refactor(渲染): 统一处理锚点计算逻辑

将锚点计算逻辑统一交由 RenderBackend 处理，简化各渲染组件的代码
添加窗口高级配置选项，支持自定义光标和DPI缩放
更新窗口初始化逻辑，使用配置中的宽高参数

Extra2D/include/extra2d/app/application.h

@@ -39,6 +39,9 @@ struct AppConfig {
   BackendType renderBackend = BackendType::OpenGL;
   int msaaSamples = 0;
   PlatformType platform = PlatformType::Auto;
+  // 窗口高级配置
+  bool enableCursors = true;        // 是否启用光标
+  bool enableDpiScale = false;      // 是否启用DPI缩放
 };
 
 // ============================================================================

Extra2D/src/animation/frame_renderer.cpp

@@ -155,9 +155,9 @@ void FrameRenderer::drawSpriteFrame(RenderBackend &renderer,
   float flipScaleX = flipX ? -1.0f : 1.0f;
   float flipScaleY = flipY ? -1.0f : 1.0f;
 
-  Rect destRect{
-      {finalPos.x - w * 0.5f * flipScaleX, finalPos.y - h * 0.5f * flipScaleY},
-      {w, h}};
+  // 锚点由 RenderBackend 在绘制时处理，这里只传递位置和尺寸
+  // 使用中心锚点(0.5, 0.5)，所以 destRect 从 finalPos 开始，不预偏移
+  Rect destRect{{finalPos.x, finalPos.y}, {w * flipScaleX, h * flipScaleY}};
 
   Color finalColor{tint.r, tint.g, tint.b, tint.a * opacity};
 

Extra2D/src/app/application.cpp

@@ -93,20 +93,20 @@ bool Application::init(const AppConfig &config) {
   window_ = makeUnique<Window>();
   WindowConfig winConfig;
   winConfig.title = config.title;
-  winConfig.width = 1280;
-  winConfig.height = 720;
+  winConfig.width = config.width;
+  winConfig.height = config.height;
   if (platform == PlatformType::Switch) {
     winConfig.fullscreen = true;
     winConfig.fullscreenDesktop = false;  // Switch 使用固定分辨率全屏
     winConfig.resizable = false;
-    winConfig.enableCursors = false;
-    winConfig.enableDpiScale = false;
+    winConfig.enableCursors = config.enableCursors;
+    winConfig.enableDpiScale = config.enableDpiScale;
   } else {
     // PC 平台默认窗口模式
     winConfig.fullscreen = config.fullscreen;
-    winConfig.resizable = true;
-    winConfig.enableCursors = true;
-    winConfig.enableDpiScale = true;
+    winConfig.resizable = config.resizable;
+    winConfig.enableCursors = config.enableCursors;
+    winConfig.enableDpiScale = config.enableDpiScale;
   }
   winConfig.vsync = config.vsync;
   winConfig.msaaSamples = config.msaaSamples;

Extra2D/src/effects/particle_system.cpp

@@ -121,9 +121,8 @@ void ParticleEmitter::render(RenderBackend &renderer) {
         continue;
 
       // 计算目标矩形
-      float halfSize = p.size * 0.5f;
-      Rect destRect(p.position.x - halfSize, p.position.y - halfSize, p.size,
-                    p.size);
+      // 锚点由 RenderBackend 在绘制时处理，这里只传递位置和尺寸
+      Rect destRect(p.position.x, p.position.y, p.size, p.size);
 
       renderer.drawSprite(
           *config_.texture, destRect,

Extra2D/src/scene/sprite.cpp

@@ -79,9 +79,8 @@ void Sprite::onDraw(RenderBackend &renderer) {
   auto pos = getPosition();
   auto anchor = getAnchor();
   auto scale = getScale();
-  Rect destRect(pos.x - width * anchor.x * scale.x,
-                pos.y - height * anchor.y * scale.y, width * scale.x,
-                height * scale.y);
+  // 锚点由 RenderBackend 在绘制时处理，这里只传递位置和尺寸
+  Rect destRect(pos.x, pos.y, width * scale.x, height * scale.y);
 
   // Adjust source rect for flipping
   Rect srcRect = textureRect_;
@@ -111,9 +110,8 @@ void Sprite::generateRenderCommand(std::vector<RenderCommand> &commands,
   auto pos = getPosition();
   auto anchor = getAnchor();
   auto scale = getScale();
-  Rect destRect(pos.x - width * anchor.x * scale.x,
-                pos.y - height * anchor.y * scale.y, width * scale.x,
-                height * scale.y);
+  // 锚点由 RenderBackend 在绘制时处理，这里只传递位置和尺寸
+  Rect destRect(pos.x, pos.y, width * scale.x, height * scale.y);
 
   // 调整源矩形（翻转）
   Rect srcRect = textureRect_;

xmake.lua

@@ -91,6 +91,7 @@ if is_config("examples","true") then
     includes("examples/spatial_index_demo", {rootdir = "examples/spatial_index_demo"})
     includes("examples/collision_demo", {rootdir = "examples/collision_demo"})
     includes("examples/push_box", {rootdir = "examples/push_box"})
+    -- includes("examples/flappy_bird", {rootdir = "examples/flappy_bird"})
 end
 
 -- ==============================================