Any good method to determine current player is standing on sth.?

[chengenzhao]

Hi:

Is there any built-in mechanism to determine whether player is standing on sth.?
Currently we keep the y-velocity of previous frame and decide whether character is standing on sth. by checking whether y-velocity of current frame and previous frame are ~0, if the answer is yes then the character is allowed to jump.
If no, then he won't jump
But I am not sure whether is the best practice or correct way to do it
so is there any built-in mechanism for us to check if the player is standing on sth.?

Thanks

[AlmasB]

Hi,

If the entity in question uses PhysicsComponent, then you can add a ground sensor:

FXGL/fxgl-samples/src/main/java/sandbox/PlatformerSample.java

Lines 201 to 205 in 8bda931

	private Entity createPlayer(double x, double y, double width, double height) {
	PhysicsComponent physics = new PhysicsComponent();
	physics.addGroundSensor(new HitBox(new Point2D(5, height - 5), BoundingShape.box(width - 10, 10)));
	physics.setBodyType(BodyType.DYNAMIC);

Then check:

FXGL/fxgl-samples/src/main/java/sandbox/PlatformerSample.java

Lines 122 to 124 in 8bda931

	player.getComponent(PhysicsComponent.class).onGroundProperty().addListener((o, oldValue, newValue) -> {
	System.out.println(newValue ? "On Ground" : "In the air");
	});

If the entity does not use PhysicsComponent, then what you are doing is probably a good approach.