Scene

Scene

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• Example
• Settings
• How to set up a Scene
  • Populate the Scene

A Scene is the engine of the library. It handles all the objects and updating stuff.

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Scene hirarchy The picture shows the Hirarchy of Objects inside a Scene. The topmost GameObjects in the tree hirarchy are called the root objects.
Update loop The Scene is updaded using a QTimer, the update loop is shown in the picture.

Example

#include <QApplication>
#include "QSFML_EditorWidget.h"

int main(int argc, char* argv[])
{
    QApplication app(argc, argv);

    QSFML::SceneSettings settings;
    QSFML::Scene scene(nullptr, settings);

    scene.addObject(new QSFML::Objects::DefaultEditor());

    scene.start();
    return app.exec();
}

Settings

#include <QApplication>
#include "QSFML_EditorWidget.h"

int main(int argc, char* argv[])
{
    QApplication app(argc, argv);

    QSFML::SceneSettings settings;

    // Background color of parts on which nothing was painted
    settings.colors.defaultBackground = sf::Color(80, 80, 80);

    // sf::ContextSettings for the render window
    settings.contextSettings.antialiasingLevel = 8;

    // QLayout margin for when the Scene has a QWidget parent
    settings.layout.margin.left = 6;
    settings.layout.margin.top = 6;
    settings.layout.margin.right = 6;
    settings.layout.margin.bottom = 6;

    settings.layout.autoAjustSize = true; // If set to true, the Scene will automatically resizes based on its parent widget.
    settings.layout.fixedSize = sf::Vector2u(1000, 700); // If autoAjustSize is false, this size will be applyed to the Scene widget

    settings.timing.frameTime = 0.01;           // Target time between frames in seconds
    settings.timing.physicsDeltaTScale = 0.1;   // Scale factor for delta time, returned from GameObject::getDeltaT() 
    settings.timing.physicsFixedDeltaT = 0.01;  // Delta time for the fixed physics calculation. GameObject::getFixedDeltaT()

    // Enable or disable the different loops
    settings.updateControlls.enableEventLoop = true;
    settings.updateControlls.enablePaintLoop = true;
    settings.updateControlls.enableUpdateLoop = true;

    // Enable or disable multithreading for the update loop
    settings.updateControlls.enableMultithreading = false;
    QSFML::Scene scene(nullptr, settings);
    
    scene.addObject(new QSFML::Objects::DefaultEditor());

    scene.start();
    return app.exec();
}

How to set up a Scene

Its recommended to use a Scene inside a QMainWindow The example below shows how the scene is set up inside a QMainWindow.

ExampleScene.cpp

ExampleScene.h

#include "ExampleScene.h" #include "ui_exampleScene.h" #include <iostream> #include <QCloseEvent> #include <QDebug> using namespace QSFML; using namespace QSFML::Objects; ExampleScene::ExampleScene(QWidget *parent) : QMainWindow(parent) , ui(new Ui::ExampleScene) { ui->setupUi(this); setupScene(); } ExampleScene::~ExampleScene() { delete ui; delete m_scene; } void ExampleScene::setupScene() { SceneSettings settings; settings.contextSettings.antialiasingLevel = 8; settings.timing.frameTime = 0.02; m_scene = new Scene(ui->SceneWidget, settings); // Create Objects and add them to the Scene DefaultEditor* defaultEditor = new DefaultEditor(); m_scene->addObject(defaultEditor); m_scene->start(); } void ExampleScene::closeEvent(QCloseEvent* event) { if (m_scene) m_scene->stop(); event->accept(); }

#pragma once #include <QMainWindow> #include "QSFML_EditorWidget.h" QT_BEGIN_NAMESPACE namespace Ui { class ExampleScene; } QT_END_NAMESPACE class ExampleScene : public QMainWindow { Q_OBJECT public: ExampleScene(QWidget* parent = nullptr); ~ExampleScene(); private: void setupScene(); void closeEvent(QCloseEvent* event) override; Ui::ExampleScene* ui; QSFML::Scene* m_scene = nullptr; };

void ExampleScene::setupScene()
{
    SceneSettings settings;
    settings.contextSettings.antialiasingLevel = 8;
    settings.timing.frameTime = 0.02;
    m_scene = new Scene(ui->SceneWidget, settings);

    DefaultEditor* defaultEditor = new DefaultEditor();
    m_scene->addObject(defaultEditor);
    m_scene->start();
}

Use any QWidget inside the window as a parent for the scene. In this case ui->SceneWidget is used as the parent widget.
The Scene will automaticly create a layout inside that parent widget and inserts its main camera to that widget.

Populate the Scene

void ExampleScene::setupScene()
{
    SceneSettings settings;
    m_scene = new Scene(ui->SceneWidget, settings);

    // Creates the background grid and enables the camera movement
    DefaultEditor* defaultEditor = new DefaultEditor();
    
    // Creating custom GameObjects
    Car* car = new Car();

    // Add the GameObjects to the scene
    m_scene->addObject(defaultEditor);
    m_scene->addObject(car);

    m_scene->start();
}

Create the GameObjects on the heap, the lifetime of the objects is handled by the Scene, as long as they belong to a Scene.
Add all objects to the Scene using: m_scene->addObject(obj);