From aee97300aa5dab4b5581f90551939d5849a7443b Mon Sep 17 00:00:00 2001
From: Mark Leone <mleone@nvidia.com>
Date: Mon, 1 Aug 2022 12:07:27 -0600
Subject: [PATCH] Added OTK_BUILD_GUI flag to control building the Gui library.
 OTK_BUILD_EXAMPLES must also be turned off in order for it to work.

---
 CMake/OptiXToolkitConfig.cmake.in |  2 +-
 CMakeLists.txt                    | 15 ++++++++++-----
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/CMake/OptiXToolkitConfig.cmake.in b/CMake/OptiXToolkitConfig.cmake.in
index 603a0db8..daae6e13 100644
--- a/CMake/OptiXToolkitConfig.cmake.in
+++ b/CMake/OptiXToolkitConfig.cmake.in
@@ -41,6 +41,6 @@ find_package(OptiX REQUIRED)
 # Import the targets.
 include("${_prefix}/cmake/OptiXToolkit/CudaTargets.cmake")
 include("${_prefix}/cmake/OptiXToolkit/UtilTargets.cmake")
-include("${_prefix}/cmake/OptiXToolkit/GuiTargets.cmake")
 include("${_prefix}/cmake/OptiXToolkit/ImageSourceTargets.cmake")
 include("${_prefix}/cmake/OptiXToolkit/DemandLoadingTargets.cmake")
+include("${_prefix}/cmake/OptiXToolkit/GuiTargets.cmake" OPTIONAL)
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9056f571..67d75c6e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -66,18 +66,23 @@ install(FILES ${OptiXToolkit_BINARY_DIR}/CMake/OptiXToolkitConfig.cmake
 #########################################################
 # Subdirectories
 
+option( OTK_BUILD_EXAMPLES "Enable build of OptiXToolkit examples" ON )
+option( OTK_BUILD_DOCS "Enable build of OptiXToolkit documentation" ON)
+option( OTK_BUILD_GUI "Enable build of Gui library" ON )
+
+if( OTK_BUILD_GUI OR OTK_BUILD_EXAMPLES )
+  add_subdirectory(Gui)
+endif()  
+
 add_subdirectory(Cuda)
 add_subdirectory(Util)
-add_subdirectory(Gui)
 add_subdirectory(ImageSource)
 add_subdirectory(DemandLoading)
 
-set( OTK_BUILD_EXAMPLES ON CACHE BOOL "Enable build of OptiXToolkit examples" )
-if( ${OTK_BUILD_EXAMPLES} )
-  add_subdirectory(examples)
+if( OTK_BUILD_EXAMPLES )
+   add_subdirectory(examples)
 endif()
 
-set( OTK_BUILD_DOCS ON CACHE BOOL "Enable build of OptiXToolkit documentation" )
 if( OTK_BUILD_DOCS )
   add_subdirectory( docs/API )
 endif()