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// most applications will want to extend the SimpleGame class import com.jme.app.SimpleGame; // a vector containing three float numbers; // used to store positions and translations import com.jme.math.Vector3f; import com.jme.math.Quaternion; import com.jme.math.Matrix3f; // geometric shapes used in program import com.jme.scene.shape.Box; import com.jme.scene.shape.Sphere; // use predefined colors and create custom colors import com.jme.renderer.ColorRGBA; // work with basic materials import com.jme.scene.state.MaterialState; // process user input import com.jme.input.InputHandler; import com.jme.input.KeyInput; import com.jme.input.KeyBindingManager; import com.jme.input.FirstPersonHandler; // an internal vertex of the scenegraph tree; // use to group together objects, // apply render settings, which affects all child vertices import com.jme.scene.Node; import com.jme.scene.Spatial; import com.jme.scene.Geometry; // methods to change render settings import com.jme.renderer.Renderer; // collision import com.jme.bounding.*; import com.jme.intersection.*; /** * Collide */ public class CollideDemo extends SimpleGame { // geometric shapes to be rendered Sphere mySphere; Sphere leftSphere; Sphere rightSphere; Box floorBox; // used in collision detection BoundingCollisionResults myCollisionList = new BoundingCollisionResults(); CollisionData myCollision; Spatial targetHit; int numCollisions = 0; Vector3f lastPosition = new Vector3f(); public static void main(String[] args) { // create an instance of this program CollideDemo app = new CollideDemo(); // before the main program starts, display the graphics configuration window // where the user can choose among screen resolution, color depth, and full screen options app.setConfigShowMode(ConfigShowMode.AlwaysShow); // The start() method runs simpleInitGame(), // then starts the game loop: simpleUpdate(), then simpleRender() // To terminate game loop, call finish() app.start(); } protected void simpleInitGame() { // make the standard cursor visible. org.lwjgl.input.Mouse.setGrabbed(false); // SimpleGame class defaults mouse behavior to rotate view; here we disable this. ((FirstPersonHandler)input).getMouseLookHandler().setEnabled(false); // create a material to apply to geometric objects, use objects' default color, // apply to front and back, and assign rendering to root node MaterialState customMaterial = display.getRenderer().createMaterialState(); customMaterial.setColorMaterial(MaterialState.ColorMaterial.AmbientAndDiffuse); customMaterial.setMaterialFace(MaterialState.MaterialFace.FrontAndBack); rootNode.setRenderState(customMaterial); mySphere = new Sphere("mySphere", new Vector3f(0,0,0), 30, 30, 1 ); mySphere.setSolidColor( ColorRGBA.yellow ); mySphere.setModelBound(new BoundingSphere()); mySphere.updateModelBound(); rootNode.attachChild( mySphere ); leftSphere = new Sphere("lefty", new Vector3f(-3,0,0), 30, 30, 1 ); leftSphere.setSolidColor( ColorRGBA.red ); leftSphere.setModelBound(new BoundingSphere()); leftSphere.updateModelBound(); rootNode.attachChild( leftSphere ); rightSphere = new Sphere("righty", new Vector3f(3,0,0), 30, 30, 1 ); rightSphere.setSolidColor( ColorRGBA.blue ); rightSphere.setModelBound(new BoundingSphere()); rightSphere.updateModelBound(); rootNode.attachChild( rightSphere ); floorBox = new Box("wally", new Vector3f(0,-3,0), 1, 1, 1); floorBox.setSolidColor( ColorRGBA.magenta ); floorBox.setModelBound(new OrientedBoundingBox()); floorBox.updateModelBound(); rootNode.attachChild( floorBox ); buildInput(); } protected void simpleUpdate() { try { Thread.sleep(1000/120); } // force decrease in frames per second catch (Exception e) { } processInput(); processCollisions(); } protected void simpleRender() { // nothing to add } // create input bindings public void buildInput() { // remove all pre-existing key assignments KeyBindingManager.getKeyBindingManager().removeAll(); // exit the program KeyBindingManager.getKeyBindingManager().set( "exit", KeyInput.KEY_ESCAPE ); KeyBindingManager.getKeyBindingManager().set( "toggle_wire", KeyInput.KEY_F1 ); KeyBindingManager.getKeyBindingManager().set( "toggle_bounds", KeyInput.KEY_F2 ); KeyBindingManager.getKeyBindingManager().set( "nodeTranslateX+", KeyInput.KEY_D ); KeyBindingManager.getKeyBindingManager().set( "nodeTranslateX-", KeyInput.KEY_A ); KeyBindingManager.getKeyBindingManager().set( "nodeTranslateY+", KeyInput.KEY_W ); KeyBindingManager.getKeyBindingManager().set( "nodeTranslateY-", KeyInput.KEY_S ); } // process input entered since last update. public void processInput() { // defining speed in terms of tpf (time per frame) helps keep speed constant // across varying framerates float speed = 2*tpf; // used for collision with solid walls Quaternion oldRotation = mySphere.getLocalRotation().clone(); Vector3f oldPosition = mySphere.getLocalTranslation().clone(); if (KeyBindingManager.getKeyBindingManager().isValidCommand("nodeTranslateX+", true)) mySphere.getLocalTranslation().addLocal(speed,0,0); // alternatively, we could write // myBox.getLocalTranslation().addLocal( Vector3f.UNIT_X.mult(speed) ); if (KeyBindingManager.getKeyBindingManager().isValidCommand("nodeTranslateX-", true)) mySphere.getLocalTranslation().addLocal(-speed,0,0); if (KeyBindingManager.getKeyBindingManager().isValidCommand("nodeTranslateY+", true)) mySphere.getLocalTranslation().addLocal(0,speed,0); if (KeyBindingManager.getKeyBindingManager().isValidCommand("nodeTranslateY-", true)) mySphere.getLocalTranslation().addLocal(0,-speed,0); // COLLISION DETECTION - WALLS // next line needed, for otherwise we will be using old data for collision detection, // which is bad mySphere.updateGeometricState(0,true); // clear list before reusing it! myCollisionList.clear(); // store all collisions of mySphere with descendents of rootNode, store in myCollisionList mySphere.findCollisions( rootNode, myCollisionList ); // determine how many there are numCollisions = myCollisionList.getNumber(); if (numCollisions > 0) { // when there are collisions, handle them in a loop. for ( int i = 0; i < numCollisions; i++ ) { myCollision = myCollisionList.getCollisionData(i); targetHit = myCollision.getTargetMesh(); //If the sphere intersects with our floorbox named "wally", we want it to stop if (targetHit.getName().equals("wally")) { //Therefore, when it tries to move inside of wally (causing the collision), put its translation back to where it was before it moved. mySphere.setLocalTranslation( oldPosition ); mySphere.setLocalRotation( oldRotation ); mySphere.updateGeometricState(0,true); } } } } public void processCollisions() { // COLLISION DETECTION - SPECIAL OBJECTS // check if two particular bounding volumes intersect. if ( mySphere.getWorldBound().intersects( leftSphere.getWorldBound() ) ) mySphere.setSolidColor( ColorRGBA.orange ); else if ( mySphere.getWorldBound().intersects( rightSphere.getWorldBound() ) ) mySphere.setSolidColor( ColorRGBA.green ); else mySphere.setSolidColor( ColorRGBA.yellow ); if ( leftSphere.getWorldBound().intersects( mySphere.getWorldBound() ) ) leftSphere.setRandomColors(); else leftSphere.setSolidColor( ColorRGBA.red ); if ( rightSphere.getWorldBound().intersects( mySphere.getWorldBound() ) ) rightSphere.setRandomColors(); else rightSphere.setSolidColor( ColorRGBA.blue ); } }