--- ray/INSTALL.scons	2009/10/22 20:50:27	1.2
+++ ray/INSTALL.scons	2016/04/19 21:21:23	1.5
@@ -10,8 +10,9 @@ Requirements
 ------------
 
 Please make sure that you have dowloaded and unpacked BOTH the Radiance
-source package AND the archive with the auxiliary files. Crucial parts
-of the system will be missing if you only have one of them.
+source package AND the archive with the auxiliary support files.
+Crucial parts of the system will be missing if you only have one of
+them, and SCons will be unable to build the software.
 
 SCons is a platform-independent software configuration and build system
 written in Python. If SCons and Python are not already installed on your
@@ -24,11 +25,21 @@ For many systems, precompiled packages are available, 
 files for Windows. Most Linux distributions already come with Python
 installed and ready to use.
 
-SCons *may* use a libtiff already installed on your system. However, if
-it doesn't find one, it will build its own from sources included with
-Radiance.
+SCons *may* use a libtiff already installed on your system. On posix
+systems it usually does. Otherwise the executables requiring it are
+not built.
 
+On Windows, Radiance gets built with MS Visual Studio if present, the
+community editions are sufficient.
+VS 2013 is currently the most recent version that does it correctly.
+VS 2015 also performs the build, but it uses the new "universal CRT"
+from Windows 10, which has a bug that corrupts data in text pipes.
+A fix is apparently ready and should be released via autoupdate,
+probably around the time of the "anniversary update" in summer 2016.
+Older versions of VS may work as well, but haven't been tested with
+the current sources.
 
+
 Building
 --------
 
@@ -54,7 +65,7 @@ files for various build environments. In this context,
 specific combination of operating system and build tools (eg. compiler).
 On unix based systems, the compiler usually doesn't make much of a
 difference, but on Windows, there are seperate build environments for
-toolkits like Cygwin or MingW.
+toolkits like MingW.
 
 The file "ray/platform/README" explains the settings that can be
 configured in those files, and how to create a new one, if you use a
@@ -87,6 +98,11 @@ RAD_DEBUG=1|0
 SKIP=1|0
 	1: Skip display of License terms
 	0: Don't skip (default)
+
+MSVC_VERSION=12.0|14.0
+	"12.0" is the default for Visual Studio 2013.
+	Once the text pipe bug in the universal CRT is fixed, the default
+	will be changed to "14.0" for Visual Studio 2015.
 
 SCons will remember the values given with those options. You don't need
 to supply them again each time when you run repeated builds and