Remove packman dependencies

physx/CMAKE_VCPKG_CHANGES.md

@@ -0,0 +1,145 @@
+# CMake Changes for vcpkg Support
+
+## Overview
+Update CMake files to detect and use vcpkg-provided packages on Windows while maintaining backward compatibility with packman.
+
+## Detection Strategy
+
+Detect vcpkg by checking if `CMAKE_TOOLCHAIN_FILE` contains "vcpkg":
+```cmake
+if(DEFINED CMAKE_TOOLCHAIN_FILE AND CMAKE_TOOLCHAIN_FILE MATCHES "vcpkg")
+    set(USING_VCPKG TRUE)
+else()
+    set(USING_VCPKG FALSE)
+endif()
+```
+
+## Files to Modify
+
+### 1. snippets/compiler/cmake/SnippetVehicleTemplate.cmake
+
+**Current code (lines 34-44):**
+```cmake
+# Use system RapidJSON instead of packman version
+IF(UNIX AND NOT APPLE)
+	# Linux: Use system-installed rapidjson-dev package
+	SET(PM_RAPIDJSON_INCLUDE_PATH "/usr/include")
+ELSE()
+	# Windows/Mac: Fall back to packman if PM_rapidjson_PATH is set
+	IF(NOT PM_RAPIDJSON_PATH_INTERNAL)
+		SET(PM_RAPIDJSON_PATH_INTERNAL $ENV{PM_rapidjson_PATH} CACHE INTERNAL "rapidjson package path")
+	ENDIF()
+	SET(PM_RAPIDJSON_INCLUDE_PATH ${PM_RAPIDJSON_PATH_INTERNAL}/include)
+ENDIF()
+```
+
+**Proposed changes:**
+```cmake
+# Detect vcpkg usage
+if(DEFINED CMAKE_TOOLCHAIN_FILE AND CMAKE_TOOLCHAIN_FILE MATCHES "vcpkg")
+    set(USING_VCPKG TRUE)
+else()
+    set(USING_VCPKG FALSE)
+endif()
+
+# Configure RapidJSON include path based on platform and package manager
+IF(UNIX AND NOT APPLE)
+	# Linux: Use system-installed rapidjson-dev package
+	SET(PM_RAPIDJSON_INCLUDE_PATH "/usr/include")
+ELSEIF(USING_VCPKG)
+	# Windows/Mac with vcpkg: Use vcpkg-provided rapidjson
+	# vcpkg automatically sets up include paths via CMAKE_TOOLCHAIN_FILE
+	# RapidJSON is header-only, so we just need to find it
+	find_path(RAPIDJSON_INCLUDE_DIR rapidjson/rapidjson.h)
+	if(RAPIDJSON_INCLUDE_DIR)
+		SET(PM_RAPIDJSON_INCLUDE_PATH ${RAPIDJSON_INCLUDE_DIR})
+		message(STATUS "Using vcpkg RapidJSON at: ${PM_RAPIDJSON_INCLUDE_PATH}")
+	else()
+		message(FATAL_ERROR "RapidJSON not found via vcpkg. Install with: vcpkg install rapidjson")
+	endif()
+ELSE()
+	# Windows/Mac: Fall back to packman if PM_rapidjson_PATH is set
+	IF(NOT PM_RAPIDJSON_PATH_INTERNAL)
+		SET(PM_RAPIDJSON_PATH_INTERNAL $ENV{PM_rapidjson_PATH} CACHE INTERNAL "rapidjson package path")
+	ENDIF()
+	SET(PM_RAPIDJSON_INCLUDE_PATH ${PM_RAPIDJSON_PATH_INTERNAL}/include)
+ENDIF()
+```
+
+### 2. snippets/compiler/cmake/windows/SnippetVehicleTemplate.cmake
+
+**Current code (lines 31-33):**
+```cmake
+IF(NOT FREEGLUT_PATH)
+	SET(FREEGLUT_PATH $ENV{PM_freeglut_PATH} CACHE INTERNAL "Freeglut package path")
+ENDIF()
+```
+
+**Proposed changes:**
+```cmake
+# Detect vcpkg usage
+if(DEFINED CMAKE_TOOLCHAIN_FILE AND CMAKE_TOOLCHAIN_FILE MATCHES "vcpkg")
+    set(USING_VCPKG TRUE)
+else()
+    set(USING_VCPKG FALSE)
+endif()
+
+IF(USING_VCPKG)
+	# Use vcpkg-provided FreeGLUT
+	find_package(GLUT REQUIRED)
+	# vcpkg's FindGLUT will set GLUT_LIBRARIES and GLUT_INCLUDE_DIR
+	SET(FREEGLUT_LIB ${GLUT_LIBRARIES})
+	message(STATUS "Using vcpkg FreeGLUT")
+ELSE()
+	# Use packman FreeGLUT
+	IF(NOT FREEGLUT_PATH)
+		SET(FREEGLUT_PATH $ENV{PM_freeglut_PATH} CACHE INTERNAL "Freeglut package path")
+	ENDIF()
+
+	# Keep existing packman FREEGLUT_LIB configuration
+	SET(FREEGLUT_LIB
+		$<$<CONFIG:debug>:${FREEGLUT_PATH}/lib/win${LIBPATH_SUFFIX}/freeglutd.lib>
+		$<$<CONFIG:checked>:${FREEGLUT_PATH}/lib/win${LIBPATH_SUFFIX}/freeglut.lib>
+		$<$<CONFIG:profile>:${FREEGLUT_PATH}/lib/win${LIBPATH_SUFFIX}/freeglut.lib>
+		$<$<CONFIG:release>:${FREEGLUT_PATH}/lib/win${LIBPATH_SUFFIX}/freeglut.lib>
+	)
+ENDIF()
+```
+
+### 3. Similar Changes for Other Templates
+
+Apply similar logic to:
+- `snippets/compiler/cmake/SnippetTemplate.cmake`
+- `snippets/compiler/cmake/windows/SnippetTemplate.cmake`
+- `snippets/compiler/cmake/SnippetRender.cmake`
+- `snippets/compiler/cmake/windows/SnippetRender.cmake`
+
+## Testing on Windows
+
+After making these changes, test with:
+
+```bash
+# With vcpkg
+generate_projects_vcpkg.bat windows-vc16
+cmake --build compiler\windows-vc16-release\ --config Release
+
+# With packman (backward compatibility test)
+generate_projects.bat windows-vc16
+```
+
+Both should work!
+
+## Key Points
+
+1. **Backward compatible**: Packman still works if vcpkg not detected
+2. **Automatic detection**: No manual flags needed, detects vcpkg toolchain file
+3. **Clear errors**: If vcpkg is used but packages missing, fails with clear message
+4. **Platform-specific**: Linux uses apt-get, Windows can use vcpkg, both supported
+
+## Next Steps for Windows Session
+
+1. Install vcpkg on Windows
+2. Apply these CMake changes
+3. Test generation and build
+4. Update README.md with Windows instructions
+5. Commit and push