Raise minimum CMake version to 3.16

This changelist raises the minimum CMake version to 3.16, allowing more modern CMake features to be leveraged in future pull requests.

CMake 3.16 is the first version that natively supports Objective C++ files, which are an important component of the Metal Shading Language support in MaterialX.

CMakeLists.txt

@@ -5,7 +5,7 @@ set(MATERIALX_BUILD_VERSION 9)
 set(MATERIALX_LIBRARY_VERSION ${MATERIALX_MAJOR_VERSION}.${MATERIALX_MINOR_VERSION}.${MATERIALX_BUILD_VERSION})
 
 # Cmake setup
-cmake_minimum_required(VERSION 3.5)
+cmake_minimum_required(VERSION 3.16)
 set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_POSITION_INDEPENDENT_CODE TRUE)
 set(CMAKE_MACOSX_RPATH ON)
@@ -339,14 +339,12 @@ if(MATERIALX_BUILD_JS)
     add_subdirectory(source/JsMaterialX)
 endif()
 
-if(${CMAKE_VERSION} VERSION_GREATER "3.6.2")
-    if(MATERIALX_BUILD_VIEWER)
-        set_property(DIRECTORY PROPERTY VS_STARTUP_PROJECT MaterialXView)
-    elseif(MATERIALX_BUILD_GRAPH_EDITOR)
-        set_property(DIRECTORY PROPERTY VS_STARTUP_PROJECT MaterialXGraphEditor)
-    elseif(MATERIALX_BUILD_TESTS)
-        set_property(DIRECTORY PROPERTY VS_STARTUP_PROJECT MaterialXTest)
-    endif()
+if(MATERIALX_BUILD_VIEWER)
+    set_property(DIRECTORY PROPERTY VS_STARTUP_PROJECT MaterialXView)
+elseif(MATERIALX_BUILD_GRAPH_EDITOR)
+    set_property(DIRECTORY PROPERTY VS_STARTUP_PROJECT MaterialXGraphEditor)
+elseif(MATERIALX_BUILD_TESTS)
+    set_property(DIRECTORY PROPERTY VS_STARTUP_PROJECT MaterialXTest)
 endif()
 
 # Install root-level documents

source/MaterialXGraphEditor/CMakeLists.txt

@@ -9,7 +9,7 @@ if (NOT IS_DIRECTORY "${DEAR_IMGUI_PREFIX}/backends")
 endif()
 
 if(MSVC)
-    add_compile_options(-wd4100)
+    add_compile_options(-wd4100 -wd4152 -wd4201 -wd4244 -wd4456)
 elseif(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
     add_compile_options(-Wno-unused -Wno-deprecated -Wno-comment -Wno-unused-variable)
 elseif(CMAKE_CXX_COMPILER_ID MATCHES "GNU")