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Fostbite2D/include/fostbite2D/render/opengl/gl_texture.h

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+#pragma once
+
+#include <fostbite2D/core/color.h>
+#include <fostbite2D/core/types.h>
+#include <fostbite2D/render/texture.h>
+
+#include <glad/glad.h>
+
+#include <memory>
+#include <string>
+
+namespace frostbite2D {
+
+// ============================================================================
+// OpenGL 纹理实现
+// ============================================================================
+class GLTexture : public Texture {
+public:
+  GLTexture(int width, int height, const uint8_t *pixels, int channels);
+  GLTexture(const std::string &filepath);
+  ~GLTexture();
+
+  // Texture 接口实现
+  int getWidth() const override { return width_; }
+  int getHeight() const override { return height_; }
+  Size getSize() const override {
+    return Size(static_cast<float>(width_), static_cast<float>(height_));
+  }
+  int getChannels() const override { return channels_; }
+  PixelFormat getFormat() const override;
+  void *getNativeHandle() const override {
+    return reinterpret_cast<void *>(static_cast<uintptr_t>(textureID_));
+  }
+  bool isValid() const override { return textureID_ != 0; }
+  void setFilter(bool linear) override;
+  void setWrap(bool repeat) override;
+
+  // 从参数创建纹理的工厂方法
+  static Ptr<Texture> create(int width, int height, PixelFormat format);
+
+  // 加载压缩纹理（KTX/DDS 格式）
+  bool loadCompressed(const std::string &filepath);
+
+  // OpenGL 特定
+  GLuint getTextureID() const { return textureID_; }
+  void bind(unsigned int slot = 0) const;
+  void unbind() const;
+
+  // 获取纹理数据大小（字节），用于 VRAM 跟踪
+  size_t getDataSize() const { return dataSize_; }
+
+  // Alpha 遮罩
+  bool hasAlphaMask() const {
+    return alphaMask_ != nullptr && alphaMask_->isValid();
+  }
+  const AlphaMask *getAlphaMask() const { return alphaMask_.get(); }
+  void generateAlphaMask(); // 从当前纹理数据生成遮罩
+
+private:
+  GLuint textureID_;
+  int width_;
+  int height_;
+  int channels_;
+  PixelFormat format_;
+  size_t dataSize_;
+
+  // 原始像素数据（用于生成遮罩）
+  std::vector<uint8_t> pixelData_;
+  std::unique_ptr<AlphaMask> alphaMask_;
+
+  void createTexture(const uint8_t *pixels);
+
+  // KTX 文件加载
+  bool loadKTX(const std::string &filepath);
+  // DDS 文件加载
+  bool loadDDS(const std::string &filepath);
+};
+
+} // namespace frostbite2D