Illustrator and macOS have been around for many years, so system compatibility can get confusing; however, this list and very minor modifications to Xcode will fix you up.
Xcode 10 or above is required to develop Illustrator plug-ins for macOS using CORE. We have tested full compatibility up to Xcode 16.0.
To be able to compile against all versions of CORE, your Xcode app will need to be modified for legacy support. We recommend downloading Xcode 16.0, 12.5, 12.0, and 10.3. Otherwise, you will only be able to compile against the version of CORE corresponding to the macOS SDK versions listed above.
Only the older macOS SDKs are required to develop for older versions of Illustrator in Xcode 16 (not e.g. the older compilers or linkers); if you'd like to modify Xcode 12-16 to compile for all versions of Illustrator, simply extract the MacOSX10.14.sdk, MacOSX10.15.sdk, and MacOSX11.3.sdk folders from each older version of Xcode and copy them into the Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs folder of Xcode 12-16, and modify the associated Info.plist file there to remove the "MinimumSDKVersion" entry.
You might find that the OS 10.14 and 10.15 SDKs are lacking the standard C++ #include headers; in this case, extract the OS 10.13 SDK from Xcode 9.4, and copy the MacOSX10.13.sdk/usr/include/c++ folder to the same "include" subfolder in the OS 10.14 and 10.15 SDKs.
Microsoft Visual Studio 2022 or above is required to develop Illustrator plug-ins for Windows using CORE.
Hot Door uses Microsoft Visual Studio 2022 and has not tested later versions.
No modifications or additional downloads are needed to develop plug-ins for Illustrator 2021 through 2025 (25-29).
CORE contains four sample plug-ins: Annotate, Panel, Skeleton, and Tool.
The Annotate sample implements a simple rectangle drawing tool, which annotates its geometry during dragging.
The Skeleton sample simply acts as an empty plugin that performs no function, but which Illustrator recognizes and loads successfully. This is to provide a good foundation on which to start building your own plugin (see below).
The Tool plug-in implements a gear drawing tool. This demonstrates the creation of tools, modal dialogs with UI elements, preferences, and Illustrator art drawing.
The Panel plug-in demonstrates the creation of panels with UI elements, notifiers, timers, and Illustrator art object iteration.
The easiest way to get your plug-in started using CORE is to duplicate and modify the Skeleton plug-in as a starting point.
You have two choices at this point: either start working with Skeleton as-is and add your own code, or follow these instructions to eliminate all traces of "Skeleton" and "skel" from your project.