HALCON/COM User's Manual

Chapter 2
The HALCON COM Interface
This chapter describes the structure of the HALCON/COM interface. Please note, that there are
several interesting facts to know about COM that are not discussed here, because they are not
directly relevant for working with the HALCON/COM interface. Thus, you are recommended
to read additional COM-related literature and/or the documentation of your preferred development
tool (e.g. Visual Basic). At least you should be familiar with object oriented concepts like
inheritance, classes and methods in order to understand the following chapter.
2.1 Preface
Let’s have a closer look at the HALCON/COM interface. The whole package (called the
HalconX library) contains all the functionality partitioned into several classes. Each class has
one or more interfaces that are built up from methods and properties. The HALCON/COM
interface uses inheritance and thus contains derived classes and also an abstract base class.
Since COM is not meant to supply a standardized inheritance mechanism, HALCON/COM
makes extensive use of interfaces to simulate inheritance (we will discuss this topic more
detailled afterwards).
Naming Conventions:
º classes are capitalized and begin with an “H”. They always end with an upper-case “X”;
for example: ÀÖÑÖÖ.
º interfaces are also capitalized and end with “X”, but begin with an “I”; for example:
ÁÀÇØ.
º methods, properties and parameters are capitalized; for example: ÖÁÑ, ÐÆÑ.
Since COM is only available for the Windows operating systems family, all file paths and environment
variables in this manual are printed in the Windows NT convention, e.g.,
±ÀÄÇÆÊÇÇ̱ÜÑÔÐ×ÚÅÒÙÐ
to denote a subdirectory containing an example package within the HALCON base directory
referenced by the environment variable ÀÄÇÆÊÇÇÌ.
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