I'm reading a book about game development: Beginning Java Game Development with LibGDX.
There was a class named CheesePlease3 that I copied from the book, it presented the Stage class, and Actor class, I had to make a subclass from the Actor class, named BaseActor.
I did everything correctly, basically copy-pasted the whole thing, and it doesn't draw any object.
So my question is why? What is wrong?
Maybe the code itself a little bit long but easy to read.
Here is the CheesePlease3 class:
public class CheesePlease3 extends Game {
public Stage mainStage;
private BaseActor mouse;
private BaseActor cheese;
private BaseActor floor;
private BaseActor winText;
#Override
public void create () {
mainStage = new Stage();
floor = new BaseActor();
floor.setTexture(new Texture("floor.png"));
floor.setPosition(0, 0);
mainStage.addActor(floor);
cheese = new BaseActor();
cheese.setTexture(new Texture("cheese.png"));
cheese.setPosition(300, 300);
mainStage.addActor(cheese);
mouse = new BaseActor();
mouse.setTexture(new Texture("mouse.png"));
mouse.setPosition(200, 200);
mainStage.addActor(mouse);
winText = new BaseActor();
winText.setTexture(new Texture("youWon.png"));
winText.setPosition(150, 150);
winText.setVisible(false);
mainStage.addActor(winText);
}
#Override
public void render(){
// process input
mouse.velocityX = 0;
mouse.velocityY = 0;
if (Gdx.input.isKeyPressed(Input.Keys.LEFT))
mouse.velocityX -= 100;
if (Gdx.input.isKeyPressed(Input.Keys.RIGHT))
mouse.velocityX += 100;
if (Gdx.input.isKeyPressed(Input.Keys.UP))
mouse.velocityY -= 100;
if (Gdx.input.isKeyPressed(Input.Keys.DOWN))
mouse.velocityY += 100;
// update
float dt = Gdx.graphics.getDeltaTime();
mainStage.act(dt);
// check win condition: Mouse must be overlapping cheese
Rectangle mouseRectangle = mouse.getBoundingRectangle();
Rectangle cheeseRectangle = cheese.getBoundingRectangle();
if (mouseRectangle.contains(cheeseRectangle))
winText.setVisible(true);
// draw graphics
Gdx.gl.glClearColor(0.8f, 0.8f, 1, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
mainStage.draw();
}
And here is the BaseActor class:
public class BaseActor extends Actor {
public TextureRegion region;
public Rectangle boundary;
public float velocityX;
public float velocityY;
public BaseActor(){
super();
region = new TextureRegion();
boundary = new Rectangle();
velocityX = 0;
velocityY = 0;
}
public void setTexture (Texture t){
int w = t.getWidth();
int h = t.getHeight();
setWidth(w);
setHeight(h);
region.setRegion(t);
}
public Rectangle getBoundingRectangle(){
return boundary.set(getX(), getY(), getWidth(), getHeight());
}
#Override
public void act (float dt){
super.act(dt);
moveBy(velocityX * dt, velocityY * dt);
}
public void drawBatch (Batch batch, float parentAlpha){
Color c = getColor();
batch.setColor(c.r, c.g, c.b, c.a);
if (isVisible())
batch.draw(region, getX(), getY(), getOriginX(), getOriginY(),
getWidth(), getHeight(), getScaleX(), getScaleY(), getRotation());
}
And here is the DesktopLauncher:
public static void main (String[] arg) {
LwjglApplicationConfiguration config = new LwjglApplicationConfiguration();
new LwjglApplication(new CheesePlease3(), config);
config.title = "Mouse - Cheese";
}
The BaseActor has to override the draw method.
I assume the drawBatch method should be renamed to draw.
Ps.:
The movement for up and down is inverted.
In my game, I have my objects represented as a actors, thus all of the game objects would be on a Stage. For some reason when I try to move the Stage's camera around, it won't work, or actually it doesn't seem to work. I have added a game Actor to the location of 0,0. When I translate the camera's position around, the Actor still stays at the bottom left corner, despite when I log the camera's position, it shows that the camera has moved.
public class Striker extends Actor {
private Sprite img;
private World worldRef;
private Body body;
//constructor
public Striker(float size, float x, float y, World world) {
img = new Sprite(new Texture(Gdx.files.internal("Striker.png")));
//mains the aspect size ratio
img.setSize((275f / 300f) * size, size);
img.setPosition(x, y);
worldRef = world;
//set up the physics
BodyDef bodyDef = new BodyDef();
bodyDef.type = BodyDef.BodyType.DynamicBody;
bodyDef.position.set(x,y);
body = world.createBody(bodyDef);
}
#Override
public void draw(Batch batch, float parentAlpha) {
img.draw(batch);
}
#Override
public void act(float delta) {
super.act(delta);
}
#Override
public float getX() {
return body.getPosition().x;
}
#Override
public float getY() {
return body.getPosition().y;
}
#Override
public float getWidth() {
return img.getWidth();
}
#Override
public float getHeight() {
return img.getHeight();
}
}
The results of the 2 logs show that the camera's positions have moved, but it doesn't look like it.
public class StrikerScreen implements Screen {
public static float WIDTH = 1920;
public static float HEIGHT = 1080;
public static float PPM = 200;
private Launcher launcherRef;
private OrthographicCamera camera;
private FitViewport viewport;
private World world;
private Box2DDebugRenderer debugRenderer;
private Striker striker;
private Stage gameStage;
//constructor
public StrikerScreen(Launcher launcher) {
launcherRef = launcher;
world = new World(new Vector2(0, -9.8f), true);
debugRenderer = new Box2DDebugRenderer();
gameStage = new Stage();
camera = (OrthographicCamera) gameStage.getCamera();
viewport = new FitViewport(WIDTH / PPM, HEIGHT / PPM, gameStage.getCamera());
viewport.apply();
gameStage.setViewport(viewport);
striker = new Striker(160f / PPM, 0, 0, world);
gameStage.addActor(striker);
gameStage.getCamera().translate(viewport.getWorldWidth() / 2f, 500f, 0);
viewport.apply();
camera.update();
Gdx.app.log("StrikerScreen.java", "Camera position: " + gameStage.getCamera().position.toString());
Gdx.app.log("StrikerScreen.java", "Camera size: " + gameStage.getCamera().viewportWidth + ", " + gameStage.getCamera().viewportHeight);
}
#Override
public void show() {
}
public void update(float delta) {
world.step(1 / 30f, 6, 2);
gameStage.act(delta);
}
#Override
public void render(float delta) {
update(delta);
debugRenderer.render(world, camera.combined);
gameStage.draw();
}
#Override
public void resize(int width, int height) {
viewport.update(width, height, true);
}
#Override
public void pause() {
}
#Override
public void resume() {
}
#Override
public void hide() {
}
#Override
public void dispose() {
}
}
In the code you posted, the only times you move the camera are in the StrikerScreen constructor where you explicitly translate it, and in the resize method, where you have called viewport.update(width, height, true); Passing true to viewport.update tells it to move the camera to where (0, 0) is in the bottom left of corner of the viewport. Since resize is automatically called when you set your screen to this screen, that is the most recent position you have set the camera to.
I am developing an Android game using the libgdx box2d library in Eclipse. In the game, there's a ball that falls after touching the start button. But I get a nullpointerexception when the ball contacts the dynamic body.
On contact I want to applyLinearForce to that dynamic body. But I keep getting nullpointerexception on contact of the ball and dynamic body.
ContactHandler class:
public class ContactHandler implements ContactListener {
InputHandler input;
#Override
public void beginContact(Contact contact) {
if(contact.getFixtureA().getBody().getUserData() == "do1" && contact.getFixtureB().getBody().getUserData() == "ball"){
System.out.println("beginContact");
input = new InputHandler();
input.getBody1().applyLinearImpulse(10, 0, 0, 0, true);
}
}
InputHandler class:
public class InputHandler implements InputProcessor {
private OrthographicCamera camera;
private Ball ball;
private DragObject dragObject;
private boolean start = false;
private Vector3 touch = new Vector3();
private Vector3 dragTo = new Vector3();
public InputHandler(){
}
public InputHandler(OrthographicCamera camera, Ball ball,
DragObject dragObject) {
this.camera = camera;
this.ball = ball;
this.dragObject = dragObject;
}
#Override
public boolean touchDragged(int screenX, int screenY, int pointer) {
if (!start) {
for (Body body : dragObject.getBody()) {
if (touch.x > body.getPosition().x - dragObject.getWidth() - 1
&& touch.x < body.getPosition().x
+ dragObject.getWidth() + 1) {
if (touch.y > body.getPosition().y - dragObject.getHeight()
- 1
&& touch.y < body.getPosition().y
+ dragObject.getHeight() + 1) {
dragTo.set(screenX, screenY, 0);
camera.unproject(dragTo);
body.setTransform(dragTo.x, dragTo.y, 0);
touch.set(screenX, screenY, 0);
camera.unproject(touch);
}
}
}
}
return false;
}
public Body getBody1(){
return dragObject.getBody().get(0);
}
DragObject class:
public static Array<Body> bodies = new Array<Body>();
public static int count = 0;
public DragObject(){
}
public DragObject(World world, float x, float y, float width, float height) {
this.world = world;
this.width = width;
this.height = height;
initialize();
body1 = world.createBody(bodyDef1);
body1.createFixture(fixtureDef);
body1.setUserData("do1");
bodies.add(body1);
}
public Array<Body> getBody() {
return bodies;
}
Your constructor for the input handler is wrong, these lines should be removed:
public InputHandler(){
}
Because when you call this constructor here:
public void beginContact(Contact contact) {
if(contact.getFixtureA().getBody().getUserData() == "do1" && contact.getFixtureB().getBody().getUserData() == "ball"){
System.out.println("beginContact");
//You are using the wrong contructor, therefore body1 or dragObject is never initialised
input = new InputHandler();
//The null pointer exception is here, no body1 has been initialised yet
input.getBody1().applyLinearImpulse(10, 0, 0, 0, true);
}
You need to make the contructor match and create a new DragObject within the InputHandler class and as a side note it isn't very efficient initialising the class every time the body collides I am sure you can think of a better way to organise it.
In short:
I create Polygon object with a help of this method:
public static float[][] getPolygonArrays(float cx, float cy, float R, int sides) {
float[] x = new float[sides];
float[] y = new float[sides];
double thetaInc = 2 * Math.PI / sides;
double theta = (sides % 2 == 0) ? thetaInc : -Math.PI / 2;
for (int j = 0; j < sides; j++) {
x[j] = (float) (cx + R * Math.cos(theta));
y[j] = (float) (cy + R * Math.sin(theta));
theta += thetaInc;
}
return new float[][]{x, y};
}
and merge it to one dimension array with:
public static float[] mergeCoordinates(float[][] vertices) throws Exception {
if (vertices.length != 2 || vertices[0].length != vertices[1].length) throw new Exception("No valid data");
ArrayList<Float> mergedArrayList = new ArrayList<Float>();
float[] mergedArray = new float[vertices[0].length * 2];
for(int i = 0; i < vertices[0].length; i++) {
mergedArrayList.add(vertices[0][i]);
mergedArrayList.add(vertices[1][i]);
}
int i = 0;
for (Float f : mergedArrayList) {
mergedArray[i++] = (f != null ? f : Float.NaN);
}
return mergedArray;
}
I use 0 as value for X and Y for all newly created Polygons (named in code as Platform). And result of method mergeCoordinates i pass to method setVertices of Polygon object.
After this step i do setPosition with x = Gdx.graphics.getWidth()/2 and y = Gdx.graphics.getHeight()/2. Polygons are positioned good, right on the game screen center.
Than i create a new one Polygon, which must use origin coordinates from first Polygon object, this new polygon i named Figure. To set origin coordinates i use method setOrigin of Polygon class, and use X and Y of Platform Polygon object.
When i run method rotate of Platform Polygon object i also rotate Figure Polygon object, and Figure must rotate around origin point, center of Platform. But it does not.
Figure do rotation around bottom right corner.
For example:
my screen size is 640 x 480. Center point will be 320 x 240. This is X and Y of Platform Polygon object, i checked it with getX and getY of Polygon. I create Figure at 0,0, do setPosition(320, 200) (this is preferred orbit distance for figure to platform). And Figure positioned also good.
I run setOrigin(320, 240) for Figure Polygon Object.
I run rotate for Figure object. And it somehow think that right bottom corner have coordinates x = 320 and y = 240 and do rotation around this point.
Any could help me to solve this problem?
More details on problem you can find below(details, images, gifs, schemes and also sources).
More detailed part starts here
i'm trying to understand how coordinate system in libgdx work, cause i have a problem with positioning objects in game world.
I created simple application, with one big Red Polygon object(Platform in code),
10 White Triangle Polygons(Sector in code) which are included into big polygon object and inherits it's behavior(such like rotate, moveTo and etc).
Than i added inside each Sector one Green Polyline(Direction in code) from first vertice of Sector Polygon to midle point of the opposite side to first point.
This is technical line and i will use it's vertices(coordinates of two points) to move small Red Polygon Object(Figure in code), from center to oposite side to center point of Sector.
When i click on Stage and click coordinates are inside Platform i rotate it to the left or to the right(depends on where click was made). On rotate all Sectors and technical lines are rotated correctly.
http://i.imgur.com/s5xaI8j.gif
(670Kb)
As you can see on gif, figures rotates around theire's center point. I found that Polygon class has method setOrigin(float x, float y) and in annotation to this method said next:
/** Sets the origin point to which all of the polygon's local vertices
are relative to. */
So i tried to use this method, set origin X of Figure as center X of Platform and origin Y as center Y of Platform, and tried to rotate Platform.
http://i.imgur.com/pXpTuQi.gif
(1.06Mb)
As you can see, Figure polygon think that his origin coordinates are at right bottom corner. And Figure do rotation around right bottom corner.
I changed origin to next values: x = 50 and y = 50, here is a result:
http://i.imgur.com/Iajb9sN.gif
(640Kb)
I cannot get why it behave like that. What should i change in my logic?
I have not much classes in my project. I removed all imports and getters/setter to reduce amount of lines.
If it is necessary i could provide entire project.
GameScreen code:
public class GameScreen extends DefaultScreen {
private final GameWorld world;
private final GameRenderer renderer;
public GameScreen() {
world = new GameWorld();
renderer = new GameRenderer(world);
}
#Override
public void render(float delta) {
world.update(delta);
renderer.render();
}
#Override
public void resize(int width, int height) {
world.resize(width, height);
}
}
GameWorld code:
public class GameWorld {
private ArrayList < Platform > platforms = new ArrayList < Platform > ();
private OrthographicCamera camera;
private Stage stage;
private Array < Figure > activeFigures;
private Pool < Figure > figuresPool;
private long lastFigureTime = TimeUtils.nanoTime();
public GameWorld() {
setCamera(new OrthographicCamera());
getCamera().setToOrtho(true, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
setStage(new Stage());
getStage().setViewport(new ScreenViewport(getCamera()));
initializePools();
createPlatforms();
getStage().addListener(new InputListener() {
public boolean touchDown(InputEvent event, float x, float y, int pointer, int button) {
float degrees = Config.PLATFORM_ROTATE_DEGREES;
if (x <= Gdx.graphics.getWidth() / 2) {
degrees *= -1;
}
int i = getPlatforms().size();
while (i-- > 0) {
Platform platform = getPlatforms().get(i);
if (!platform.isLocked() && platform.isRotatable() && platform.getShape().getPolygon().contains(x, y)) {
platform.addAction(Actions.rotateBy(degrees, 1, Interpolation.bounceOut));
break;
}
}
return true;
}
});
Gdx.input.setInputProcessor(getStage());
}
private void initializePools() {
setActiveFigures(new Array < Figure > ());
setFiguresPool(new Pool < Figure > () {#Override
protected Figure newObject() {
return new Figure();
}
});
}
private void createPlatforms() {
float max = Gdx.graphics.getHeight() / (Gdx.graphics.getWidth() / (Gdx.graphics.getWidth() / 2));
float x = Gdx.graphics.getWidth() / 2;
float y = Gdx.graphics.getHeight() / 2;
float sides = 10f;
Color color = Color.RED;
createPlatform(x, y, max * Config.THIRD_PLATFORM_RADIUS_MULTIPLIER, sides, color, true, false, false, null);
}
private Platform createPlatform(float x, float y, float radius, float sides, Color color, boolean rotatable, boolean locked, boolean isEmpty, Platform relatedTo) {
Platform platform = new Platform(0, 0, radius, sides, color, isEmpty, this);
platform.moveTo(x, y);
platform.setRotatable(rotatable);
platform.setLocked(locked);
getPlatforms().add(platform);
getStage().addActor(platform);
if (relatedTo != null) {
relatedTo.addRelation(platform);
}
return platform;
}
private Figure createFigure(float x, float y) {
Figure figure = getFiguresPool().obtain();
figure.init(this, 0, 0, 10f, 4f, Color.DARK_GRAY);
figure.moveTo(x, y);
getActiveFigures().add(figure);
getStage().addActor(figure);
return figure;
}
public void spawnFigure() {
if (getActiveFigures().size >= 10) return;
if (TimeUtils.nanoTime() - getLastFigureTime() <= 2000000000) return;
Platform platform = null;
for (Platform p: getPlatforms()) {
if (!p.isEmpty()) {
platform = p;
break;
}
}
if (platform == null) {
setLastFigureTime(TimeUtils.nanoTime());
return;
}
Sector sector = platform.getSectors().get(MathUtils.random(platform.getSectors().size() - 1));
float x = platform.getX();
float y = platform.getY();
Figure figure = createFigure(x, y);
figure.origin(x, y);
x = sector.getDirection().getTransformedVertices()[2];
y = sector.getDirection().getTransformedVertices()[3];
figure.addAction(Actions.moveTo(x, y, 1));
setLastFigureTime(TimeUtils.nanoTime());
}
public void update(float delta) {
updatePlatforms(delta);
updateFigures(delta);
spawnFigure();
}
private void updatePlatforms(float delta) {
for (Platform platform: getPlatforms()) {
platform.update(delta);
}
}
private void updateFigures(float delta) {
Figure figure;
int figures = getActiveFigures().size;
for (int i = figures; --i >= 0;) {
figure = getActiveFigures().get(i);
if (figure.isAlive() == false) {
getActiveFigures().removeIndex(i);
getFiguresPool().free(figure);
} else {
figure.update(delta);
}
}
}
public void resize(int width, int height) {
getCamera().setToOrtho(true, width, height);
getStage().getViewport().update(width, height, true);
for (Platform platform: getPlatforms()) {
platform.resize(true, width, height);
}
for (Figure figure: getActiveFigures()) {
figure.resize(true, width, height);
}
}
}
GameRenderer code:
public class GameRenderer {
private ShapeRenderer shapeRenderer;
private GameWorld world;
private SpriteBatch spriteBatch;
public GameRenderer(GameWorld world) {
setWorld(world);
setShapeRenderer(new ShapeRenderer());
getShapeRenderer().setProjectionMatrix(getWorld().getCamera().combined);
setSpriteBatch(new SpriteBatch());
getSpriteBatch().setProjectionMatrix(getWorld().getCamera().combined);
}
public void render() {
Gdx.gl.glClearColor(0f, 0.2f, 0.4f, 1f);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
getWorld().getCamera().update();
getSpriteBatch().setProjectionMatrix(getWorld().getCamera().combined);
getShapeRenderer().setProjectionMatrix(getWorld().getCamera().combined);
getWorld().getStage().act(Gdx.graphics.getDeltaTime());
getWorld().getStage().draw();
renderGameObjects();
}
private void renderGameObjects() {
renderPlatforms();
renderFigures();
}
private void renderFigures() {
getShapeRenderer().begin(ShapeRenderer.ShapeType.Line);
for (Figure figure: getWorld().getActiveFigures()) {
figure.render(getSpriteBatch(), getShapeRenderer());
}
getShapeRenderer().end();
}
private void renderPlatforms() {
getShapeRenderer().begin(ShapeRenderer.ShapeType.Line);
for (Platform platform: world.getPlatforms()) {
platform.render(getSpriteBatch(), getShapeRenderer());
}
getShapeRenderer().end();
}
}
Platform code:
public class Platform extends GameObject {
private ArrayList < Sector > sectors = new ArrayList < Sector > ();
private ArrayList < Platform > relations = new ArrayList < Platform > ();
private boolean rotatable = true;
private boolean locked = false;
private void initialize(float cx, float cy, float radius, float sides, Color color) {
setPosition(cx, cy);
setRadius(radius);
setShape(ShapeType.POLYGON.getInstance(new float[] {
cx, cy, radius, sides
}, color));
}
public Platform(float cx, float cy, float radius, float sides, Color color, boolean isEmpty, GameWorld gameWorld) {
setGameWorld(gameWorld);
initialize(cx, cy, radius, sides, color);
setEmpty(isEmpty);
if (!isEmpty()) {
generateSectors();
}
}
private void generateSectors() {
float[] vertices = getShape().getVertices();
for (int i = 0; i < vertices.length; i += 2) {
try {
Color color = Color.WHITE;
if (i + 3 > vertices.length) {
getSectors().add(new Sector(new float[] {
getX(), getY(), vertices[i], vertices[i + 1], vertices[0], vertices[1]
}, color, this, i / 2));
} else {
getSectors().add(new Sector(new float[] {
getX(), getY(), vertices[i], vertices[i + 1], vertices[i + 2], vertices[i + 3]
}, color, this, i / 2));
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
public void rotateBy(float degrees) {
setRotation(degrees);
getShape().rotate(degrees);
for (Sector sector: getSectors()) {
sector.rotate(degrees);
}
for (Platform platform: getRelations()) {
platform.rotateBy(degrees);
}
for (Figure figure: getGameWorld().getActiveFigures()) {
figure.rotate(degrees);
}
}
#Override
public void moveTo(float x, float y) {
super.moveTo(x, y);
getShape().moveTo(x, y);
for (Sector sector: getSectors()) {
sector.moveTo(x, y);
}
for (Platform platform: getRelations()) {
platform.moveTo(x, y);
}
}
public void addRelation(Platform platform) {
if (platform.equals(this)) return;
getRelations().add(platform);
}
#Override
public void update(float delta) {
for (Sector sector: getSectors()) {
sector.update(delta);
}
}
#Override
public void dispose() {
for (Sector sector: getSectors()) {
sector.dispose();
}
}
#Override
public void render(SpriteBatch spriteBatch, ShapeRenderer shapeRenderer) {
render(spriteBatch);
if (Config.DEBUG_LAYOUTS) render(shapeRenderer);
for (Sector sector: getSectors()) {
sector.render(spriteBatch, shapeRenderer);
}
}
private void render(ShapeRenderer shapeRenderer) {
shapeRenderer.setColor(getShape().getColor());
shapeRenderer.polygon(getShape().getVertices());
}
public void resize(boolean reposition, int width, int height) {
if (reposition) {
moveTo(width / 2, height / 2);
}
}
}
Sector code:
public class Sector extends GameObject {
private Polyline direction;
private float[] vertices;
private Platform platform;
private int sectorId;
public Sector(float[] vertices, Color color, Platform platform, int sectorId) throws Exception {
setSectorId(sectorId);
setVertices(vertices);
initialize(vertices, color, platform);
}
private void createDirection() {
float[] vertices = getShape().getPolygon().getVertices();
float x1 = vertices[0];
float y1 = vertices[1];
float x2 = (vertices[2]+vertices[4])/2;
float y2 = (vertices[3]+vertices[5])/2;
setDirection(new Polyline(new float[]{ x1, y1, x2, y2 }));
}
public Sector(float[] vertices, Color color, boolean isEmpty) throws Exception {
initialize(vertices, color);
setEmpty(isEmpty);
}
private void initialize(float[] vertices, Color color) throws Exception {
if (vertices.length != 6) {
throw new Exception("Sector constructor expects 6 vertices");
}
setShape(ShapeType.TRIANGLE.getInstance(vertices, color));
createDirection();
}
private void initialize(float[] vertices, Color color, Platform platform) throws Exception {
if (vertices.length != 6) {
throw new IllegalArgumentException("Sector constructor expects 6 vertices");
}
setShape(ShapeType.TRIANGLE.getInstance(vertices, color));
setPlatform(platform);
createDirection();
}
public void rotate(float degrees) {
getShape().rotate(degrees);
getDirection().rotate(degrees);
}
#Override
public void moveTo(float x, float y) {
super.moveTo(x, y);
getShape().moveTo(x, y);
getDirection().setPosition(x, y);
}
#Override
public void render(SpriteBatch spriteBatch, ShapeRenderer shapeRenderer) {
render(spriteBatch);
if (Config.DEBUG_LAYOUTS) render(shapeRenderer);
}
private void render(ShapeRenderer shapeRenderer) {
shapeRenderer.setColor(getShape().getColor());
shapeRenderer.polygon(getShape().getVertices());
shapeRenderer.setColor(Color.GREEN);
shapeRenderer.line(getDirection().getTransformedVertices()[0], getDirection().getTransformedVertices()[1], getDirection().getTransformedVertices()[2], getDirection().getTransformedVertices()[3]);
}
}
Figure code:
public class Figure extends GameObject {
private GameWorld world;
public void init(GameWorld world, float cx, float cy, float radius, float sides, Color color) {
super.init();
setWorld(world);
initialize(cx, cy, radius, sides, color);
}
private void initialize(float cx, float cy, float radius, float sides, Color color) {
super.moveTo(cx, cy);
setRadius(radius);
setShape(ShapeType.POLYGON.getInstance(new float[] {
cx, cy, radius, sides
}, color));
}
#Override
public void moveTo(float x, float y) {
super.moveTo(x, y);
getShape().moveTo(x, y);
}
#Override
public void setPosition(float x, float y) {
if (!isAllowedToFlyFuther()) {
clearActions();
return;
}
moveTo(x, y);
}
private boolean isAllowedToFlyFuther() {
for (Figure figure: getWorld().getActiveFigures()) {
if (!figure.equals(this) && Intersector.overlapConvexPolygons(figure.getShape().getPolygon(), getShape().getPolygon())) {
return false;
}
}
return true;
}
#Override
public void reset() {
super.reset();
remove();
}
#Override
public void update(float delta) {}
private void render(SpriteBatch spriteBatch) {}
#Override
public void dispose() {}
#Override
public void render(SpriteBatch spriteBatch, ShapeRenderer shapeRenderer) {
render(spriteBatch);
if (Config.DEBUG_LAYOUTS) render(shapeRenderer);
}
private void render(ShapeRenderer shapeRenderer) {
shapeRenderer.setColor(getShape().getColor());
shapeRenderer.polygon(getShape().getVertices());
}
public void rotate(float degrees) {
setRotation(degrees);
getShape().rotate(degrees);
}
public void origin(float originX, float originY) {
setOrigin(originX, originY);
getShape().setOrigin(originX, originY);
}
public void resize(boolean reposition, int width, int height) {
if (reposition) {
//TODO: implement reposition for figures
}
}
}
GameObject code:
public abstract class GameObject extends Actor implements Poolable {
private int speed = 200;
private int baseSpeed = 200;
private boolean alive;
private float radius;
private GameWorld gameWorld;
private Shape shape;
private boolean empty = false;
public GameObject() {
setAlive(false);
}
public void init() {
setAlive(true);
}
public void reset() {
setAlive(false);
}
public abstract void update(float delta);
public abstract void render(SpriteBatch spriteBatch, ShapeRenderer shapeRenderer);
public abstract void dispose();
public void moveTo(float x, float y) {
super.setPosition(x, y);
}
}
Shape code:
public class Shape {
private Color color = new Color(Color.RED);
private float[] vertices;
private int sides;
private float radius;
private Polygon polygon = new Polygon();
public void rotate(float degrees) {
getPolygon().rotate(degrees);
setVertices(getPolygon().getTransformedVertices());
}
public void moveTo(float x, float y) {
getPolygon().setPosition(x, y);
setVertices(getPolygon().getTransformedVertices());
}
public void setOrigin(float originX, float originY) {
getPolygon().setOrigin(originX, originY);
setVertices(getPolygon().getTransformedVertices());
}
public void scale(float ratio) {
getPolygon().setScale(ratio, ratio);
setVertices(getPolygon().getTransformedVertices());
}
}
ShapeType code:
public enum ShapeType {
POLYGON {#Override
public Shape getInstance(float[] settings, Color color) {
try {
return new PolygonShape(settings, color);
} catch (Exception e) {
e.printStackTrace();
}
return new BaseShape();
}
},
TRIANGLE {#Override
public Shape getInstance(float[] settings, Color color) {
try {
return new TriangleShape(settings, color);
} catch (Exception e) {
e.printStackTrace();
}
return new BaseShape();
}
};
public abstract Shape getInstance(float[] settings, Color color);
}
PolygonShape code:
public class PolygonShape extends Shape {
public PolygonShape(float[] settings, Color color) throws Exception {
if (settings.length < 4) {
throw new IllegalArgumentException("Polygon shape constructor expects minimum 4 items in settings");
}
setSides((int) settings[3]);
setRadius(settings[2]);
setVertices(Utils.mergeCoordinates(Utils.getPolygonArrays(settings[0], settings[1], settings[2], (int) settings[3])));
getPolygon().setVertices(getVertices());
}
}
TriangleShape code:
public class TriangleShape extends Shape {
public TriangleShape(float[] settings, Color color) throws Exception {
if (settings.length < 6) {
throw new IllegalArgumentException("Triangle shape constructor expects minimum 6 items in settings");
}
setVertices(settings);
setColor(color);
getPolygon().setVertices(getVertices());
}
}
Utils code:
public class Utils {
public static float[] mergeCoordinates(float[][] vertices) throws Exception {
if (vertices.length != 2 || vertices[0].length != vertices[1].length) throw new Exception("No valid data");
ArrayList < Float > mergedArrayList = new ArrayList < Float > ();
float[] mergedArray = new float[vertices[0].length * 2];
for (int i = 0; i < vertices[0].length; i++) {
mergedArrayList.add(vertices[0][i]);
mergedArrayList.add(vertices[1][i]);
}
int i = 0;
for (Float f: mergedArrayList) {
mergedArray[i++] = (f != null ? f : Float.NaN);
}
return mergedArray;
}
public static float[][] getPolygonArrays(float cx, float cy, float R, int sides) {
float[] x = new float[sides];
float[] y = new float[sides];
double thetaInc = 2 * Math.PI / sides;
double theta = (sides % 2 == 0) ? thetaInc : -Math.PI / 2;
for (int j = 0; j < sides; j++) {
x[j] = (float)(cx + R * Math.cos(theta));
y[j] = (float)(cy + R * Math.sin(theta));
theta += thetaInc;
}
return new float[][] {
x, y
};
}
}
Config code:
public class Config {
public static final String LOG = TheGame.class.getSimpleName();
public static final boolean DEBUG_LAYOUTS = true;
public static final boolean SHOW_LOG = false;
public static final float PLATFORM_ROTATE_DEGREES = 36;
}
DesktopLauncher code:
public class DesktopLauncher {
public static void main(String[] arg) {
LwjglApplicationConfiguration config = new LwjglApplicationConfiguration();
config.title = "The Game!";
config.width = 1920 / 3;
config.height = 1080 / 3;
new LwjglApplication(new TheGame(), config);
}
}
Project structure:
Platform object structure and dependencies:
Render objects workflow
Im trying to add drag and drop functionality to several images in Libgdx. I have looked at this example: https://github.com/libgdx/libgdx/blob/master/tests/gdx-tests/src/com/badlogic/gdx/tests/DragAndDropTest.java but Its still not working. The images do not drag and drop. Would anyone be able to give me some pointers in why its not working?
Thanks
private void createButton() {
stage = new Stage();
Gdx.input.setInputProcessor(stage);
skin = new Skin();
skin.add("up", new Texture(Gdx.files.internal("assets/data/up.png")));
skin.add("def", new Texture(Gdx.files.internal("assets/data/Goal.png")));
final Image up = new Image(skin, "up");
up.setBounds(1090, 630, 40, 40);
stage.addActor(up);
Image def = new Image(skin, "def");
def.setBounds(1090, 585, 40, 40);
stage.addActor(def);
DragAndDrop dragAndDrop = new DragAndDrop();
dragAndDrop.addSource(new Source(up) {
public Payload dragStart (InputEvent event, float x, float y, int pointer) {
Payload payload = new Payload();
payload.setObject(payload);
payload.setDragActor(up);
payload.setDragActor(new Label("up", skin));
Label validLabel = new Label("up", skin);
validLabel.setColor(0, 1, 0, 1);
payload.setValidDragActor(validLabel);
return payload;
}
});
dragAndDrop.addTarget(new Target(def) {
public boolean drag (Source source, Payload payload, float x, float y, int pointer) {
getActor().setColor(Color.GREEN);
return true;
}
public void reset (Source source, Payload payload) {
getActor().setColor(Color.WHITE);
}
public void drop (Source source, Payload payload, float x, float y, int pointer) {
System.out.println("Accepted: " + payload.getObject() + " " + x + ", " + y);
}
});
render();
}
public void render () {
stage.act(Gdx.graphics.getDeltaTime());
stage.draw();
Table.drawDebug(stage);
}
I implemented your code on a project of mine.
I removed your render and used the one below. Also, you shouldn't need the assets/ prefix to your image import.
skin.add("up", new Texture(Gdx.files.internal("images/coin.png")));
skin.add("def", new Texture(Gdx.files.internal("images/coin.png")));
#Override
public void render(float delta) {
super.render(delta);
stage.draw();
stage.act(Gdx.graphics.getDeltaTime());
}
Another way to do drag in a better way...
public class CaveInterection implements ApplicationListener {
private OrthographicCamera camera;
private SpriteBatch batch;
private Texture bgTexture;
private Sprite sprite;
private Stage stage;
private Texture mirrTexture;
private MyActor mirrorActor;
Sprite img1,img2;
#Override
public void create() {
camera = new OrthographicCamera(1024, 550);
camera.position.set(1024 / 2, 550 / 2, 0);
batch = new SpriteBatch();
stage = new Stage(1024, 550, false);
//bgTexture = new Texture(Gdx.files.internal("data/cave.jpg"));
//bgTexture = new Texture(Gdx.files.internal("data/bg.jpg"));
mirrTexture = new Texture(Gdx.files.internal("data/mirror.png"));
mirrTexture
.setFilter(TextureFilter.Linear, TextureFilter.Linear);
mirrorActor = new MyActor(new TextureRegion(mirrTexture));
mirrorActor.setPosition(700, 400);
mirrorActor.setOrigin(mirrorActor.getWidth()/2, mirrorActor.getHeight()/2);
stage.addActor(mirrorActor);
// finally stage as the input process
Gdx.input.setInputProcessor(stage);
}
#Override
public void dispose() {
batch.dispose();
//bgTexture.dispose();
}
#Override
public void render() {
// clear the screen, update the camera and make the sprite batch
// use its matrices.
Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
camera.update();
batch.setProjectionMatrix(camera.combined);
batch.begin();
//batch.draw(bgTexture, 0,0);
// Gdx.app.log("arvind","X :"+mirrorActor.getX()+ " Y :"+mirrorActor.getY());
//batch.draw(bgTexture, 0, 0);
batch.end();
// tell the stage to act and draw itself
stage.act(Gdx.graphics.getDeltaTime());
stage.draw();
}
public class MyActor extends Actor {
TextureRegion region;
float lastX;
float lastY;
public MyActor (TextureRegion region) {
this.region = region;
setWidth(region.getRegionWidth());
setHeight(region.getRegionHeight());
addListener(new InputListener() {
public boolean touchDown (InputEvent event, float x, float y, int pointer, int button) {
Gdx.app.log("arv", "pointer1+"+pointer);
// we only care for the first finger to make things easier
if (pointer != 0) return false;
// record the coordinates the finger went down on. they
// are given relative to the actor's corner (0, 0)
Gdx.app.log("arvind", "touchDown");
Gdx.app.log("arv", "pointer2+"+pointer+""+x+"::::"+y);
lastX = x;
lastY = y;
return true;
}
public void touchDragged (InputEvent event, float x, float y, int pointer) {
// we only care for the first finger to make things easier
if (pointer != 0) return;
Gdx.app.log("arv", "touchDragged");
// adjust the actor's position by (current mouse position - last mouse position)
// in the actor's coordinate system.
translate(x - lastX, y - lastY);
// rotate(2);
// save the current mouse position as the basis for the next drag event.
// we adjust by the same delta so next time drag is called, lastX/lastY
// are in the actor's local coordinate system automatically.
lastX = x - (x - lastX);
lastY = y - (y - lastY);
}
});
}
#Override
public void draw (SpriteBatch batch, float parentAlpha) {
//batch.draw(region, getX(), getY());
batch.draw(region, getX(), getY(), mirrorActor.getOriginX(), mirrorActor.getOriginY(), mirrorActor.getWidth(), mirrorActor.getHeight(), 1, 1,getRotation(), true);
}
}
#Override
public void resize(int width, int height) {
}
#Override
public void pause() {
}
#Override
public void resume() {
}
}