From 1d75ec0639026c3fca621d6f1c28694c932b6af7 Mon Sep 17 00:00:00 2001
From: ehofman <ehofman>
Date: Sat, 29 Apr 2006 11:14:36 +0000
Subject: [PATCH] Add support for a binary output mode.

---
 Protocol/README.Protocol | 16 +++++++++++--
 Protocol/bintest.xml     | 51 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 65 insertions(+), 2 deletions(-)
 create mode 100644 Protocol/bintest.xml

diff --git a/Protocol/README.Protocol b/Protocol/README.Protocol
index 32a4e189e..cd2159f44 100644
--- a/Protocol/README.Protocol
+++ b/Protocol/README.Protocol
@@ -1,5 +1,5 @@
 The generic communication protocol for FlightGear provides a powerfull way
-of adding a simple ASCII based output only protocol, just by defining an
+of adding a simple ASCII based or binary protocol, just by defining an
 XML encoded configuration file.
 
 The definition of the protocol consists of variable separators, line separators,
@@ -16,8 +16,9 @@ Each chunck defines:
 			%s	string
 			%i	integer	(default)
 			%f	float
+		(not used or needed in binary mode)
 
-<factor>	an optionale multiplication factor which can be used for
+<factor>	an optional multiplication factor which can be used for
 		unit conversion. (for example, radians to degrees).
 <offset>	an optional offset which can be used for unit conversion.
 		(for example, degrees Celsius to degrees Fahrenheit).
@@ -44,6 +45,16 @@ any other charachters just need to be added to "Network/generic.cxx"
 The var_separator is placed between each variable, while the line_separator is
 placed at the end of each lot of variables.
 
+To enable binary mode, simply include a <binary_mode>true</binary_mode> tag in
+your XML file. The format of the binary output is tightly packed, with 1 byte
+for bool, 4 bytes for int, and 8 bytes for double. At this time, strings are not
+supported. A configurable footer at the end of each "line" or packet of binary
+output can be added using the <binary_footer> tag. Options include the length
+of the packet, a magic number to simplify decoding. Examples:
+
+	<binary_footer>magic,0x12345678</binary_footer>
+	<binary_footer>length</binary_footer>
+	<binary_footer>none</binary_footer>			<!-- default -->
 
 A simple protocol configuration file then could look something like the
 following:
@@ -57,6 +68,7 @@ following:
   <output>
    <line_separator>newline</line_separator>
    <var_separator>newline</var_separator>
+   <binary_mode>false</binary_mode>
 
    <chunk>
     <name>speed</name>
diff --git a/Protocol/bintest.xml b/Protocol/bintest.xml
new file mode 100644
index 000000000..8dfaf5588
--- /dev/null
+++ b/Protocol/bintest.xml
@@ -0,0 +1,51 @@
+<?xml version="1.0"?>
+
+<PropertyList>
+
+ <generic>
+
+  <output>
+   <binary_mode>true</binary_mode>
+   <binary_footer>magic,0x12345678</binary_footer>
+
+   <chunk>
+    <name>indicated speed (kt)</name>
+    <type>int</type>
+    <node>/velocities/airspeed-kt</node>
+   </chunk>
+ 
+   <chunk>
+    <name>pitch att (deg)</name>
+    <type>float</type>
+    <node>/orientation/pitch-deg</node>
+   </chunk>
+
+   <chunk>
+    <name>magnetic heading (deg)</name>
+    <type>float</type>
+    <node>/orientation/heading-deg</node>
+   </chunk>
+
+   <chunk>
+    <name>outside air temperarure (degF)</name>
+    <type>int</type>
+    <node>/environment/temperature-degf</node>
+   </chunk>
+
+   <chunk>
+    <name>autocoord</name>
+    <type>boolean</type>
+    <node>/sim/auto-coordination</node>
+   </chunk>
+
+   <chunk>
+    <name>clock</name>
+    <type>string</type>
+    <node>/instrumentation/clock/indicated-string</node>
+   </chunk>
+
+  </output>
+
+ </generic>
+
+</PropertyList>