Ray Collision Example

Test Colission on a Quad object

        ...
        Geometry plane = new Geometry("quad", new Quad(size, size));
        Material planeMat = new Material(assetManager, "Common/MatDefs/Misc/Unshaded.j3md");
        planeMat.setColor("Color", ColorRGBA.Blue);
        planeMat.getAdditionalRenderState().setWireframe(true);
        plane.setMaterial(planeMat);
        plane.center().move(pos);
        rootNode.attachChild(plane);
        ...


private ActionListener shootActionListener = new ActionListener() {

        public void onAction(String name, boolean keyPressed, float tpf) {
            if (name.equals("Shoot") && !keyPressed) {
                // 1. Reset results list.
                CollisionResults results = new CollisionResults();
                // 2. Aim the ray from cam loc to cam direction.
                Ray ray = new Ray(cam.getLocation(), cam.getDirection());
                // 3. Collect intersections between Ray and Shootables in results list.
                rootNode.getChild("quad").collideWith(ray, results);
                // 4. Print the results
                System.out.println("----- Collisions: " + results.size() + "-----");
                for (int i = 0; i < results.size(); i++) {
                    // For each hit, we know distance, impact point, name of geometry.
                    float dist = results.getCollision(i).getDistance();
                    Vector3f pt = results.getCollision(i).getContactPoint();
                    String hit = results.getCollision(i).getGeometry().getName();
                    System.out.println("* Collision #" + i);
                    System.out.println("  You shot " + hit + " at " + pt + ", " + dist + " wu away.");
                }
                // 5. Use the results (we mark the hit object)
                if (results.size() > 0) {
                    // The closest collision point is what was truly hit:
                    CollisionResult closest = results.getClosestCollision();
                    // Let's interact - we mark the hit with a red dot.
                    mark.setLocalTranslation(closest.getContactPoint());
                    rootNode.attachChild(mark);
                } else {
                    // No hits? Then remove the red mark.
                    rootNode.detachChild(mark);
                }
            }
        }
    };