package lecture16;

import com.jme3.app.SimpleApplication;
import com.jme3.light.DirectionalLight;
import com.jme3.material.Material;
import com.jme3.math.ColorRGBA;
import com.jme3.math.Vector3f;
import com.jme3.scene.Geometry;
import com.jme3.scene.shape.Sphere;

public class Example04 extends SimpleApplication {
    // world constants

    final float g = 9.8f;
    final Vector3f gravity = new Vector3f(0, -g, 0);
    // distance to travel
    final float distance = 100f;
    // how fast along the x axis. Play with this value!
    final float vx = 80f;
    Geometry bullet;
    Geometry target;
    Vector3f velocity = new Vector3f(0, 0, 0);
    Vector3f acceleration = new Vector3f(0, 0, 0);

    private Geometry makeBall(ColorRGBA color) {
        Material mat = new Material(assetManager, "Common/MatDefs/Light/Lighting.j3md");
        mat.setBoolean("UseMaterialColors", true);
        mat.setColor("Ambient", color);
        mat.setColor("Diffuse", color);

        Sphere s = new Sphere(60, 60, 1.5f);
        Geometry geom = new Geometry("Sphere", s);
        geom.setMaterial(mat);
        return geom;
    }

    public void simpleInitApp() {
        DirectionalLight sun = new DirectionalLight();
        sun.setDirection(new Vector3f(-10, 2, -2).normalize());
        sun.setColor(ColorRGBA.White);
        rootNode.addLight(sun);

        bullet = makeBall(ColorRGBA.Blue);
        rootNode.attachChild(bullet);

        target = makeBall(ColorRGBA.Red);
        rootNode.attachChild(target);

        target.move(distance, 0, 0);


        float vy = (g * distance) / (2 * vx);
        velocity = new Vector3f(vx, vy, 0);

        cam.setLocation(new Vector3f(distance + 15, 0, 15));
        cam.lookAt(new Vector3f(3 * distance / 4f, 0, 0), Vector3f.UNIT_Y);


    }

    @Override
    public void simpleUpdate(float tpf) {
        if (bullet.getLocalTranslation().getY() >= 0) {
            velocity = velocity.add(gravity.mult(tpf));
            bullet.move(velocity.mult(tpf));
        }

    }

    public static void main(String[] args) {
        Example04 app = new Example04();
        app.start();
    }
}