Add asset, resource system, mesh formats, color, SDL3 display and example game

Asset directory with CMake add_asset (extension dispatched), plain file asset
access, resource/resource manager with async load thread and text loader,
URI utilities, mesh format helpers, generated color header, and example game
hooks wired through the engine.

Co-Authored-By: Claude Sonnet 5.5 <[email protected]>

CMakeLists.txt

@@ -11,6 +11,10 @@ set(CMAKE_C_STANDARD_REQUIRED ON)
 # Directories
 set(DUSK_ROOT_DIR "${CMAKE_SOURCE_DIR}")
 set(DUSK_SOURCES_DIR "${DUSK_ROOT_DIR}/src")
+set(DUSK_ASSETS_DIR "${DUSK_ROOT_DIR}/assets")
+set(DUSK_BUILT_ASSETS_DIR "${CMAKE_BINARY_DIR}/assets")
+set(DUSK_GENERATED_HEADERS_DIR "${CMAKE_BINARY_DIR}/generated")
+file(MAKE_DIRECTORY ${DUSK_GENERATED_HEADERS_DIR})
 
 project(DuskCore VERSION 1.0.0 LANGUAGES C)
 
@@ -65,9 +69,25 @@ if(DUSK_BACKTRACE)
   target_link_options(${DUSK_LIBRARY_TARGET_NAME} PUBLIC -rdynamic)
 endif()
 
+# Tools (run during the build to generate headers)
+add_subdirectory(tools)
+target_include_directories(${DUSK_LIBRARY_TARGET_NAME} PUBLIC
+  ${DUSK_GENERATED_HEADERS_DIR}
+)
+
 # Core engine code
 add_subdirectory(${DUSK_SOURCES_DIR}/dusk)
 
+# Assets, copied into <build>/assets
+include(${DUSK_ROOT_DIR}/cmake/asset/asset.cmake)
+# Separate binary dir, so <build>/assets only contains built assets.
+add_subdirectory(${DUSK_ROOT_DIR}/assets ${CMAKE_BINARY_DIR}/assets_cmake)
+dusk_assets_finalize(DuskAssets)
+add_dependencies(${DUSK_LIBRARY_TARGET_NAME} DuskAssets)
+
+# Game code
+add_subdirectory(${DUSK_SOURCES_DIR}/${DUSK_GAME})
+
 # Platform code
 foreach(DIR ${DUSK_PLATFORM_DIRS})
   add_subdirectory(${DUSK_SOURCES_DIR}/${DIR})