update README

README.md

@@ -1,7 +1,7 @@
 # Terrasaur
 
-Terrasaur is a suite of programs written in Java and C++. These stand-alone
-command line analysis and shape model manipulation programs that complement the
+Terrasaur is a suite of programs written in Java and C++. These standalone
+command line analysis and shape model manipulation programs complement the
 [Small Body Mapping Tool](https://sbmt.jhuapl.edu/) and create data products that
 are well-suited to being visualized in the SBMT GUI. Among other functions,
 these programs facilitate the building of digital terrain models (DTMs) of
@@ -20,21 +20,26 @@ The Terrasaur package requires Java 21 or later.  Some freely available versions
 * [Eclipse Temurin](https://adoptium.net/)
 * [OpenJDK](https://jdk.java.net/).  Most Linux distributions and HomeBrew have OpenJDK packages.
 
+### Download the latest release
+
+Precompiled release packages can be found on [GitHub](https://github.com/JHUAPL/Terrasaur/releases)
+
 ### Build the package
 
-This is an optional step if you don't want to use the prebuilt
-package.  Check out the code:
+If you don't want to use the prebuilt package,  check out the code:
 
     git clone https://github.com/JHUAPL/Terrasaur.git
 
 The 3rd party executables and libraries are assumed to exist in
 `3rd-party/$(uname -s)_$(uname -m)` (e.g. `3rd-party/Darwin_x86_64` on an
 Intel macOS machine).  The script to build the 3rd party products is in the
-`support-libraries` directory.
+`support-libraries` directory.  
 
     cd support-libraries
     ./buildAll.bash ../3rd-party/$(uname -s)_$(uname -m)
 
+You can instead use the precompiled support libraries from a release package to save a lot of time.  See the `support-libraries` [README](./support-libraries/README.md).
+
 Maven must be installed to build the software.  Once the `3rd-party`
 directory has been built, compile the Terrasaur package using the
 `mkPackage.bash` script:

support-libraries/README.md

@@ -1,12 +1,26 @@
 # Supporting libraries for Terrasaur
 
-The Terrasaur code is available at [GitHub](https://github.com/JHUAPL/Terrasaur.git).  This directory contains supporting libraries needed to build Terrasaur.
+The Terrasaur code is available at [GitHub](https://github.com/JHUAPL/Terrasaur.git).  This directory contains these supporting libraries needed to build Terrasaur:
 
 * [GSL](https://www.gnu.org/software/gsl/)
 * [SPICE](https://naif.jpl.nasa.gov)
 * [VTK](https://vtk.org)
 * [OpenCV](https://opencv.org/)
 
+# Shortcut
+
+The support code may take a long time to compile (several hours in some cases).  You can instead download a binary package for your architecture from [GitHub](https://github.com/JHUAPL/Terrasaur/releases).  The compiled 3rd party products are found in the `lib` directory (e.g. `Terrasaur-YYYY.MM.DD/lib/Darwin_arm64`).  Copy or move this directory to your source directory under `3rd-party`.  For example:
+
+```
+    mkdir 3rd-party
+    tar xfz Terrasaur-YYYY.MM.DD.tar.gz
+    ln -s Terrasaur-YYYY.MM.DD/lib/Darwin_arm64 3rd-party/
+```
+
+You can now compile the Terrasaur code using the released support files.
+
+# Building the code
+
 ## Prerequisites
 
 You may need to install the following packages with 
@@ -21,10 +35,7 @@ Each subdirectory has a build script which takes a single argument,
 which is the installation location for the compiled libraries and
 executables.  
 
-The `buildAll.bash` script will build and install the libraries and executables
-to the desired location.  For example, this would install everything in a 
-directory named for your system architecture (e.g. 3rd-party/Darwin_x86_64 on 
-an intel macOS system):
+The `buildAll.bash` script will build and install the libraries and executables to the desired location.  For example, this would install everything in a directory named for your system architecture (e.g. 3rd-party/Darwin_x86_64 on an intel macOS system):
 
 ```
 ./buildAll.bash ../3rd-party/$(uname -s)_$(uname -m)