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Moving the point (vector) at an angle of + Libgdx

I want to move a point (Vector2) by an angle. I have my corner. but I'm not very good at math or libgdx. to get the angle i use this:

degrees = (float) ((Math.atan2(touchPoint.x - x, -(touchPoint.y - y)) * 180.0d / Math.PI) + 240.0f);

Now, I want to move the vector. but I really do not know what I should do ... I looked at the question, but it was something like a change in the angle, not the transmission. I think libgdx should have a function for this. please, help.

UPDATE:

 public class Games implements ApplicationListener { SpriteBatch spriteBatch; Texture texture; float x = 160; float y = 5; Vector2 touch; Vector2 movement; Vector2 position; Vector2 dir; Vector2 velocity; float speed; float deltaTime; @Override public void create() { spriteBatch = new SpriteBatch(); texture = new Texture(Gdx.files.internal("images/1.png")); touch = new Vector2(); movement = new Vector2(); position = new Vector2(); dir = new Vector2(); velocity = new Vector2(); speed = 5; deltaTime = Gdx.graphics.getDeltaTime(); } public void render() { Gdx.gl.glClear(Gdx.gl10.GL_COLOR_BUFFER_BIT); deltaTime += 0.5f; spriteBatch.begin(); begin(deltaTime); spriteBatch.draw(texture, position.x, position.y); spriteBatch.end(); } private void begin(float deltaTime) { touch.set(Gdx.input.getX(), Gdx.input.getY()); position.set(x, y); dir.set(touch).sub(position).nor(); velocity.set(dir).scl(speed); movement.set(velocity).scl(deltaTime); position.add(movement); } ; public class Games implements ApplicationListener { SpriteBatch spriteBatch; Texture texture; float x = 160; float y = 5; Vector2 touch; Vector2 movement; Vector2 position; Vector2 dir; Vector2 velocity; float speed; float deltaTime; @Override public void create() { spriteBatch = new SpriteBatch(); texture = new Texture(Gdx.files.internal("images/1.png")); touch = new Vector2(); movement = new Vector2(); position = new Vector2(); dir = new Vector2(); velocity = new Vector2(); speed = 5; deltaTime = Gdx.graphics.getDeltaTime(); } public void render() { Gdx.gl.glClear(Gdx.gl10.GL_COLOR_BUFFER_BIT); deltaTime += 0.5f; spriteBatch.begin(); begin(deltaTime); spriteBatch.draw(texture, position.x, position.y); spriteBatch.end(); } private void begin(float deltaTime) { touch.set(Gdx.input.getX(), Gdx.input.getY()); position.set(x, y); dir.set(touch).sub(position).nor(); velocity.set(dir).scl(speed); movement.set(velocity).scl(deltaTime); position.add(movement); } )); public class Games implements ApplicationListener { SpriteBatch spriteBatch; Texture texture; float x = 160; float y = 5; Vector2 touch; Vector2 movement; Vector2 position; Vector2 dir; Vector2 velocity; float speed; float deltaTime; @Override public void create() { spriteBatch = new SpriteBatch(); texture = new Texture(Gdx.files.internal("images/1.png")); touch = new Vector2(); movement = new Vector2(); position = new Vector2(); dir = new Vector2(); velocity = new Vector2(); speed = 5; deltaTime = Gdx.graphics.getDeltaTime(); } public void render() { Gdx.gl.glClear(Gdx.gl10.GL_COLOR_BUFFER_BIT); deltaTime += 0.5f; spriteBatch.begin(); begin(deltaTime); spriteBatch.draw(texture, position.x, position.y); spriteBatch.end(); } private void begin(float deltaTime) { touch.set(Gdx.input.getX(), Gdx.input.getY()); position.set(x, y); dir.set(touch).sub(position).nor(); velocity.set(dir).scl(speed); movement.set(velocity).scl(deltaTime); position.add(movement); } .nor (); public class Games implements ApplicationListener { SpriteBatch spriteBatch; Texture texture; float x = 160; float y = 5; Vector2 touch; Vector2 movement; Vector2 position; Vector2 dir; Vector2 velocity; float speed; float deltaTime; @Override public void create() { spriteBatch = new SpriteBatch(); texture = new Texture(Gdx.files.internal("images/1.png")); touch = new Vector2(); movement = new Vector2(); position = new Vector2(); dir = new Vector2(); velocity = new Vector2(); speed = 5; deltaTime = Gdx.graphics.getDeltaTime(); } public void render() { Gdx.gl.glClear(Gdx.gl10.GL_COLOR_BUFFER_BIT); deltaTime += 0.5f; spriteBatch.begin(); begin(deltaTime); spriteBatch.draw(texture, position.x, position.y); spriteBatch.end(); } private void begin(float deltaTime) { touch.set(Gdx.input.getX(), Gdx.input.getY()); position.set(x, y); dir.set(touch).sub(position).nor(); velocity.set(dir).scl(speed); movement.set(velocity).scl(deltaTime); position.add(movement); } ; public class Games implements ApplicationListener { SpriteBatch spriteBatch; Texture texture; float x = 160; float y = 5; Vector2 touch; Vector2 movement; Vector2 position; Vector2 dir; Vector2 velocity; float speed; float deltaTime; @Override public void create() { spriteBatch = new SpriteBatch(); texture = new Texture(Gdx.files.internal("images/1.png")); touch = new Vector2(); movement = new Vector2(); position = new Vector2(); dir = new Vector2(); velocity = new Vector2(); speed = 5; deltaTime = Gdx.graphics.getDeltaTime(); } public void render() { Gdx.gl.glClear(Gdx.gl10.GL_COLOR_BUFFER_BIT); deltaTime += 0.5f; spriteBatch.begin(); begin(deltaTime); spriteBatch.draw(texture, position.x, position.y); spriteBatch.end(); } private void begin(float deltaTime) { touch.set(Gdx.input.getX(), Gdx.input.getY()); position.set(x, y); dir.set(touch).sub(position).nor(); velocity.set(dir).scl(speed); movement.set(velocity).scl(deltaTime); position.add(movement); }
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2 answers

If I understand your question correctly, are you looking for a direction vector?

If this is the correct understanding, you can do something like this:

 // Declared as fields, so they will be reused Vector2 position = new Vector2(); Vector2 velocity = new Vector2(); Vector2 movement = new Vector2(); Vector2 touch = new Vector2(); Vector2 dir = new Vector2(); // On touch events, set the touch vector, then do this to get the direction vector dir.set(touch).sub(position).nor(); vector, then do this to get the direction vector // Declared as fields, so they will be reused Vector2 position = new Vector2(); Vector2 velocity = new Vector2(); Vector2 movement = new Vector2(); Vector2 touch = new Vector2(); Vector2 dir = new Vector2(); // On touch events, set the touch vector, then do this to get the direction vector dir.set(touch).sub(position).nor();

This will give you a normalized direction vector from position to touch point.

Then you can scale it up to speed, you want to move, and then use to update its position.

 velocity = new Vector2(dir).scl(speed);

And on each frame do something like this

 movement.set(velocity).scl(deltaTime); position.add(movement); ; movement.set(velocity).scl(deltaTime); position.add(movement);

Update

Here's what it would look like in a full class:

 class Game extends ApplicationAdapter { Vector2 position = new Vector2(); Vector2 velocity = new Vector2(); Vector2 movement = new Vector2(); Vector2 touch = new Vector2(); Vector2 dir = new Vector2(); Vector3 temp = new Vector3(); float speed = 100; OrthographicCamera camera; SpriteBatch batch; Texture texture; Sprite sprite; @Override public void create () { camera = new OrthographicCamera(); camera.setToOrtho(false); batch = new SpriteBatch(); texture = new Texture(Gdx.files.internal("data/badlogicsmall.jpg")); sprite = new Sprite(texture); Gdx.input.setInputProcessor(new InputAdapter() { @Override public boolean touchDown (int screenX, int screenY, int pointer, int button) { camera.unproject(temp.set(screenX, screenY, 0)); touch.set(temp.x, temp.y); return true; } }); } @Override public void render () { Gdx.gl10.glClear(GL10.GL_COLOR_BUFFER_BIT); update(Gdx.graphics.getDeltaTime()); batch.begin(); sprite.draw(batch); batch.end(); } @Override public void dispose() { texture.dispose(); batch.dispose(); } public void update (float deltaTime) { position.set(sprite.getX(), sprite.getY()); dir.set(touch).sub(position).nor(); velocity.set(dir).scl(speed); movement.set(velocity).scl(deltaTime); if (position.dst2(touch) > movement.len2()) { position.add(movement); } else { position.set(touch); } sprite.setX(position.x); sprite.setY(position.y); } } )); class Game extends ApplicationAdapter { Vector2 position = new Vector2(); Vector2 velocity = new Vector2(); Vector2 movement = new Vector2(); Vector2 touch = new Vector2(); Vector2 dir = new Vector2(); Vector3 temp = new Vector3(); float speed = 100; OrthographicCamera camera; SpriteBatch batch; Texture texture; Sprite sprite; @Override public void create () { camera = new OrthographicCamera(); camera.setToOrtho(false); batch = new SpriteBatch(); texture = new Texture(Gdx.files.internal("data/badlogicsmall.jpg")); sprite = new Sprite(texture); Gdx.input.setInputProcessor(new InputAdapter() { @Override public boolean touchDown (int screenX, int screenY, int pointer, int button) { camera.unproject(temp.set(screenX, screenY, 0)); touch.set(temp.x, temp.y); return true; } }); } @Override public void render () { Gdx.gl10.glClear(GL10.GL_COLOR_BUFFER_BIT); update(Gdx.graphics.getDeltaTime()); batch.begin(); sprite.draw(batch); batch.end(); } @Override public void dispose() { texture.dispose(); batch.dispose(); } public void update (float deltaTime) { position.set(sprite.getX(), sprite.getY()); dir.set(touch).sub(position).nor(); velocity.set(dir).scl(speed); movement.set(velocity).scl(deltaTime); if (position.dst2(touch) > movement.len2()) { position.add(movement); } else { position.set(touch); } sprite.setX(position.x); sprite.setY(position.y); } } ; class Game extends ApplicationAdapter { Vector2 position = new Vector2(); Vector2 velocity = new Vector2(); Vector2 movement = new Vector2(); Vector2 touch = new Vector2(); Vector2 dir = new Vector2(); Vector3 temp = new Vector3(); float speed = 100; OrthographicCamera camera; SpriteBatch batch; Texture texture; Sprite sprite; @Override public void create () { camera = new OrthographicCamera(); camera.setToOrtho(false); batch = new SpriteBatch(); texture = new Texture(Gdx.files.internal("data/badlogicsmall.jpg")); sprite = new Sprite(texture); Gdx.input.setInputProcessor(new InputAdapter() { @Override public boolean touchDown (int screenX, int screenY, int pointer, int button) { camera.unproject(temp.set(screenX, screenY, 0)); touch.set(temp.x, temp.y); return true; } }); } @Override public void render () { Gdx.gl10.glClear(GL10.GL_COLOR_BUFFER_BIT); update(Gdx.graphics.getDeltaTime()); batch.begin(); sprite.draw(batch); batch.end(); } @Override public void dispose() { texture.dispose(); batch.dispose(); } public void update (float deltaTime) { position.set(sprite.getX(), sprite.getY()); dir.set(touch).sub(position).nor(); velocity.set(dir).scl(speed); movement.set(velocity).scl(deltaTime); if (position.dst2(touch) > movement.len2()) { position.add(movement); } else { position.set(touch); } sprite.setX(position.x); sprite.setY(position.y); } } ()) { class Game extends ApplicationAdapter { Vector2 position = new Vector2(); Vector2 velocity = new Vector2(); Vector2 movement = new Vector2(); Vector2 touch = new Vector2(); Vector2 dir = new Vector2(); Vector3 temp = new Vector3(); float speed = 100; OrthographicCamera camera; SpriteBatch batch; Texture texture; Sprite sprite; @Override public void create () { camera = new OrthographicCamera(); camera.setToOrtho(false); batch = new SpriteBatch(); texture = new Texture(Gdx.files.internal("data/badlogicsmall.jpg")); sprite = new Sprite(texture); Gdx.input.setInputProcessor(new InputAdapter() { @Override public boolean touchDown (int screenX, int screenY, int pointer, int button) { camera.unproject(temp.set(screenX, screenY, 0)); touch.set(temp.x, temp.y); return true; } }); } @Override public void render () { Gdx.gl10.glClear(GL10.GL_COLOR_BUFFER_BIT); update(Gdx.graphics.getDeltaTime()); batch.begin(); sprite.draw(batch); batch.end(); } @Override public void dispose() { texture.dispose(); batch.dispose(); } public void update (float deltaTime) { position.set(sprite.getX(), sprite.getY()); dir.set(touch).sub(position).nor(); velocity.set(dir).scl(speed); movement.set(velocity).scl(deltaTime); if (position.dst2(touch) > movement.len2()) { position.add(movement); } else { position.set(touch); } sprite.setX(position.x); sprite.setY(position.y); } }

Notice that you could end the position of Vector2 and just use x and y directly, but I like to use Vector2 because it is a little cleaner.

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 float dy = touchPoint.y - y; float dx = touchPoint.x - x; degree = Math.atan2(dy, dx) * MathUtils.radToDegree;
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Source: https://habr.com/ru/post/1491803/

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