created, however if the user requests information using this ID then CVB will return the information for the first object found with a matching ID.
If CVB verified every object ID was unique before creating it then the application could become very slow, if the user created hundreds or thousands of overlays then the verification process would require a lot of processing time.