Visual Studio builds: Mention about Vulkan builds

Let people know what is needed for Vulkan builds.

diff --git a/build/win32/vs12/README.txt b/build/win32/vs12/README.txt
index 2abcd661ffa5a0972aaddbd37e616bf73718dcbb..58cd1872e067641e23aa569e4b2773a9578982c6 100644 (file)
--- a/build/win32/vs12/README.txt
+++ b/build/win32/vs12/README.txt
@@ -34,6 +34,14 @@ possible, especially those from and using the GTK+ stack (i.e. GLib,
 Cairo, ATK, Pango, GDK-Pixbuf), so that crashes caused by mixing calls\r
 to different CRTs can be kept at a minimum.\r
 \r
+To build with Vulkan renderer support, use the configs that end with _Vulkan.\r
+You will need the LunarG Vulkan SDK installed, and its include\ directory\r
+and Bin\ (64-bit) or Bin32 (32-bit) need to be in your INCLUDE and LIB paths\r
+(or need to be set in your additional include paths and additional library paths)\r
+so that they can be found by the build.  To run with the Vulkan renderer, set\r
+GSK_RENDERER=vulkan--you will need a video adapter with driver support for Vulkan\r
+to support this.\r
+\r
 zlib, libpng, and Cairo do contain support for compiling under VS12\r
 using VS project files and/or makefiles at this time of writing, For the\r
 GTK+ stack, VS12 project files are either available under\r