Extra2D/examples/scene_graph_demo/game_scene.cpp

#include "game_scene.h"
#include <cmath>

// ========================================
// PlayerNode 实现
// ========================================

PlayerNode::PlayerNode() {
  setName("Player");
  setTag(1);

  // 设置玩家尺寸
  setSize(64.0f, 64.0f);

  // 设置锚点为中心点
  setAnchor(0.5f, 0.5f);

  // 添加精灵渲染组件
  auto sprite = makePtr<SpriteRenderer>();
  sprite->setColor(Color::Blue);
  addComponent(sprite);
}

void PlayerNode::onUpdate(float dt) {
  time_ += dt;

  // 简单的圆周运动
  float radius = 200.0f;
  float x = 640.0f + radius * std::cos(time_ * 0.5f);
  float y = 360.0f + radius * std::sin(time_ * 0.5f);

  setPosition(x, y);

  // 根据移动方向旋转（顺时针，使用负角度）
  float angle = -time_ * 0.5f * 57.2958f + 90.0f;
  setRotation(angle);
}

// ========================================
// RotatingDecoration 实现
// ========================================

RotatingDecoration::RotatingDecoration() {
  setName("Decoration");

  // 设置尺寸
  setSize(32.0f, 32.0f);

  // 设置锚点为中心
  setAnchor(0.5f, 0.5f);

  // 添加精灵渲染组件
  auto sprite = makePtr<SpriteRenderer>();
  sprite->setColor(Color::Yellow);
  addComponent(sprite);
}

void RotatingDecoration::onUpdate(float dt) {
  // 自转（顺时针，使用负角度）
  setRotation(getRotation() - rotationSpeed_ * dt);
}

// ========================================
// GameScene 实现
// ========================================

GameScene::GameScene() {
  // 场景初始化
}

void GameScene::onEnter() {
  Scene::onEnter();

  // 创建相机
  createCamera();

  // 创建玩家
  createPlayer();

  // 创建装饰物
  createDecorations();
}

void GameScene::onExit() {
  // 清理资源
  player_.reset();
  decorations_.clear();

  Scene::onExit();
}


void GameScene::update(float dt) {
  Scene::update(dt);

  sceneTime_ += dt;

  // 更新玩家
  if (player_) {
    player_->onUpdate(dt);
  }

  // 更新装饰物
  for (auto &decoration : decorations_) {
    decoration->onUpdate(dt);
  }
}

void GameScene::createPlayer() {
  player_ = makePtr<PlayerNode>();
  player_->setPosition(640.0f, 360.0f);
  addChild(player_);
}

void GameScene::createDecorations() {
  // 创建围绕玩家旋转的装饰物
  int count = 8;
  float radius = 150.0f;

  for (int i = 0; i < count; ++i) {
    auto decoration = makePtr<RotatingDecoration>();

    // 计算位置（圆形分布）
    float angle = (2.0f * 3.14159f * i) / count;
    float x = 640.0f + radius * std::cos(angle);
    float y = 360.0f + radius * std::sin(angle);

    decoration->setPosition(x, y);
    decoration->setRotationSpeed(45.0f + i * 10.0f);

    // 设置不同颜色
    auto sprite = decoration->getComponent<SpriteRenderer>();
    if (sprite) {
      float hue = static_cast<float>(i) / count;
      // 简单的HSV到RGB转换
      float r = std::abs(hue * 6.0f - 3.0f) - 1.0f;
      float g = 2.0f - std::abs(hue * 6.0f - 2.0f);
      float b = 2.0f - std::abs(hue * 6.0f - 4.0f);
      sprite->setColor(Color(std::max(0.0f, std::min(1.0f, r)),
                             std::max(0.0f, std::min(1.0f, g)),
                             std::max(0.0f, std::min(1.0f, b)), 1.0f));
    }

    decorations_.push_back(decoration);
    addChild(decoration);
  }
}

void GameScene::createCamera() {
  // 创建相机节点
  auto cameraNode = makePtr<Node>();
  cameraNode->setName("MainCamera");
  // 相机位置在(0, 0)，这样世界坐标直接映射到屏幕
  cameraNode->setPosition(0.0f, 0.0f);

  // 添加相机组件
  auto camera = makePtr<CameraComponent>();
  // 使用标准的2D投影：左上角为(0, 0)，右下角为(1280, 720)
  // Y轴向下：bottom=720, top=0
  camera->setOrtho(0.0f, 1280.0f, 720.0f, 0.0f, -1.0f, 1.0f);
  cameraNode->addComponent(camera);

  // 设置为主相机
  setMainCamera(camera);

  // 添加相机节点到场景
  addChild(cameraNode);
}