Add FindDirectX.cmake module for robust SDK detection (#9)

Author: bobtista

CMakeLists.txt

@@ -216,13 +216,14 @@ target_sources(unassemblize PRIVATE
 
 # Platform-specific configurations
 if(WINDOWS)
+    find_package(DirectX REQUIRED)
     target_sources(unassemblize PRIVATE
         src/imguiclient/imguiwin32.cpp
         src/imguiclient/imguiwin32.h
     )
 
     target_link_libraries(unassemblize PRIVATE
-        d3d9.lib # TODO: figure out if any "FindDirectX" logic is needed here.
+        DirectX::D3D9
         imgui_win32
         ${DIASDK_LIBRARIES}
     )

cmake/FindDirectX.cmake

@@ -0,0 +1,78 @@
+# FindDirectX.cmake
+#
+# Finds DirectX SDK through the Windows SDK or legacy DirectX SDKs
+#
+# Sets up:
+# DirectX_FOUND - System has DirectX SDK
+# DirectX_INCLUDE_DIRS - DirectX include directories
+# DirectX_LIBRARIES - DirectX libraries
+# DirectX_D3D9_LIBRARY - Path to d3d9.lib
+
+include(FindPackageHandleStandardArgs)
+
+# Determine architecture
+if (CMAKE_SIZEOF_VOID_P EQUAL 8)
+    set(DIRECTX_ARCHITECTURE x64)
+else()
+    set(DIRECTX_ARCHITECTURE x86)
+endif()
+
+# Windows SDK and DirectX SDK paths
+set(DIRECTX_ROOT_DIR
+    "$ENV{WINDOWSSDKDIR}"  # Primary Windows SDK location from environment
+    "C:/Program Files (x86)/Windows Kits/10"  # Windows 10+ SDK base path
+    "C:/Program Files (x86)/Windows Kits/8.1"  # Windows 8.1 SDK
+    "C:/Program Files (x86)/Microsoft DirectX SDK (June 2010)"  # Legacy DirectX SDK
+    "C:/Program Files (x86)/Microsoft DirectX 9.0 SDK (Summer 2004)"  # Very old DirectX SDK
+    "C:/DXSDK"  # Another common legacy DirectX SDK location
+)
+
+# Find DirectX headers
+find_path(DirectX_INCLUDE_DIR
+    NAMES d3d9.h
+    PATHS ${DIRECTX_ROOT_DIR}
+    PATH_SUFFIXES
+        "Include/*/um"      # Windows SDK - any version
+        "Include/um"        # Windows SDK - fallback
+        "Include"           # Legacy DirectX SDK
+)
+
+# Find DirectX libraries
+find_library(DirectX_D3D9_LIBRARY
+    NAMES d3d9
+    PATHS ${DIRECTX_ROOT_DIR}
+    PATH_SUFFIXES
+        "Lib/*/um/${DIRECTX_ARCHITECTURE}"      # Windows SDK - any version
+        "Lib/um/${DIRECTX_ARCHITECTURE}"        # Windows SDK - fallback
+        "Lib/${DIRECTX_ARCHITECTURE}"           # Legacy DirectX SDK
+)
+
+# Handle the QUIETLY and REQUIRED arguments and set DirectX_FOUND
+find_package_handle_standard_args(DirectX
+    REQUIRED_VARS
+        DirectX_INCLUDE_DIR
+        DirectX_D3D9_LIBRARY
+    FAIL_MESSAGE "DirectX not found. Please ensure either Windows SDK or DirectX SDK is installed."
+)
+
+if(DirectX_FOUND)
+    # Add some debug messages to help troubleshoot paths
+    message(STATUS "DirectX Include Dir: ${DirectX_INCLUDE_DIR}")
+    message(STATUS "DirectX D3D9 Library: ${DirectX_D3D9_LIBRARY}")
+
+    set(DirectX_INCLUDE_DIRS ${DirectX_INCLUDE_DIR})
+    set(DirectX_LIBRARIES ${DirectX_D3D9_LIBRARY})
+
+    if(NOT TARGET DirectX::D3D9)
+        add_library(DirectX::D3D9 UNKNOWN IMPORTED)
+        set_target_properties(DirectX::D3D9 PROPERTIES
+            IMPORTED_LOCATION "${DirectX_D3D9_LIBRARY}"
+            INTERFACE_INCLUDE_DIRECTORIES "${DirectX_INCLUDE_DIR}"
+        )
+    endif()
+endif()
+
+mark_as_advanced(
+    DirectX_INCLUDE_DIR
+    DirectX_D3D9_LIBRARY
+)

cmake/imgui.cmake

@@ -23,6 +23,7 @@ set(IMGUI_HEADERS
 )
 
 if(WINDOWS)
+    find_package(DirectX REQUIRED)
     add_library(imgui_win32 STATIC ${IMGUI_SOURCES}
         ${IMGUI_DIR}/backends/imgui_impl_dx9.cpp
         ${IMGUI_DIR}/backends/imgui_impl_win32.cpp
@@ -47,7 +48,7 @@ if(WINDOWS)
     )
 
     # Windows uses DirectX, no need for OpenGL
-    target_link_libraries(imgui_win32 PRIVATE d3d9)
+    target_link_libraries(imgui_win32 PRIVATE DirectX::D3D9)
     set(IMGUI_LIBRARY imgui_win32)
 else()
     # Linux and macOS use OpenGL3