Google Flix Engine Linux Reference Manual Instrukcja Użytkownika Pobierz pdf (Strona 345)

7.2 Language Binding API Deviations 339

7.2 Language Binding API Deviations

The Flix Engine language bindings endeavor to remain as true as possible to the Flix Engine API. In certain

cases, however, the C implementation does not transfer directly. This guide will provide an overview of

the changes, both necessary and those done for the sake of convenience. Currently Flix Engine has support

for Java, Perl, PHP and Python.

The main differences include:

• how Flix Engine handles are created

• how Codec handles are created

• how Filter handles are created

• how constants are referenced

• how functions that return values via a result parameter accomplish this

A word on Java:

For better consistency with Java function call semantics, the Java bindings consist of three main wrap-

per classes, FlixEngine2, Codec and Filter. In addition to this, each enumeration becomes its own

class. Javadoc documentation is provided to highlight these differences. If you chose to install the

Java bindings, the Javadoc will be installed by default in:

/usr/local/src/flixmodules/flixjava/doc

Attention:

The language bindings need only be rebuilt should the CHANGELOG note changes to the interface,

e.g., the addition of constants/functions. Without rebuilding, these new features will be unavailable and

depending on the bindings being used will either generate a compile error or, in the case of constants,

will return ON2_NOT_SUPP should they be used.

7.2.1 Flix Engine Handle Creation

When creating a handle to the Flix Engine one calls

Flix2_Create() or Flix2_CreateEx() with a pointer to a

FLIX2HANDLE, allowing the value of the handle to be stored back to this location. So for example:

FLIX2HANDLE flix;

Flix2_Create(&flix);

...upon success flix holds the address of the handle...

When dealing with various interpreted languages there is no way to directly accomplish this. For this

reason a helper function is introduced to ﬁrst create a storage location for the handle. Note that though the

following is in Perl, the helper functions carry over to all of the language bindings.

$flixptr= new_flix2handlep();

We can now use this storage location to create a new handle to the engine:

Flix2_Create($flixptr);

Before we use the new handle in the remaining API functions we have to retrieve its actual value. Another

helper function is introduced for this purpose:

Generated on Tue Jul 20 17:39:03 2010 for Flix Engine Linux by Doxygen

1 2 ... 340 341 342 343 344 345 346 347 348 349 350 ... 544 545

Brak uwag

Google Flix Engine Linux Reference Manual Instrukcja Użytkownika Strona 345