About extensibility

This chapter describes the C-level extensibility mechanism, which lets you implement Adobe Animate extensibility files using a combination of JavaScript and custom C code.

Note: Adobe Animate runs on 64-bit operating systems only. All C extensions for this release must be built (or rebuilt) for 64 bit support.

To implement extensibility, you define functions using C, bundle them in a dynamic linked library (DLL) or a shared library, save the library in the appropriate directory, and then call the functions from JavaScript using the Adobe Animate JavaScript API.
For example, you might want to define a function that performs intense calculations more efficiently than JavaScript does, which improves performance, or when you want to create more advanced tools or effects.
This extensibility mechanism is a subset of the Adobe Dreamweaver API. If you are familiar with that API, you might recognize the functions in the C-level extensibility mechanism API. However, this API differs from the Dreamweaver API in the following ways:

- This API does not contain all the commands in the Dreamweaver API.

- All declarations of type wchar_t and char in the Dreamweaver API are implemented as unsigned short declarations in this API, to support Unicode when strings are passed.

- The JSVal JS_BytesToValue() (../C-Level_Extensibility/The_C.md) function in this API is not part of the Dreamweaver API.

- The location in which the DLL or shared library files must be stored is different (see "Integrating C functions" (../C-Level_Extensibility/Integrating_C_functions.md)).

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