windowrtinstaller: Add more details to README.txt

diff --git a/windowsRuntimeInstaller/README.txt b/windowsRuntimeInstaller/README.txt
index b8cf2d372f9c488a386851d0acbbb68fd5e9fd4a..a84180272078ee62dd9b71551c4dc81986f07f74 100644 (file)
--- a/windowsRuntimeInstaller/README.txt
+++ b/windowsRuntimeInstaller/README.txt
@@ -1,21 +1,67 @@
-This folder contains the files required for building the Windows Vulkan Runtime\r
-Installer Package.\r
+This folder contains the files required for building the Windows Vulkan\r
+Runtime Installer Package.\r
 \r
 To build the Installer:\r
 \r
-   1. Install Nullsoft Install System version 3.0b1 or greater. (Available from\r
-      http://nsis.sourceforge.net/Download.)\r
-\r
-   2. Build Vulkan LoaderAndTools as described in ../BUILD.md.\r
-\r
-   3. Edit the InstallerRT.nsi file in this folder and modify the following lines\r
-      to match the version of the Windows Vulkan Runtime you wish to build:\r
-         !define VERSION_ABI_MAJOR\r
-         !define VERSION_API_MAJOR\r
-         !define VERSION_MINOR\r
-         !define VERSION_PATCH\r
-         !define VERSION_BUILDNO\r
-   \r
-   4. Right click on the InstallerRT.nsi file and select "Compile NSIS Script".\r
-      The Windows Vulkan Runtime Installer package file will be created in this\r
-      folder. The name of the installer file is VulkanRT-<version>-Installer.exe.\r
+    1. Install Nullsoft Install System version 3.0b1 or greater. (Available\r
+       from http://nsis.sourceforge.net/Download.)\r
+\r
+    2. Build Vulkan LoaderAndTools as described in ../BUILD.md.\r
+\r
+    3. Edit the InstallerRT.nsi file in this folder and modify the following\r
+       lines to match the version of the Windows Vulkan Runtime you wish to\r
+       build:\r
+\r
+          !define VERSION_ABI_MAJOR\r
+          !define VERSION_API_MAJOR\r
+          !define VERSION_MINOR\r
+          !define VERSION_PATCH\r
+          !define VERSION_BUILDNO\r
+\r
+    4. Right click on the InstallerRT.nsi file and select "Compile NSIS Script".\r
+       The Windows Vulkan Runtime Installer package file will be created in\r
+       this folder. The name of the installer file is\r
+       VulkanRT-<version>-Installer.exe.\r
+\r
+\r
+Some notes on the behavior of the Windows Vulkan Runtime Installer:\r
+\r
+   o  When VulkanRT-<version>-Installer.exe is run on a 64-bit version\r
+      of Windows, it will install both the 32 and 64 bit versions of\r
+      the Vulkan runtime.  When it is run on a 32-bit version of\r
+      Windows, it will install the 32 bit version of the Vulkan runtime.\r
+\r
+   o  The VulkanRT-<version>-Installer.exe created with the above steps\r
+      can be run in silent mode by using the /S command line option when\r
+      invoking the installer.\r
+\r
+   o  The Vulkan Runtime Installer uses "counted" installs. If the\r
+      same version of the Vulkan Runtime is installed multiple times\r
+      on a system, the Vulkan Runtime must be uninstalled the same\r
+      number of times before it is completely removed from the system.\r
+\r
+   o  If the Vulkan Runtime is already installed on a system and a\r
+      different version is subsequently installed, both versions will\r
+      then co-exist on the system. The Vulkan Runtime Installer does\r
+      not remove prior versions of the Vulkan Runtime when a newer\r
+      version is installed.\r
+\r
+   o  The Vulkan Runtime Installer installs the Vulkan loader as\r
+      C:\Windows\System32\vulkan-<version>.dll. It then compares all\r
+      versions of the loader in C:\Windows\System32 that have the\r
+      same VERSION_ABI_MAJOR as the version being installed. It selects\r
+      the most recent one of these loader files and copies it to\r
+      C:\Windows\System32\vulkan-<VERSION_ABI_MAJOR>.dll.  For example,\r
+      during the install of Vulkan Runtime version 2.0.1.1, the\r
+      following files might be present in C:\Windows\System32:\r
+\r
+           vulkan-1-1-0-2-3.dll\r
+           vulkan-1-2-0-1-0.dll\r
+           vulkan-1-2-0-1-1.dll\r
+\r
+     [Note that the first "1" in the above files is VERSION_ABI_MAJOR.\r
+     The other numbers identify the release version.] The installer\r
+     will copy the most recent one of these files (in this case\r
+     vulkan-1-2-0-1-1.dll) to vulkan-1.dll. This is repeated for\r
+     C:\Windows\SYSWOW64 on 64-bit Windows systems to set up the\r
+     32-bit loader.\r