Create API for pausing and stopping game engine

api/src/main/java/com/bartlomiejpluta/base/api/game/context/Context.java

@@ -27,6 +27,18 @@ public interface Context extends Updatable, Renderable, Disposable {
 
    GUI newGUI();
 
+   boolean isRunning();
+
+   void close();
+
+   boolean isPaused();
+
+   void pause();
+
+   void resume();
+
+   boolean togglePause();
+
    void init(Screen screen, Camera camera);
 
    void input(Screen screen);

engine/src/main/java/com/bartlomiejpluta/base/engine/core/engine/DefaultGameEngine.java

@@ -7,6 +7,7 @@ import com.bartlomiejpluta.base.engine.logic.GameLogic;
 import com.bartlomiejpluta.base.engine.thread.ThreadManager;
 import com.bartlomiejpluta.base.engine.time.ChronoMeter;
 import com.bartlomiejpluta.base.engine.ui.ScreenManager;
+import lombok.Getter;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -31,8 +32,12 @@ public class DefaultGameEngine implements GameEngine {
 
    private Context context;
 
+   @Getter
    private boolean running = false;
 
+   @Getter
+   private boolean paused = true;
+
    private void run() {
       try {
          init();
@@ -62,9 +67,13 @@ public class DefaultGameEngine implements GameEngine {
 
          input();
 
-         while (accumulator >= step) {
-            update(dt);
-            accumulator -= step;
+         if (!paused) {
+            while (accumulator >= step) {
+               update(dt);
+               accumulator -= step;
+            }
+         } else {
+            accumulator = 0;
          }
 
          render();
@@ -105,6 +114,33 @@ public class DefaultGameEngine implements GameEngine {
       thread.start();
    }
 
+   @Override
+   public void stop() {
+      log.info("Stopping the engine");
+      running = false;
+   }
+
+   @Override
+   public void pause() {
+      log.info("Pausing the engine");
+      paused = true;
+   }
+
+   @Override
+   public void resume() {
+      log.info("Resuming the engine");
+      paused = false;
+   }
+
+   @Override
+   public boolean togglePaused() {
+      paused = !paused;
+
+      log.info("{} the engine", paused ? "Pausing" : "Resuming");
+
+      return paused;
+   }
+
    // TODO
    // It is supposed to be moved to the Context so that
    // user will be able to choose default window size,

engine/src/main/java/com/bartlomiejpluta/base/engine/core/engine/GameEngine.java

@@ -4,4 +4,16 @@ import com.bartlomiejpluta.base.api.game.context.Context;
 
 public interface GameEngine {
    void start(Context context);
+
+   void stop();
+
+   void pause();
+
+   void resume();
+
+   boolean isRunning();
+
+   boolean isPaused();
+
+   boolean togglePaused();
 }

engine/src/main/java/com/bartlomiejpluta/base/engine/project/model/DefaultContext.java

@@ -101,6 +101,36 @@ public class DefaultContext implements Context {
       return gui;
    }
 
+   @Override
+   public boolean isRunning() {
+      return engine.isRunning();
+   }
+
+   @Override
+   public void close() {
+      engine.stop();
+   }
+
+   @Override
+   public boolean isPaused() {
+      return engine.isPaused();
+   }
+
+   @Override
+   public void pause() {
+      engine.pause();
+   }
+
+   @Override
+   public void resume() {
+      engine.resume();
+   }
+
+   @Override
+   public boolean togglePause() {
+      return engine.togglePaused();
+   }
+
    @Override
    public void input(Screen screen) {
       gameRunner.input(screen);

engine/src/main/java/com/bartlomiejpluta/base/engine/ui/GLFWScreen.java

@@ -81,13 +81,6 @@ public class GLFWScreen implements Screen {
          GLFWScreen.this.size.y = height;
       });
 
-      // Setup a key callback. It will be called every time a key is pressed, repeated or released.
-      glfwSetKeyCallback(windowHandle, (window, key, scancode, action, mods) -> {
-         if (key == GLFW_KEY_ESCAPE && action == GLFW_RELEASE) {
-            glfwSetWindowShouldClose(window, true); // We will detect this in the rendering loop
-         }
-      });
-
       // Get the resolution of the primary monitor
       GLFWVidMode videoMode = glfwGetVideoMode(glfwGetPrimaryMonitor());