Step 1: Create Project Directory Шаг 1: Создание директории проекта

Create a workspace folder and a new directory for your Box3D test project: Создайте рабочую папку для проектов и новую директорию для вашего тестового проекта Box3D:

Windows (Command Prompt / PowerShell)

mkdir C:\projects\box3d-test
cd C:\projects\box3d-test

Ubuntu (Terminal)

mkdir -p ~/projects/box3d-test
cd ~/projects/box3d-test

Step 2: Create Source Files (main.cpp & CMakeLists.txt) Шаг 2: Создание исходных файлов (main.cpp и CMakeLists.txt)

You can create these files using Notepad / Sublime Text on Windows, or nano in Ubuntu terminal: Вы можете создать эти файлы через Блокнот / Sublime Text в Windows или с помощью nano в терминале Ubuntu:

Windows (Terminal / Notepad)

notepad main.cpp
notepad CMakeLists.txt

Ubuntu (Terminal / Nano)

nano main.cpp
nano CMakeLists.txt

1. File Contents for main.cpp 1. Содержимое файла main.cpp

#include <box3d/box3d.h>
#include <iostream>

int main()
{
    std::cout << "Initializing Box3D physics world..." << std::endl;

    // Create world definition and set gravity
    b3WorldDef worldDef = b3DefaultWorldDef();
    worldDef.gravity = (b3Vec3) { 0.0f, -9.8f, 0.0f };

    // Create physics world
    b3WorldId worldId = b3CreateWorld(&worldDef);

    // Create ground static body
    b3BodyDef groundBodyDef = b3DefaultBodyDef();
    groundBodyDef.position = (b3Vec3) { 0.0f, -2.0f, 0.0f };
    b3BodyId groundId = b3CreateBody(worldId, &groundBodyDef);

    // Attach ground box shape
    b3BoxHull groundBox = b3MakeBoxHull(5.0f, 0.2f, 1.0f);
    b3ShapeDef groundShapeDef = b3DefaultShapeDef();
    b3CreateHullShape(groundId, &groundShapeDef, &groundBox.base);

    // Create dynamic falling body
    b3BodyDef boxBodyDef = b3DefaultBodyDef();
    boxBodyDef.type = b3_dynamicBody;
    boxBodyDef.position = (b3Vec3) { 0.0f, 5.0f, 0.0f };
    b3BodyId boxId = b3CreateBody(worldId, &boxBodyDef);

    // Attach dynamic box shape
    b3BoxHull boxHull = b3MakeBoxHull(0.5f, 0.5f, 0.5f);
    b3ShapeDef boxShapeDef = b3DefaultShapeDef();
    boxShapeDef.density = 1.0f;
    b3CreateHullShape(boxId, &boxShapeDef, &boxHull.base);

    // Prepare simulation parameters
    float timeStep = 1.0f / 60.0f;
    int subStepCount = 5;

    // Simulate 10 steps
    for (int i = 0; i < 10; ++i)
    {
        b3World_Step(worldId, timeStep, subStepCount);

        b3WorldTransform transform = b3Body_GetTransform(boxId);
        b3Vec3 position = b3ToVec3(transform.p);

        std::cout << "Step " << i + 1 << " -> Position: (" 
                  << position.x << ", " << position.y << ", " << position.z << ")" << std::endl;
    }

    // Clean up world
    b3DestroyWorld(worldId);

    std::cout << "Box3D simulation finished successfully!" << std::endl;
    return 0;
}

2. File Contents for CMakeLists.txt 2. Содержимое файла CMakeLists.txt

Imports Box3D static library target explicitly and configures platform-specific paths: Явно импортирует цель статической библиотеки Box3D и настраивает пути под платформу:

set(CMAKE_BUILD_TYPE "Debug")

cmake_minimum_required(VERSION 3.21)
project(box3d_test CXX)

set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

set(PROJECT_SOURCES
    main.cpp
)

add_executable(app)
target_sources(app PRIVATE ${PROJECT_SOURCES})

if(WIN32)
    set(BOX3D_DIR "C:/libs/box3d-0.1.0-mingw")

    target_include_directories(app PRIVATE
        ${BOX3D_DIR}/include
    )

    add_library(Box3D_Static STATIC IMPORTED)
    set_target_properties(Box3D_Static PROPERTIES
        IMPORTED_LOCATION "${BOX3D_DIR}/lib/libbox3d.a"
    )

    target_link_libraries(app PRIVATE
        Box3D_Static
    )

    # Strip symbols and optimize aggressive for size
    target_compile_options(app PRIVATE -Os)

    # MinGW static build settings
    target_link_options(app PRIVATE -static -s -static-libgcc -static-libstdc++)

    if (CMAKE_BUILD_TYPE STREQUAL "Debug")
        target_link_options(app PRIVATE -mconsole)
    else()
        target_link_options(app PRIVATE -mwindows)
    endif()

else() # Linux / Ubuntu
    set(BOX3D_DIR "$ENV{HOME}/libs/box3d-0.1.0-ubuntu")

    target_include_directories(app PRIVATE
        ${BOX3D_DIR}/include
    )

    add_library(Box3D_Static STATIC IMPORTED)
    set_target_properties(Box3D_Static PROPERTIES
        IMPORTED_LOCATION "${BOX3D_DIR}/lib/libbox3d.a"
    )

    find_package(Threads REQUIRED)

    target_link_libraries(app PRIVATE
        Box3D_Static
        Threads::Threads
    )
endif()

Step 3: Create Build & Execution Scripts Шаг 3: Создание скриптов сборки и запуска

Windows (MinGW / Batch Scripts)

config-exe.bat

cmake -G Ninja -S . -B dist/win

build-exe.bat

cmake --build dist/win

run-exe.bat

@echo off
.\dist\win\app.exe

Run the scripts sequentially in Command Prompt or PowerShell: Последовательно запустите скрипты в командной строке или PowerShell:

config-exe.bat
build-exe.bat
run-exe.bat

Ubuntu (Bash Scripts)

config-bin.sh

#!/usr/bin/env bash
set -e
cmake -G Ninja -S . -B dist/linux

build-bin.sh

#!/usr/bin/env bash
set -e
cmake --build dist/linux

run-bin.sh

#!/usr/bin/env bash
set -e
./dist/linux/app

Grant execute permissions on Ubuntu before running: Предоставьте права на выполнение в Ubuntu перед запуском:

chmod +x config-bin.sh build-bin.sh run-bin.sh
./config-bin.sh
./build-bin.sh
./run-bin.sh

Step 4: Expected Output Шаг 4: Ожидаемый результат

After running the build and execution scripts, you should see output similar to this: После запуска скриптов сборки и выполнения вы должны увидеть результат, похожий на следующий:

Initializing Box3D physics world...
Step 1 -> Position: (0, 4.99837, 0)
Step 2 -> Position: (0, 4.99401, 0)
Step 3 -> Position: (0, 4.98693, 0)
Step 4 -> Position: (0, 4.97713, 0)
Step 5 -> Position: (0, 4.96461, 0)
Step 6 -> Position: (0, 4.94937, 0)
Step 7 -> Position: (0, 4.9314, 0)
Step 8 -> Position: (0, 4.91071, 0)
Step 9 -> Position: (0, 4.8873, 0)
Step 10 -> Position: (0, 4.86117, 0)
Box3D simulation finished successfully!