Update XPLM for ARM64

XPSDK/README.txt

@@ -5,24 +5,12 @@
 This download contains the files necessary to build plugins for X-Plane.  The 
 X-Plane plugin website is:
 
-http://www.xsquawkbox.net/xpsdk/
+http://https://developer.x-plane.com/sdk/
 
 The website contains full documentation on the SDK including tech notes, sample
 plugins, sample code, contact information, and links to the latest versions of
 this SDK.
 
-The X-Plane SDK authors can be reached at:
-
-xplanesdk@xsquawkbox.net
-
-Please do not email Austin or Laminar Research for SDK questions or support;
-the SDK is a third party effort.
-
-the X-Plane developer mailing list is an unlisted yahoo group frequented by 
-many X-Plane developers.
-
-x-plane-dev@yahoogroups.com
-
 -------------------------------------------------------------------------------
                                   SDK FILES
 -------------------------------------------------------------------------------
@@ -32,25 +20,62 @@ README.txt	This document
 CHeaders	Header files for compiling C/C++ plugins
 Delphi		Interfaces for compiling Pascal plugins
 Libraries	Import libraries for linking on Windows
-		and frameworks for linking on Mac.
+            and frameworks for linking on Mac.
 
 Note: there are no import/link-time libraries for Linux; on Linux, plugins
 simply leave SDK symbols undefined and they are discovered at runtime.  The 
 SDK website explains this process in more detail.
 
-Mac CFM plugins are not supported by the SDK versions 2.0 and higher; the 
-2.0 SDK requires X-Plane 9.0 or newer, and X-Plane 9 will not run on 
-Mac OS 9.  Therefore CFM plugins are not useful (and are probably 
-counterproductive since they cannot support x86 code).  If you have a CFM 
-plugin, continue to use the 1.0 SDK to build it. You will have to port to 
-Mach-O if you want to use 2.0 features.
-
 -------------------------------------------------------------------------------
                               RELEASE NOTES
 -------------------------------------------------------------------------------
 
 This section contains per-release notes for the history of the X-Plane SDK.
 
+X-PLane SDK Release 4.0.0 beta 1 9/18/2022
+
+The 4.0.0 SDK adds support for ARM64 Macs.  The 4.0 SDK is supported by X-Plane
+12.  The new SDK adds support for drawing hooks that draw directly to the G1000
+and other avionic cockpit devices.
+
+X-Plane SDK Release 3.0.2 4/29/2020
+
+The SDK 3.0.2 adds the modern 3-d drawing callback for interoperability with
+Metal and Vulkan, and deprecates most older drawing callbacks.
+
+X-Plane SDK Release 3.0.1 3/5/2018
+
+The SDK 3.0.1 API adds new messages and APIs to support VR.
+
+X-Plane SDK Release 3.0.0 11/2/7/2017
+
+The SDK 3.0 API supports new features and new packaging for plugins. The 3.0
+SDK requires X-Plane 11.0 or newer. New features include:
+
+ - Display APIs to match X-Plane 11's UI.
+ - New map APIs. Legacy 2-d map draw callbacks are deprecated.
+ - Aircraft-plugins get their own menu
+ - Aircraft placement by lat-lon-elevation.
+ - Magnetic variation queries
+ - Chinese language support
+ - New instancing API
+
+The 3.0 SDK supports a new plugin packaging schema:
+
+    <plugin name>/<ABI>/<plugin name>.xpl
+
+where ABI is one of mac_x64, win_x64 or lin_x64. The new schema is preferred,
+so you can pack a version of your plugin that requires 3.0 with this scheme
+and include a legacy 2.x plugin using hte old scheme for X-Plane 10 
+compatibility.
+
+Please use the new scheme where possible - having a unique file name for each
+DLL makes crash reports easier to read and triage.
+
+The 3.0 SDK drops support for 32-bit plugins; if you need to ship a 32-bit 
+plugin for 32-bit X-Plane 10, shipping using two schemes and two binaries may
+be the best option.
+
 X-Plane SDK Release 2.1.3 11/14/13
 
 Fixed XPC Wrappers to use int and intptr_t instead of long.  This fixes