Jumping Sphere Example - Jmonkeyengine Typing CST Test
Loading…
Jumping Sphere Example — Jmonkeyengine Code
A sphere jumps up and falls down simulating gravity.
import com.jme3.app.SimpleApplication;
import com.jme3.scene.Geometry;
import com.jme3.scene.shape.Sphere;
import com.jme3.material.Material;
import com.jme3.math.ColorRGBA;
public class JumpingSphereApp extends SimpleApplication {
private Geometry sphere;
private float vy = 0;
private float y = 1;
private float gravity = -9.8f;
public static void main(String[] args) {
new JumpingSphereApp().start();
}
@Override
public void simpleInitApp() {
Sphere s = new Sphere(16,16,1);
sphere = new Geometry("Sphere", s);
Material mat = new Material(assetManager, "Common/MatDefs/Misc/Unshaded.j3md");
mat.setColor("Color", ColorRGBA.Green);
sphere.setMaterial(mat);
sphere.setLocalTranslation(0,y,0);
rootNode.attachChild(sphere);
}
@Override
public void simpleUpdate(float tpf) {
vy += gravity * tpf;
y += vy * tpf;
if (y < 1) { y = 1; vy = 5; } // bounce
sphere.setLocalTranslation(0, y, 0);
}
}Jmonkeyengine Language Guide
jMonkeyEngine (jME) is an open-source, cross-platform 3D game engine written in Java. It allows developers to create 3D games and interactive applications with full control over rendering, physics, and scene management.
Primary Use Cases
- ▸3D PC games
- ▸Android 3D games
- ▸Educational simulations
- ▸Virtual reality prototypes
- ▸Interactive 3D visualizations
Notable Features
- ▸Java-based development
- ▸Cross-platform deployment (desktop, Android, Web via WebGL)
- ▸Scene graph architecture
- ▸Bullet Physics integration
- ▸Shader support (GLSL/HLSL via OpenGL)
Origin & Creator
jMonkeyEngine was created in 2003 by Mark Powell and a group of open-source contributors to provide a Java-based 3D game engine for hobbyists and developers.
Industrial Note
jME is popular among Java developers seeking a full-featured 3D engine with a scene graph system, built-in physics, and a flexible rendering pipeline, particularly for desktop and Android targets.
Quick Explain
- ▸jMonkeyEngine uses Java and supports desktop, Android, and web (via WebGL) platforms.
- ▸It provides a scene graph architecture, built-in physics (Bullet Physics), shader support, and tools for 3D asset management.
- ▸Used by indie developers, educational institutions, and hobbyists for 3D game development and simulations.
Core Features
- ▸Scene graph and spatial objects
- ▸3D model loading (OBJ, glTF, etc.)
- ▸Camera and lighting control
- ▸Physics and collision system
- ▸Audio, input, and GUI integration
Learning Path
- ▸Learn Java and OOP principles
- ▸Understand scene graph architecture
- ▸Practice physics integration
- ▸Implement custom shaders and lighting
- ▸Deploy to desktop and Android
Practical Examples
- ▸3D first-person shooter
- ▸Physics-based puzzle game
- ▸Virtual reality prototype
- ▸3D racing game
- ▸Interactive 3D visualization
Comparisons
- ▸jME vs Unity: Java code-centric vs editor-based
- ▸jME vs MonoGame: Java 3D vs C# 2D/3D
- ▸jME vs Godot: Java 3D vs GUI-friendly multi-language
- ▸jME vs Unreal: lightweight Java engine vs AAA engine
- ▸jME vs LibGDX: full 3D engine vs 2D/3D hybrid framework
Strengths
- ▸Full-featured 3D engine in Java
- ▸Open-source and free
- ▸Integrated physics and shader support
- ▸Active developer community
- ▸Cross-platform for desktop and mobile
Limitations
- ▸Primarily 3D; 2D support is minimal
- ▸Requires good understanding of Java and OOP
- ▸No visual editor included by default (SceneComposer optional)
- ▸Smaller asset marketplace than Unity or Unreal
- ▸Limited built-in networking; third-party needed for multiplayer
When NOT to Use
- ▸2D-only casual games
- ▸Rapid drag-and-drop prototyping
- ▸AAA visual fidelity projects
- ▸Projects needing extensive asset marketplace
- ▸Non-Java developers
Cheat Sheet
- ▸SimpleApplication = main class
- ▸Node = container object
- ▸Spatial = 3D object
- ▸Control = attach behavior
- ▸AppState = modular game logic
FAQ
- ▸Is jMonkeyEngine free?
- ▸Yes - fully open-source.
- ▸Does it support 2D?
- ▸Minimal; mainly 3D engine.
- ▸Which platforms are supported?
- ▸Windows, macOS, Linux, Android, Web (WebGL).
- ▸Is it beginner-friendly?
- ▸Moderate; requires Java knowledge.
- ▸Does it have visual editor?
- ▸Optional SceneComposer; core engine is code-driven.
30-Day Skill Plan
- ▸Week 1: Java basics and Hello jME
- ▸Week 2: Scene graph and Spatials
- ▸Week 3: Physics and collision handling
- ▸Week 4: Shaders, lighting, and post-processing
- ▸Week 5: Cross-platform builds and optimization
Final Summary
- ▸jMonkeyEngine is a Java-based 3D game engine with scene graph architecture and integrated physics.
- ▸It supports desktop, Android, and WebGL deployment.
- ▸Best suited for Java developers creating 3D games, simulations, and interactive applications.
- ▸Offers flexibility, open-source community support, and robust rendering and physics systems.
- ▸Less suitable for 2D-only projects or rapid drag-and-drop prototyping.
Project Structure
- ▸Main.java - entry point
- ▸Assets/ - models, textures, sounds
- ▸AppStates/ - game logic modules
- ▸Controls/ - object behaviors
- ▸Shaders/ - custom rendering shaders
Monetization
- ▸Paid PC/Android games
- ▸In-app purchases via Android
- ▸Educational software licensing
- ▸Ad integrations via Android SDK
- ▸VR/AR commercial applications
Productivity Tips
- ▸Leverage SceneComposer for faster setup
- ▸Reuse Controls and AppStates
- ▸Profile performance early
- ▸Use Level-of-Detail (LOD) for models
- ▸Batch static geometries
Basic Concepts
- ▸Scene graph: hierarchical object structure
- ▸Spatial: basic 3D object
- ▸Node: container for Spatials
- ▸Control: attach behavior to objects
- ▸AppState: modular game/application logic