chore(engine): switch to libGDX

For real

app/build.gradle.kts

@@ -5,6 +5,8 @@
  * For more details on building Java & JVM projects, please refer to https://docs.gradle.org/9.0.0/userguide/building_java_projects.html in the Gradle documentation.
  */
 
+val libgdxVersion = "1.13.5"
+
 plugins {
     // Apply the application plugin to add support for building a CLI application in Java.
     application
@@ -29,6 +31,27 @@ dependencies {
 
     // This dependency is used by the application.
     implementation(libs.guava)
+
+    // ----- LibGDX Core / Extras -----
+    implementation("com.badlogicgames.gdx:gdx:$libgdxVersion")
+    implementation("com.badlogicgames.gdx:gdx-box2d:$libgdxVersion")
+    implementation("com.badlogicgames.gdx:gdx-freetype:$libgdxVersion")
+    implementation("com.badlogicgames.ashley:ashley:1.7.4")
+
+    // ----- LibGDX Desktop (LWJGL3 + natives) -----
+    implementation("com.badlogicgames.gdx:gdx-backend-lwjgl3:$libgdxVersion")
+    implementation("com.badlogicgames.gdx:gdx-platform:$libgdxVersion:natives-desktop")
+    implementation("com.badlogicgames.gdx:gdx-box2d-platform:$libgdxVersion:natives-desktop")
+    implementation("com.badlogicgames.gdx:gdx-freetype-platform:$libgdxVersion:natives-desktop")
+
+    // Tools (exclude legacy LWJGL backend)
+    implementation("com.badlogicgames.gdx:gdx-tools:$libgdxVersion") {
+        exclude(group = "com.badlogicgames.gdx", module = "gdx-backend-lwjgl")
+    }
+
+    // Logging
+    implementation("org.slf4j:slf4j-api:2.1.0-alpha1")
+    implementation("ch.qos.logback:logback-classic:1.5.18")
 }
 
 // Apply a specific Java toolchain to ease working on different environments.
@@ -40,7 +63,12 @@ java {
 
 application {
     // Define the main class for the application.
-    mainClass = "org.vibecoders.moongazer.App"
+    mainClass = "org.vibecoders.moongazer.Main"
+}
+
+tasks.withType<JavaCompile>().configureEach {
+    options.encoding = "UTF-8"
+    options.release.set(23)
 }
 
 tasks.named<Test>("test") {

app/src/main/java/org/vibecoders/moongazer/App.java

@@ -1,25 +0,0 @@
-package org.vibecoders.moongazer;
-
-import javafx.application.Application;
-import javafx.scene.Scene;
-import javafx.scene.control.Label;
-import javafx.scene.layout.StackPane;
-import javafx.stage.Stage;
-
-public class App extends Application {
-
-    @Override
-    public void start(Stage stage) {
-        String javaVersion = System.getProperty("java.version");
-        String javafxVersion = System.getProperty("javafx.version");
-        Label l = new Label("Hello, JavaFX " + javafxVersion + ", running on Java " + javaVersion + ".");
-        Scene scene = new Scene(new StackPane(l), 640, 480);
-        stage.setScene(scene);
-        stage.show();
-    }
-
-    public static void main(String[] args) {
-        launch();
-    }
-
-}

app/src/main/java/org/vibecoders/moongazer/Constants.java

@@ -0,0 +1,15 @@
+package org.vibecoders.moongazer;
+
+/**
+ * Client configuration constants and default values
+ * used throughout the Moongazer client application.
+ */
+public class Constants {
+
+    /**
+     * Window configuration.
+     */
+    public static final int WINDOW_WIDTH = 1280;
+    public static final int WINDOW_HEIGHT = 720;
+    public static final String WINDOW_TITLE = "Moongazer";
+}

app/src/main/java/org/vibecoders/moongazer/Game.java

@@ -0,0 +1,29 @@
+package org.vibecoders.moongazer;
+
+import com.badlogic.gdx.ApplicationAdapter;
+import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.graphics.GL20;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import static org.vibecoders.moongazer.Constants.*;
+
+public class Game extends ApplicationAdapter {
+    private static final Logger log = LoggerFactory.getLogger(Game.class);
+
+    @Override
+    public void create() {
+        log.debug("create stub");
+    }
+
+    @Override
+    public void render() {
+        Gdx.gl.glClearColor(0, 0, 0, 1);
+        Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
+    }
+
+    @Override
+    public void dispose() {
+        log.debug("stub");
+    }
+}
+

app/src/main/java/org/vibecoders/moongazer/Main.java

@@ -0,0 +1,23 @@
+package org.vibecoders.moongazer;
+
+import com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application;
+import com.badlogic.gdx.backends.lwjgl3.Lwjgl3ApplicationConfiguration;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import static org.vibecoders.moongazer.Constants.*;
+
+public class Main {
+
+    private static final Logger log = LoggerFactory.getLogger(Main.class);
+
+    public static void main(String[] args) {
+        Lwjgl3ApplicationConfiguration cfg = new Lwjgl3ApplicationConfiguration();
+        cfg.setTitle(WINDOW_TITLE);
+        cfg.setWindowedMode(WINDOW_WIDTH, WINDOW_HEIGHT);
+        cfg.useVsync(true);
+        cfg.setIdleFPS(10);
+        cfg.setWindowIcon("icons/logo.png");
+        log.info("Starting game client");
+        new Lwjgl3Application(new Game(), cfg);
+    }
+}

gradle.properties

@@ -1,5 +1,5 @@
 # This file was generated by the Gradle 'init' task.
 # https://docs.gradle.org/current/userguide/build_environment.html#sec:gradle_configuration_properties
 
-org.gradle.configuration-cache=true
+org.gradle.configuration-cache=false