Add monitor API and add UUIDs

graphics/glfw/src/main/java/de/staropensource/sosengine/graphics/glfw/classes/GlfwInternalClass.java

@@ -0,0 +1,69 @@
+/*
+ * STAROPENSOURCE ENGINE SOURCE FILE
+ * Copyright (c) 2024 The StarOpenSource Engine Contributors
+ * Licensed under the GNU Affero General Public License v3
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.staropensource.sosengine.graphics.glfw.classes;
+
+import de.staropensource.sosengine.base.logging.Logger;
+import de.staropensource.sosengine.base.types.CodePart;
+import de.staropensource.sosengine.base.types.logging.LogIssuer;
+import de.staropensource.sosengine.graphics.classes.Monitor;
+import de.staropensource.sosengine.graphics.classes.api.ApiInternalClass;
+import de.staropensource.sosengine.graphics.exceptions.NoMonitorsFoundException;
+import org.jetbrains.annotations.NotNull;
+import org.lwjgl.PointerBuffer;
+
+import java.lang.reflect.InvocationTargetException;
+import java.util.LinkedHashSet;
+
+import static org.lwjgl.glfw.GLFW.*;
+
+@SuppressWarnings({ "unused" })
+public abstract class GlfwInternalClass implements ApiInternalClass {
+    /**
+     * Returns the {@link Monitor} class.
+     *
+     * @return {@link Monitor} class
+     * @since v1-alpha2
+     */
+    @NotNull
+    public abstract Class<? extends Monitor> getMonitorClass();
+
+    /**
+     * Returns all connected monitors.
+     *
+     * @return connected monitors
+     * @since v1-alpha2
+     */
+    @Override
+    public @NotNull LinkedHashSet<@NotNull Monitor> getMonitors() throws NoMonitorsFoundException {
+        PointerBuffer monitors = glfwGetMonitors();
+        LinkedHashSet<@NotNull Monitor> output = new LinkedHashSet<>();
+        if (monitors == null)
+            throw new NoMonitorsFoundException();
+
+        while (monitors.hasRemaining())
+            try {
+                output.add(getMonitorClass().getDeclaredConstructor(Long.TYPE).newInstance(monitors.get()));
+            } catch (NoSuchMethodException | InstantiationException | IllegalAccessException | InvocationTargetException exception) {
+                Logger.crash(new LogIssuer(getClass(), CodePart.ENGINE), "Unable to create new Monitor instance: Threw an exception", exception);
+            }
+
+        return output;
+    }
+}

graphics/glfw/src/main/java/de/staropensource/sosengine/graphics/glfw/classes/GlfwManagementClass.java

@@ -58,6 +58,7 @@ public abstract class GlfwManagementClass extends ApiManagementClass {
 
         LinkedHashMap<@NotNull Window, @NotNull Throwable> throwables = new LinkedHashMap<>();
 
+        // Update and render all windows
         for (Window window : Window.getWindows()) {
             try {
                 window.updateState();
@@ -67,6 +68,8 @@ public abstract class GlfwManagementClass extends ApiManagementClass {
                 throwables.put(window, throwable);
             }
         }
+
+        // Poll for events
         glfwPollEvents();
 
         return throwables;

graphics/glfw/src/main/java/de/staropensource/sosengine/graphics/glfw/classes/GlfwMonitor.java

@@ -0,0 +1,114 @@
+/*
+ * STAROPENSOURCE ENGINE SOURCE FILE
+ * Copyright (c) 2024 The StarOpenSource Engine Contributors
+ * Licensed under the GNU Affero General Public License v3
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.staropensource.sosengine.graphics.glfw.classes;
+
+import de.staropensource.sosengine.base.types.vectors.Vec2i;
+import de.staropensource.sosengine.graphics.classes.Monitor;
+import de.staropensource.sosengine.graphics.exceptions.InvalidMonitorException;
+import lombok.SneakyThrows;
+import org.jetbrains.annotations.NotNull;
+import org.lwjgl.glfw.GLFWVidMode;
+
+import java.util.Objects;
+
+import static org.lwjgl.glfw.GLFW.*;
+
+@SuppressWarnings({ "unused", "JavadocDeclaration", "JavadocBlankLines" })
+public class GlfwMonitor extends Monitor {
+    /**
+     * Contains the {@link #identifier} as a long.
+     *
+     * @since v1-alpha2
+     *
+     * -- GETTER --
+     * Returns the monitor identifier as a long.
+     *
+     * @return monitor identifier as a long
+     * @since v1-alpha2
+     */
+    private final long identifierLong;
+
+    /**
+     * Constructs this class.
+     *
+     * @param identifier glfw monitor pointer
+     * @since v1-alpha2
+     */
+    @SneakyThrows
+    public GlfwMonitor(long identifier) throws InvalidMonitorException {
+        // Set identifier
+        setIdentifier(String.valueOf(identifier));
+        identifierLong = identifier;
+
+        // Check if connected
+        checkConnected();
+    }
+
+    /** {@inheritDoc} */
+    @SneakyThrows
+    public void checkConnected() throws InvalidMonitorException {
+        super.checkConnected();
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public boolean isConnected() {
+        return glfwGetMonitorName(identifierLong) != null;
+    }
+
+    /**
+     * Returns the monitor name.
+     *
+     * @return monitor name
+     * @since v1-alpha2
+     */
+    @Override
+    public @NotNull String getName() throws InvalidMonitorException {
+        checkConnected();
+        return Objects.requireNonNull(glfwGetMonitorName(identifierLong));
+    }
+
+    /**
+     * Returns the monitor size.
+     *
+     * @return monitor size
+     * @since v1-alpha2
+     */
+    @Override
+    public @NotNull Vec2i getSize() throws InvalidMonitorException {
+        checkConnected();
+
+        GLFWVidMode videoMode = Objects.requireNonNull(glfwGetVideoMode(identifierLong));
+
+        return new Vec2i(videoMode.width(), videoMode.height());
+    }
+
+    /**
+     * Returns the monitor refresh rate.
+     *
+     * @return monitor refresh rate
+     * @since v1-alpha2
+     */
+    @Override
+    public short getRefreshRate() throws InvalidMonitorException {
+        checkConnected();
+        return (short) Objects.requireNonNull(glfwGetVideoMode(identifierLong)).refreshRate();
+    }
+}

graphics/glfw/src/main/java/de/staropensource/sosengine/graphics/glfw/classes/GlfwWindow.java

@@ -24,6 +24,7 @@ import de.staropensource.sosengine.base.types.Tristate;
 import de.staropensource.sosengine.base.types.vectors.Vec2i;
 import de.staropensource.sosengine.base.utility.Miscellaneous;
 import de.staropensource.sosengine.graphics.GraphicsSubsystemConfiguration;
+import de.staropensource.sosengine.graphics.classes.Monitor;
 import de.staropensource.sosengine.graphics.classes.Window;
 import de.staropensource.sosengine.graphics.events.GraphicsApiErrorEvent;
 import de.staropensource.sosengine.graphics.events.InputEvent;
@@ -41,6 +42,7 @@ import org.lwjgl.system.MemoryStack;
 import org.lwjgl.system.MemoryUtil;
 
 import java.nio.IntBuffer;
+import java.util.Objects;
 
 import static org.lwjgl.glfw.GLFW.*;
 
@@ -90,6 +92,7 @@ public abstract class GlfwWindow extends Window {
      * @param maximumSize maximum size
      * @param position    position
      * @param windowMode  window mode
+     * @param monitor     monitor
      * @param resizable   resizable flag
      * @param borderless  borderless flag
      * @param focusable   focusable flag
@@ -99,8 +102,8 @@ public abstract class GlfwWindow extends Window {
      * @throws UnexpectedThrowableException stuff thrown by the {@link #initializeWindow()} and {@link #render()} methods of the implementing Graphics API
      * @since v1-alpha2
      */
-    public GlfwWindow(@NotNull String name, @NotNull String title, @NotNull Vec2i size, @NotNull Vec2i minimumSize, @NotNull Vec2i maximumSize, @NotNull Vec2i position, @NotNull WindowMode windowMode, boolean resizable, boolean borderless, boolean focusable, boolean onTop, boolean transparent, boolean rendering) throws UnexpectedThrowableException {
+    public GlfwWindow(@NotNull String name, @NotNull String title, @NotNull Vec2i size, @NotNull Vec2i minimumSize, @NotNull Vec2i maximumSize, @NotNull Vec2i position, @NotNull WindowMode windowMode, @NotNull Monitor monitor, boolean resizable, boolean borderless, boolean focusable, boolean onTop, boolean transparent, boolean rendering) throws UnexpectedThrowableException {
-        super(name, title, size, minimumSize, maximumSize, position, windowMode, resizable, borderless, focusable, onTop, transparent, rendering);
+        super(name, title, size, minimumSize, maximumSize, position, windowMode, monitor, resizable, borderless, focusable, onTop, transparent, rendering);
     }
 
     /** {@inheritDoc} */
@@ -226,6 +229,31 @@ public abstract class GlfwWindow extends Window {
         if (!Miscellaneous.onMainThread())
             throw new NotOnMainThreadException();
 
+        // Update window mode
+        if (Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_ICONIFIED)))
+            super.setWindowMode(WindowMode.MINIMIZED);
+        else if (Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_MAXIMIZED)))
+            super.setWindowMode(WindowMode.MAXIMIZED);
+        else if (Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_VISIBLE)))
+            super.setWindowMode(WindowMode.WINDOWED);
+        else if (Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_VISIBLE)))
+            super.setWindowMode(WindowMode.HIDDEN);
+
+        // Update monitor
+        if (!getMonitor().isConnected()) {
+            Monitor newMonitor = null;
+
+            for (Monitor monitor : Monitor.getMonitors())
+                if (monitor.isConnected())
+                    newMonitor = monitor;
+
+            if (newMonitor == null)
+                getLogger().crash("Unable to set a new target monitor for window " + getUniqueIdentifier() + " as no monitors are connected to the system");
+
+            setMonitor(Objects.requireNonNull(newMonitor));
+        }
+
+        // Update vectors
         try (MemoryStack stack = MemoryStack.stackPush()) {
             IntBuffer width = stack.mallocInt(2);
             IntBuffer height = stack.mallocInt(2);
@@ -237,16 +265,6 @@ public abstract class GlfwWindow extends Window {
             super.setPosition(new Vec2i(width.get(), height.get()));
         }
 
-        // Update window mode
-        if (Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_ICONIFIED)))
-            super.setWindowMode(WindowMode.MINIMIZED);
-        else if (Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_MAXIMIZED)))
-            super.setWindowMode(WindowMode.MAXIMIZED);
-        else if (Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_VISIBLE)))
-            super.setWindowMode(WindowMode.WINDOWED);
-        else if (Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_VISIBLE)))
-            super.setWindowMode(WindowMode.HIDDEN);
-
         // Update booleans
         super.setResizable(Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_RESIZABLE)));
         super.setOnTop(Miscellaneous.getBooleanizedInteger(glfwGetWindowAttrib(identifierLong, GLFW_FLOATING)));

graphics/opengl/src/main/java/de/staropensource/sosengine/graphics/opengl/OpenGlInternalApi.java

@@ -19,16 +19,27 @@
 
 package de.staropensource.sosengine.graphics.opengl;
 
+import de.staropensource.sosengine.graphics.classes.Monitor;
 import de.staropensource.sosengine.graphics.classes.api.ApiInternalClass;
 import de.staropensource.sosengine.graphics.classes.Window;
+import de.staropensource.sosengine.graphics.glfw.classes.GlfwInternalClass;
+import de.staropensource.sosengine.graphics.opengl.classes.OpenGlMonitor;
 import de.staropensource.sosengine.graphics.opengl.classes.OpenGlWindow;
 import org.jetbrains.annotations.NotNull;
 
-public final class OpenGlInternalApi implements ApiInternalClass {
+import java.util.Set;
+
+public final class OpenGlInternalApi extends GlfwInternalClass {
     /** {@inheritDoc} */
     @Override
     @NotNull
     public Class<? extends Window> getWindowClass() {
         return OpenGlWindow.class;
     }
+
+    /** {@inheritDoc} */
+    @Override
+    public @NotNull Class<? extends Monitor> getMonitorClass() {
+        return OpenGlMonitor.class;
+    }
 }

graphics/opengl/src/main/java/de/staropensource/sosengine/graphics/opengl/classes/OpenGlMonitor.java

@@ -0,0 +1,35 @@
+/*
+ * STAROPENSOURCE ENGINE SOURCE FILE
+ * Copyright (c) 2024 The StarOpenSource Engine Contributors
+ * Licensed under the GNU Affero General Public License v3
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.staropensource.sosengine.graphics.opengl.classes;
+
+import de.staropensource.sosengine.graphics.exceptions.InvalidMonitorException;
+import de.staropensource.sosengine.graphics.glfw.classes.GlfwMonitor;
+
+public class OpenGlMonitor extends GlfwMonitor {
+    /**
+     * Constructs this class.
+     *
+     * @param identifier glfw monitor pointer
+     * @since v1-alpha2
+     */
+    public OpenGlMonitor(long identifier) throws InvalidMonitorException {
+        super(identifier);
+    }
+}

graphics/opengl/src/main/java/de/staropensource/sosengine/graphics/opengl/classes/OpenGlWindow.java

@@ -21,6 +21,7 @@ package de.staropensource.sosengine.graphics.opengl.classes;
 
 import de.staropensource.sosengine.base.exceptions.UnexpectedThrowableException;
 import de.staropensource.sosengine.base.types.vectors.Vec2i;
+import de.staropensource.sosengine.graphics.classes.Monitor;
 import de.staropensource.sosengine.graphics.glfw.classes.GlfwWindow;
 import de.staropensource.sosengine.graphics.exceptions.NotOnMainThreadException;
 import de.staropensource.sosengine.graphics.exceptions.WindowCreationFailureException;
@@ -57,8 +58,8 @@ public final class OpenGlWindow extends GlfwWindow {
      * @throws UnexpectedThrowableException stuff thrown by the {@link #initializeWindow()} and {@link #render()} methods of the implementing Graphics API
      * @since v1-alpha2
      */
-    public OpenGlWindow(@NotNull String name, @NotNull String title, @NotNull Vec2i size, @NotNull Vec2i minimumSize, @NotNull Vec2i maximumSize, @NotNull Vec2i position, @NotNull WindowMode windowMode, boolean resizable, boolean borderless, boolean focusable, boolean onTop, boolean transparent, boolean rendering) throws UnexpectedThrowableException {
+    public OpenGlWindow(@NotNull String name, @NotNull String title, @NotNull Vec2i size, @NotNull Vec2i minimumSize, @NotNull Vec2i maximumSize, @NotNull Vec2i position, @NotNull WindowMode windowMode, @NotNull Monitor monitor, boolean resizable, boolean borderless, boolean focusable, boolean onTop, boolean transparent, boolean rendering) throws UnexpectedThrowableException {
-        super(name, title, size, minimumSize, maximumSize, position, windowMode, resizable, borderless, focusable, onTop, transparent, rendering);
+        super(name, title, size, minimumSize, maximumSize, position, windowMode, monitor, resizable, borderless, focusable, onTop, transparent, rendering);
     }
 
     /** {@inheritDoc} */

graphics/src/main/java/de/staropensource/sosengine/graphics/classes/Monitor.java

@@ -0,0 +1,171 @@
+/*
+ * STAROPENSOURCE ENGINE SOURCE FILE
+ * Copyright (c) 2024 The StarOpenSource Engine Contributors
+ * Licensed under the GNU Affero General Public License v3
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.staropensource.sosengine.graphics.classes;
+
+import de.staropensource.sosengine.base.logging.LoggerInstance;
+import de.staropensource.sosengine.base.types.CodePart;
+import de.staropensource.sosengine.base.types.logging.LogIssuer;
+import de.staropensource.sosengine.base.types.vectors.Vec2i;
+import de.staropensource.sosengine.graphics.GraphicsSubsystem;
+import de.staropensource.sosengine.graphics.exceptions.InvalidMonitorException;
+import de.staropensource.sosengine.graphics.exceptions.NoMonitorsFoundException;
+import lombok.AccessLevel;
+import lombok.Getter;
+import lombok.Setter;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.LinkedHashSet;
+import java.util.UUID;
+
+/**
+ * Abstract class for implementing monitors in a Graphics API.
+ * <p>
+ * Note that monitors stop working unannounced when disconnected,
+ * call {@link #isConnected()} before using to avoid unexpected behaviour.
+ *
+ * @since v1-alpha2
+ */
+@SuppressWarnings({ "unused", "JavadocDeclaration", "JavadocBlankLines" })
+public abstract class Monitor {
+    /**
+     * The logger instance for this class.
+     *
+     * @see LoggerInstance
+     * @since v1-alpha2
+     *
+     * -- GETTER --
+     * Returns the logger instance for this class.
+     *
+     * @return logger instance
+     * @see LoggerInstance
+     * @since v1-alpha2
+     */
+    @Getter(value = AccessLevel.PROTECTED)
+    private final LoggerInstance logger = new LoggerInstance(new LogIssuer(getClass(), CodePart.ENGINE));
+
+    /**
+     * Contains the unique monitor identifier.
+     * <p>
+     * This identifier is unique to every monitor and does not change during runtime.
+     *
+     * @since v1-alpha2
+     *
+     * -- GETTER --
+     * Returns the unique monitor identifier.
+     * <p>
+     * This identifier is unique to every monitor and does not change during runtime.
+     *
+     * @return unique identifier
+     * @since v1-alpha2
+     */
+    @Getter
+    private final UUID uniqueIdentifier;
+
+    /**
+     * Contains the monitor identifier.
+     * <p>
+     * This identifier is used by the Graphics API to refer to a monitor and may change during runtime.
+     *
+     * @since v1-alpha1
+     *
+     * -- GETTER --
+     * Returns the monitor identifier.
+     * <p>
+     * This identifier is used by the Graphics API to refer to a monitor and may change during runtime.
+     *
+     * @return monitor identifier
+     * @since v1-alpha2
+     *
+     * -- SETTER --
+     * Sets the monitor identifier.
+     * <p>
+     * This identifier is used by the Graphics API to refer to a monitor and may change during runtime.
+     *
+     * @param identifier new monitor identifier
+     * @since v1-alpha2
+     */
+    @Setter(AccessLevel.PROTECTED)
+    private String identifier = null;
+
+    /**
+     * Constructs this class.
+     *
+     * @since v1-alpha2
+     */
+    public Monitor() {
+        this.uniqueIdentifier = UUID.randomUUID();
+    }
+
+    /**
+     * Returns all connected monitors.
+     *
+     * @return connected monitors
+     * @since v1-alpha2
+     */
+    @NotNull
+    public static LinkedHashSet<@NotNull Monitor> getMonitors() throws NoMonitorsFoundException {
+        return GraphicsSubsystem.getInstance().getApi().getInternalApi().getMonitors();
+    }
+
+    /**
+     * Checks if the monitor is actually connected.
+     * If not, throws an {@link InvalidMonitorException}.
+     *
+     * @since v1-alpha2
+     */
+    public void checkConnected() throws InvalidMonitorException, NoMonitorsFoundException {
+        if (!isConnected())
+            throw new InvalidMonitorException();
+    }
+
+    /**
+     * Checks if the monitor is connected or not.
+     *
+     * @return connection status
+     * @since v1-alpha2
+     */
+    public abstract boolean isConnected() throws NoMonitorsFoundException;
+
+    /**
+     * Returns the monitor name.
+     *
+     * @return monitor name
+     * @since v1-alpha2
+     */
+    @NotNull
+    public abstract String getName() throws InvalidMonitorException, NoMonitorsFoundException;
+
+    /**
+     * Returns the monitor size.
+     *
+     * @return monitor size
+     * @since v1-alpha2
+     */
+    @NotNull
+    public abstract Vec2i getSize() throws InvalidMonitorException, NoMonitorsFoundException;
+
+    /**
+     * Returns the monitor refresh rate.
+     *
+     * @return monitor refresh rate
+     * @since v1-alpha2
+     */
+    public abstract short getRefreshRate() throws InvalidMonitorException, NoMonitorsFoundException;
+}

graphics/src/main/java/de/staropensource/sosengine/graphics/classes/Window.java

@@ -35,6 +35,7 @@ import org.jetbrains.annotations.Nullable;
 
 import java.util.HashSet;
 import java.util.Set;
+import java.util.UUID;
 
 /**
  * Abstract class for implementing windows in a Graphics API.
@@ -94,13 +95,34 @@ public abstract class Window implements AutoCloseable {
     @Setter(AccessLevel.PROTECTED)
     private boolean terminated;
 
+    /**
+     * Contains the unique window identifier.
+     * <p>
+     * This identifier is unique to every window and does not change during runtime.
+     *
+     * @since v1-alpha2
+     *
+     * -- GETTER --
+     * Returns the unique window identifier.
+     * <p>
+     * This identifier is unique to every window and does not change during runtime.
+     *
+     * @return unique identifier
+     * @since v1-alpha2
+     */
+    private final UUID uniqueIdentifier;
+
     /**
      * Contains the window identifier.
+     * <p>
+     * This identifier is used by the Graphics API to refer to a window and may change during runtime.
      *
      * @since v1-alpha1
      *
      * -- GETTER --
      * Returns the window identifier.
+     * <p>
+     * This identifier is used by the Graphics API to refer to a window and may change during runtime.
      *
      * @return window identifier
      * @since v1-alpha2
@@ -108,7 +130,7 @@ public abstract class Window implements AutoCloseable {
      * -- SETTER --
      * Sets the window identifier.
      * <p>
-     * Recommended to be called only once.
+     * This identifier is used by the Graphics API to refer to a window and may change during runtime.
      *
      * @param identifier new window identifier
      * @since v1-alpha2
@@ -317,6 +339,27 @@ public abstract class Window implements AutoCloseable {
     @Setter
     private WindowMode windowMode;
 
+    /**
+     * Determines on which {@link Monitor} the window is displayed on.
+     *
+     * @since v1-alpha2
+     *
+     * -- GETTER --
+     * Returns the {@link Monitor} the window is displayed on.
+     *
+     * @return target monitor
+     * @since v1-alpha2
+     *
+     * -- SETTER --
+     * Sets the {@link Monitor} the window is displayed on.
+     *
+     * @param monitor new target monitor
+     * @since v1-alpha2
+     */
+    @NotNull
+    @Setter
+    private Monitor monitor;
+
     /**
      * Determines how fast the window may update it's contents.
      *
@@ -485,6 +528,7 @@ public abstract class Window implements AutoCloseable {
      * @param maximumSize maximum size
      * @param position    position
      * @param windowMode  window mode
+     * @param monitor     monitor
      * @param resizable   resizable flag
      * @param borderless  borderless flag
      * @param focusable   focusable flag
@@ -494,10 +538,9 @@ public abstract class Window implements AutoCloseable {
      * @throws UnexpectedThrowableException stuff thrown by the {@link #initializeWindow()} and {@link #render()} methods of the implementing Graphics API
      * @since v1-alpha2
      */
-    public Window(@NotNull String name, @NotNull String title, @NotNull Vec2i size, @NotNull Vec2i minimumSize, @NotNull Vec2i maximumSize, @NotNull Vec2i position, @NotNull WindowMode windowMode, boolean resizable, boolean borderless, boolean focusable, boolean onTop, boolean transparent, boolean rendering) throws UnexpectedThrowableException {
+    public Window(@NotNull String name, @NotNull String title, @NotNull Vec2i size, @NotNull Vec2i minimumSize, @NotNull Vec2i maximumSize, @NotNull Vec2i position, @NotNull WindowMode windowMode, @NotNull Monitor monitor, boolean resizable, boolean borderless, boolean focusable, boolean onTop, boolean transparent, boolean rendering) throws UnexpectedThrowableException {
-        logger.diag("Creating new window with properties: name=\"" + name + "\" title=\"" + title + "\" size=" + size + " minimumSize=" + minimumSize + " maximumSize=" + maximumSize + " position=" + position + " windowMode=" + windowMode + " resizable=" + resizable + " borderless=" + borderless + " focusable=" + focusable + " onTop=" + onTop + " transparent=" + transparent + " rendering=" + rendering);
-
         // Initialize variables
+        this.uniqueIdentifier = UUID.randomUUID();
         this.name = name;
         this.title = title;
         this.size = size;
@@ -505,6 +548,7 @@ public abstract class Window implements AutoCloseable {
         this.maximumSize = maximumSize;
         this.position = position;
         this.windowMode = windowMode;
+        this.monitor = monitor;
         this.resizable = resizable;
         this.borderless = borderless;
         this.focusable = focusable;
@@ -512,6 +556,9 @@ public abstract class Window implements AutoCloseable {
         this.transparent = transparent;
         this.rendering = rendering;
 
+        // Log about window creation
+        logger.diag("Creating new window with properties: uniqueIdentifier=" + uniqueIdentifier + " name=\"" + name + "\" title=\"" + title + "\" size=" + size + " minimumSize=" + minimumSize + " maximumSize=" + maximumSize + " position=" + position + " windowMode=" + windowMode + " monitor=" + monitor.getUniqueIdentifier() + " (" + monitor.getName() + ") resizable=" + resizable + " borderless=" + borderless + " focusable=" + focusable + " onTop=" + onTop + " transparent=" + transparent + " rendering=" + rendering);
+
         try {
             // Allow Graphics API to initialize window
             initializeWindow();
@@ -752,6 +799,22 @@ public abstract class Window implements AutoCloseable {
         @Nullable
         private WindowMode windowMode = null;
 
+        /**
+         * Contains the target monitor.
+         *
+         * @see Window#monitor
+         * @since v1-alpha2
+         *
+         * -- GETTER --
+         * Returns the target monitor.
+         *
+         * @return target monitor
+         * @see Window#monitor
+         * @since v1-alpha2
+         */
+        @Nullable
+        private Monitor monitor = null;
+
         /**
          * Contains the resizable flag.
          *
@@ -888,6 +951,8 @@ public abstract class Window implements AutoCloseable {
                 maximumSize = new Vec2i(-1, -1);
             if (windowMode == null)
                 windowMode = WindowMode.WINDOWED;
+            if (monitor == null)
+                monitor = Monitor.getMonitors().getFirst();
 
             // Override booleanized tristate defaults
             if (resizable == Tristate.FALSE)
@@ -906,8 +971,8 @@ public abstract class Window implements AutoCloseable {
             // Create new Window instance
             try {
                 return GraphicsSubsystem.getInstance().getApi().getInternalApi().getWindowClass()
-                        .getDeclaredConstructor(String.class, String.class, Vec2i.class, Vec2i.class, Vec2i.class, Vec2i.class, WindowMode.class, Boolean.TYPE, Boolean.TYPE, Boolean.TYPE, Boolean.TYPE, Boolean.TYPE, Boolean.TYPE)
+                        .getDeclaredConstructor(String.class, String.class, Vec2i.class, Vec2i.class, Vec2i.class, Vec2i.class, WindowMode.class, Monitor.class, Boolean.TYPE, Boolean.TYPE, Boolean.TYPE, Boolean.TYPE, Boolean.TYPE, Boolean.TYPE)
-                        .newInstance(name, title, size, minimumSize, maximumSize, position, windowMode, resizableBoolean, borderlessBoolean, focusableBoolean, onTopBoolean, transparentBoolean, renderingBoolean);
+                        .newInstance(name, title, size, minimumSize, maximumSize, position, windowMode, monitor, resizableBoolean, borderlessBoolean, focusableBoolean, onTopBoolean, transparentBoolean, renderingBoolean);
             } catch (Throwable throwable) {
                 throw new UnexpectedThrowableException(throwable, "Window.Builder was unable to create new Window instance");
             }
@@ -1004,6 +1069,19 @@ public abstract class Window implements AutoCloseable {
             return this;
         }
 
+        /**
+         * Sets the target monitor.
+         *
+         * @param monitor new target monitor
+         * @return builder instance
+         * @since v1-alpha2
+         */
+        @NotNull
+        private synchronized Builder setMonitor(@Nullable Monitor monitor) {
+            this.monitor = monitor;
+            return this;
+        }
+
         /**
          * Sets the resizable flag.
          *

graphics/src/main/java/de/staropensource/sosengine/graphics/classes/api/ApiInternalClass.java

@@ -19,9 +19,13 @@
 
 package de.staropensource.sosengine.graphics.classes.api;
 
+import de.staropensource.sosengine.graphics.classes.Monitor;
 import de.staropensource.sosengine.graphics.classes.Window;
+import de.staropensource.sosengine.graphics.exceptions.NoMonitorsFoundException;
 import org.jetbrains.annotations.NotNull;
 
+import java.util.LinkedHashSet;
+
 /**
  * The interface for internal API access, used by the graphics subsystem.
  *
@@ -33,7 +37,17 @@ public interface ApiInternalClass {
      * Returns the {@link Window} class.
      *
      * @return {@link Window} class
+     * @since v1-alpha2
      */
     @NotNull
     Class<? extends Window> getWindowClass();
+
+    /**
+     * Returns all connected monitors.
+     *
+     * @return connected monitors
+     * @since v1-alpha2
+     */
+    @NotNull
+    LinkedHashSet<@NotNull Monitor> getMonitors() throws NoMonitorsFoundException;
 }

graphics/src/main/java/de/staropensource/sosengine/graphics/events/InputEvent.java

@@ -64,7 +64,8 @@ public class InputEvent implements Event {
      */
     public void callEvent(@Nullable Window window, @NotNull Key key, @NotNull KeyState state) {
         if (GraphicsSubsystemConfiguration.getInstance().isDebugInput())
-            logger.diag("Got input event: window=" + (window == null ? "<null>" : window.getName() + (window.getName() == null ? "" : "(" + window.getName() + ")") + "[" + window.hashCode() + "]") + " key=" + key.name() + " state=" + state.name());
+            logger.diag("Got input event: window=" + (window == null ? "\\<null>" : window.getUniqueIdentifier()) + " key=" + key.name() + " state=" + state.name());
+
         EventHelper.invokeAnnotatedMethods(getClass(), window, key, state);
     }
 }

graphics/src/main/java/de/staropensource/sosengine/graphics/exceptions/InvalidMonitorException.java

@@ -0,0 +1,27 @@
+/*
+ * STAROPENSOURCE ENGINE SOURCE FILE
+ * Copyright (c) 2024 The StarOpenSource Engine Contributors
+ * Licensed under the GNU Affero General Public License v3
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.staropensource.sosengine.graphics.exceptions;
+
+/**
+ * Thrown when the specified monitor could not be found.
+ *
+ * @since v1-alpha2
+ */
+public class InvalidMonitorException extends RuntimeException {}

graphics/src/main/java/de/staropensource/sosengine/graphics/exceptions/NoMonitorsFoundException.java

@@ -25,4 +25,4 @@ package de.staropensource.sosengine.graphics.exceptions;
  * @since v1-alpha2
  */
 @SuppressWarnings({ "unused" })
-public final class NoMonitorsFoundException extends Exception {}
+public final class NoMonitorsFoundException extends RuntimeException {}