restore c++ backend using swift 6's improved interop

CMakeLists.txt

@@ -1,5 +1,6 @@
 cmake_minimum_required(VERSION 3.24)
 set(CMAKE_OSX_DEPLOYMENT_TARGET "13.6" CACHE STRING "Minimum OSX version" FORCE)
+set(CMAKE_Swift_LANGUAGE_VERSION 6)
 project(cxxswift LANGUAGES CXX Swift)
 
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules")
@@ -8,4 +9,6 @@ include(AddSwift)
 
 find_library(SDL3 SDL3 REQUIRED PATHS "${CMAKE_SOURCE_DIR}/Frameworks" NO_DEFAULT_PATH)
 
-add_subdirectory(Sources)
+add_subdirectory(Sources/CppBackend)
+add_subdirectory(Sources/SDLSwift)
+add_subdirectory(Sources/SwiftFrontend)

Sources/CMakeLists.txt

@@ -1,4 +0,0 @@
-add_subdirectory(SwiftFrontend)
-add_subdirectory(SDLSwift)
-add_subdirectory(CppBackend)
-add_subdirectory(SwiftBackend)

Sources/CppBackend/ball.cpp

@@ -30,6 +30,8 @@ void Ball::update(float deltaTime) noexcept {
 }
 
 
+BallWorld::BallWorld() noexcept : balls() {}
+
 void BallWorld::add(Ball::vec2f pos, float angle, float ballSize) noexcept {
   balls.emplace_back(Ball{ pos, angle, ballSize });
 }

Sources/CppBackend/ball.hpp

@@ -34,6 +34,9 @@ public:
 struct BallWorld {
   std::vector<Ball> balls;
 
+  BallWorld() noexcept;
+  virtual ~BallWorld() noexcept = default;
+
   void add(Ball::vec2f pos, float angle, float ballSize) noexcept;
   void update(float deltaTime) noexcept;
 };

Sources/SDLSwift/module.modulemap

@@ -1,3 +1,3 @@
-module SDL3 [extern_c] {
+module SDL3 {
   header "shim.h"
 }

Sources/SwiftBackend/Backend.swift

@@ -1,7 +0,0 @@
-import CppBackend
-
-public struct FuckYou {
-  public static func fuck() {
-    let _ = BallWorld()
-  }
-}

Sources/SwiftBackend/CMakeLists.txt

@@ -1,2 +0,0 @@
-add_library(SwiftBackend STATIC Backend.swift)
-target_link_libraries(SwiftBackend PRIVATE CppBackend)

Sources/SwiftFrontend/Application.swift

@@ -1,13 +1,6 @@
-//
-//  Application.swift
-//  cxxswift
-//
-//  Created by Alex Zenla on 8/3/24.
-//
-
 import Foundation
 import SDL3
-import SwiftBackend
+import CppBackend
 
 class Application {
   private var window: OpaquePointer? = nil
@@ -15,9 +8,9 @@ class Application {
 
   private var lastCounter: UInt64 = 0
 
+  private var balls = BallWorld()
+
   private func initialize() -> ApplicationExecutionState {
-    FuckYou.fuck()
-    
     guard SDL_Init(SDL_INIT_VIDEO) >= 0 else {
       print("SDL_Init() error: \(String(cString: SDL_GetError()))")
       return .exitFailure
@@ -40,6 +33,15 @@ class Application {
     SDL_SetRenderVSync(renderer, 1)
     SDL_SetRenderLogicalPresentation(renderer, 512, 512, SDL_LOGICAL_PRESENTATION_LETTERBOX, SDL_SCALEMODE_BEST)
 
+    let ballOrigin = SIMD2(Float(width), Float(height)) * 0.5
+    for _ in 0..<10 {
+      balls.add(
+        ballOrigin,
+        Float(arc4random()) / Float(UInt32.max),
+        Float(arc4random_uniform(32 - 3) + 3)
+      )
+    }
+
     lastCounter = SDL_GetPerformanceCounter()
 
     return .running
@@ -71,10 +73,22 @@ class Application {
   }
 
   private func paint(_ deltaTime: Float) -> ApplicationExecutionState {
+    balls.update(deltaTime)
+
     SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255)
     SDL_RenderClear(renderer)
 
     SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255)
+    for ball in balls.balls {
+      let position = ball.position(), size = ball.size()
+      var rect = SDL_FRect(
+        x: position.pointee.x - size,
+        y: position.pointee.y - size,
+        w: size * 2.0,
+        h: size * 2.0
+      )
+      SDL_RenderFillRect(renderer, &rect)
+    }
 
     SDL_RenderPresent(renderer)
     return .running

Sources/SwiftFrontend/CMakeLists.txt

@@ -1,5 +1,5 @@
 add_executable(SwiftFrontend MACOSX_BUNDLE main.swift Application.swift)
-target_link_libraries(SwiftFrontend PRIVATE SwiftBackend SDLSwift)
+target_link_libraries(SwiftFrontend PRIVATE CppBackend SDLSwift)
 set_target_properties(SwiftFrontend PROPERTIES
   XCODE_ATTRIBUTE_ENABLE_HARDENED_RUNTIME NO
   XCODE_EMBED_FRAMEWORKS "${SDL3}"