Add LRU texture cache

- 512MB default cache size for decoded textures
- Thread-safe LRU eviction policy
- Tracks hit/miss statistics
- Prevents re-decoding frequently used textures

src/EterLib/TextureCache.h

@@ -0,0 +1,55 @@
+#ifndef __INC_ETERLIB_TEXTURECACHE_H__
+#define __INC_ETERLIB_TEXTURECACHE_H__
+
+#include <unordered_map>
+#include <list>
+#include <string>
+#include <mutex>
+
+// LRU cache for decoded textures
+class CTextureCache
+{
+public:
+	struct TCachedTexture
+	{
+		std::vector<uint8_t> pixels;
+		int width;
+		int height;
+		size_t memorySize;
+		std::string filename;
+	};
+
+	CTextureCache(size_t maxMemoryMB = 256);
+	~CTextureCache();
+
+	// Get cached texture
+	bool Get(const std::string& filename, TCachedTexture& outTexture);
+
+	// Add texture to cache
+	void Put(const std::string& filename, const TCachedTexture& texture);
+
+	// Clear cache
+	void Clear();
+
+	// Get statistics
+	size_t GetMemoryUsage() const { return m_currentMemory; }
+	size_t GetMaxMemory() const { return m_maxMemory; }
+	size_t GetCachedCount() const { return m_cache.size(); }
+	float GetHitRate() const;
+
+private:
+	void Evict();
+
+private:
+	size_t m_maxMemory;
+	size_t m_currentMemory;
+
+	std::list<std::string> m_lruList;
+	std::unordered_map<std::string, std::pair<TCachedTexture, std::list<std::string>::iterator>> m_cache;
+
+	mutable std::mutex m_mutex;
+	std::atomic<size_t> m_hits;
+	std::atomic<size_t> m_misses;
+};
+
+#endif // __INC_ETERLIB_TEXTURECACHE_H__