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Flyweight Pattern

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The Flyweight design pattern is a structural pattern designed to minimize memory usage by sharing as much data as possible with other similar objects. It divides an object's data into two categories: intrinsic state(heavy, constant, and shareable data) and extrinsic state (lightweight, unique, context-specific data) #include <iostream> #include <string> #include <string_view> #include <unordered_map> #include <vector> #include <memory> #include <shared_mutex> // 1. INTRINSIC STATE (The Flyweight) // This class contains heavy, immutable data shared across thousands of instances. class TreeModel { public: TreeModel(std::string name, std::string color, std::vector texture_data) : name_(std::move(name)), color_(std::move(color)), texture_bytes_(std::move(texture_data)) { std::cout texture_bytes_; // Simulates heavy mesh/texture data }; // 2. FLYWEIGHT FACTORY // Manages the shared pool of flyweights. It ensures obje...
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Design Patterns

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Creational: Factory Method (class) Abstract Factory (object) Builder  (object) Prototype  (object) Singleton  (object) Structral: Adapter (class/object) Bridge (object) Composite (object) Decorator  (object) Facade  (object) Flyweight   (object) Proxy  (object) Behavioral: Interpreter (class) Template Method (class) Chain of Responsibility (object) Command (object) Iterator (object) Mediator (object) Memento (object) Observer (object) State (object) Strategy (object) Visitor (object)
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Adding Chinese watermarks to images using ffmpeg on Windows 10

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Code: ffmpeg -i i1.jpg -vf "drawtext=text='仅为开户使用':fontfile='C\:/Windows/Fonts/msyh.ttc':fontsize=168:fontcolor=white@0.5:x=(w-text_w)/2:y=(h-text_h)/2" output.jpg Multi Line Version: ffmpeg -i i1.jpg -vf "drawtext=text='仅为开户使用':fontfile='C\:/Windows/Fonts/msyh.ttc':fontsize=w*0.03:fontcolor=white@0.7:x=w*0.1:y=h*0.2,drawtext=text='仅为开户使用':fontfile='C\:/Windows/Fonts/msyh.ttc':fontsize=w*0.03:fontcolor=white@0.7:x=w*0.4:y=h*0.2,drawtext=text='仅为开户使用':fontfile='C\:/Windows/Fonts/msyh.ttc':fontsize=w*0.03:fontcolor=white@0.7:x=w*0.7:y=h*0.2,drawtext=text='仅为开户使用':fontfile='C\:/Windows/Fonts/msyh.ttc':fontsize=w*0.03:fontcolor=white@0.7:x=w*0.1:y=h*0.5,drawtext=text='仅为开户使用':fontfile='C\:/Windows/Fonts/msyh.ttc':fontsize=w*0.03:fontcolor=white@0.7:x=w*0.4:y=h*0.5,drawtext=text='仅为开户使用':fontfile='C\:/Windows/Fonts/msyh.ttc':fontsize=w*0.03:fontcolor=white@0.7:x...
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Using spdlog in a C++ project

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Tree structure of the project. The code of main.cc. #include <iostream> #include "spdlog/spdlog.h" #include "spdlog/sinks/basic_file_sink.h" #include "spdlog/sinks/rotating_file_sink.h" void do_work_in_another_file(); void rotating_example() { try { // Create a file rotating logger with 5 MB size max and 3 rotated files auto max_size = 1048576 * 5; auto max_files = 3; // Set output time pattern // %f: Time accurate to microseconds // %n: Output mode "some_logger_name" // %l: Prints the severity level of the log message. Example include info, warn, error, debug or critical. // %v: Prints the actual text or payload of the log message that you passed to the function. spdlog::set_pattern("[%Y-%m-%d %H:%M:%S.%f] [%n] [%l] %v"); // Set it as default so you can spdlog::info() directly. auto logger = spdlog::rotating_logger_mt("som...
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vim的智能配置

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" 显示行号 set number " 将Tab键自动转换为空格 set expandtab " 设置Tab键本身的宽度为4个空格 set tabstop=4 " 设置按退格键(BackSpace)时一次删除4个空格 set softtabstop=4 " 设置使用>或<进行缩进时的宽度为4个空格 set shiftwidth=4 " 开启自动缩进(新行继承上一行的缩进) set autoindent " 开启C/C++语言智能缩进 set cindent " 搜索优化 set incsearch set ignorecase " 语法高亮 syntax on " 开启256色支持(在终端使用时非常重要) set t_Co=256
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Installing vim via msys2 and config vim on windows10

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1. Installing vim Open msys2 ucrt64 terminal and enter command as follows: ``` pacman -S vim ``` 2. Configure vim Open msys2 ucrt64 terminal and enter command as follows: ``` cd ~ touch .vimrc ``` Adding the content into .vimrc which you want to. For example: ``` set number ```
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Constructing C++ Projects via CMake on Windows in git bash

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1. Installing CMake CMake Download 2. Building Source Code Files hello.cc #include <iostream> #include "spdlog/spdlog.h" int main(void) { spdlog::info("Welcome to spdlog!"); std::cout << "Hello World!" << std::endl; return 0; } 3. Building CMakeLists.txt File # 指定CMake最低版本 cmake_minimum_required(VERSION 3.10) # 必须在项目名称前指定C++编译器 set (CMAKE_CXX_COMPILER "g++.exe") # 指定项目名称和使用的编程语言 project(MyProject LANGUAGES CXX) # 添加spdlog目录,让spdlog可用 add_subdirectory(third_party/spdlog) # 指定C++标准 set(CMAKE_CXX_STANDARD 11) set(CMAKE_CXX_STANDARD_REQUIRED True) # 指定生成的可执行文件及对应的源文件 add_executable(my_app main.cc) # 使用spdlog头文件模式 target_link_libraries(my_app PRIVATE spdlog::spdlog_header_only) 4. Building Project # 1. 配置项目（生成 Makefile 或 Ninja 文件） # -G "MinGW Makefiles" 指定使用MinGW而不是Windows默认的nmake, # 当然要提前安装MinGW到C:/MinGW安装路径不要有空格否则可能报错 # 且C:/MinGW/bin要放到Windows的环境路径上 # -G Ninja 指定使用Ninja，同样Ninja也需要提前准备好 #...
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