feat: add TextureManager class

src/graphics/texture/TextureManager.cpp

@@ -0,0 +1,81 @@
+#include "TextureManager.h"
+
+TextureManager::TextureManager(SDL_Renderer* renderer) :
+    m_renderer(renderer)
+{
+
+
+}
+
+TextureManager::~TextureManager() {
+    cleanupAllTexture();
+}
+
+
+void TextureManager::cleanupAllTexture() {
+
+    for (auto [id, texture] : m_cacheTexture) {
+        SDL_DestroyTexture(texture);
+    }
+
+    SDL_Log("TextureManager: cleanup all texture successful\n");
+
+}
+
+
+
+SDL_Texture* TextureManager::createTextureFromRect(int x, int y, SDL_FRect& rect, SDL_Color& color) {
+    
+    // 先在缓存中查找是否存在
+    auto it = getTexture(x, y);
+    if(it) {
+        return it;
+    }
+    if (!m_renderer) {
+        SDL_Log("TextureManager renderer is null\n");
+        return nullptr;
+    }
+    auto newTexture = SDL_CreateTexture(
+        m_renderer,
+        SDL_PIXELFORMAT_RGBA8888,
+        SDL_TEXTUREACCESS_TARGET,
+        rect.w,
+        rect.h
+    );
+    // 保存当前的渲染目标
+    auto currentTexture = SDL_GetRenderTarget(m_renderer);
+
+    SDL_SetRenderTarget(m_renderer, newTexture);
+    SDL_SetRenderDrawColor(m_renderer, color.r, color.g, color.b, color.a);
+    // 因为修改了渲染目标，所以坐标系不一样了
+    SDL_FRect renderRect = {0, 0, rect.w, rect.h};
+    SDL_RenderFillRect(m_renderer, &renderRect);
+
+    m_cacheTexture.emplace(makeHash(x, y), newTexture);
+
+    // 恢复渲染目标
+    SDL_SetRenderTarget(m_renderer, currentTexture);
+    return newTexture;
+}
+
+size_t TextureManager::makeHash(int x, int y) {
+    // 分别计算字体名称和大小的哈希值
+    size_t h1 = std::hash<int>{}(x);
+    size_t h2 = std::hash<int>{}(y);
+
+    // 组合两个哈希值：使用XOR运算和位左移组合两个独立的哈希值
+    // 这样可以确保不同的fontID或ptSize组合都会产生不同的哈希值
+    return h1 ^ (h2 << 1);
+}
+
+SDL_Texture* TextureManager::getTexture(int x, int y) {
+    auto key = makeHash(x, y);
+    auto it = m_cacheTexture.find(key);
+
+    if (it != m_cacheTexture.end()) {
+        return it->second;
+    } else {
+        SDL_Log("TextureManager: texture %d %d not exist!", x, y);
+        return nullptr;
+    }
+}

src/graphics/texture/TextureManager.h

@@ -0,0 +1,27 @@
+#pragma once
+#include <SDL3/SDL.h>
+#include <unordered_map>
+#include <string>
+
+class TextureManager {
+public:
+
+    TextureManager(SDL_Renderer* renderer);
+    ~TextureManager();
+
+
+    SDL_Texture* createTextureFromRect(int x, int y, SDL_FRect& rect, SDL_Color& coler);
+
+    void cleanupAllTexture();
+
+    SDL_Texture* getTexture(int x, int y);
+
+private:
+
+    SDL_Renderer* m_renderer = nullptr;
+
+    std::unordered_map<size_t, SDL_Texture*> m_cacheTexture;
+
+    size_t makeHash(int x, int y);
+
+};