How to set the center of the actor to be the same as the center of mass of the body - libgdx

Question

Here is a star-shaped body created with Physics Body Editor with the center of mass in the middle:
val bodyEditorLoader by lazy { BodyEditorLoader(Gdx.files.internal("phisics/GameBox2D.json")) }
val starBody = createStar()
private fun createStar(): Body {
val bodyDef = BodyDef().apply {
type = BodyDef.BodyType.DynamicBody
position.set(
mainLayoutUtil.getSizeW(700f),
mainLayoutUtil.getSizeH(350f),
)
}
val body = WorldUtil.world.createBody(bodyDef)
val fixtureDef = FixtureDef().apply {
restitution = 0.7f
density = 1f
}
bodyEditorLoader.attachFixture(body, "Star", fixtureDef, 10f)
return body
"rigidBodies": [
{
"name": "Star",
"imagePath": "../star.png",
"origin": {
"x": 0.5,
"y": 0.5,
},
}
...
]
The image that needs to display the body data:
private val starImage = Image(SpriteManager.GameRegion.STAR.region)
Image rendering method according to body data:
override fun render(delta: Float) {
super.render(delta)
WorldUtil.update(delta)
WorldUtil.debug(viewport.camera.combined)
renderStar()
}
private fun renderStar() {
starImage.apply {
x = starBody.???
y = starBody.???
setOrigin(starBody.???)
rotation = Math.toDegrees(starBody.???).toFloat()
}
}
What body data should I use to correctly render the image according to the body data?

Answer 1

Create a variable into which the Vector2 will be written:
var starCenter = Vector2()
In the body creation method, write the center of mass to the already created variable:
private fun createStar(): Body {
val center = bodyEditorLoader.getOrigin("Star", 10F)
starCenter = center
return body
}
Replace the image data with the following body data to render the image correctly:
private fun renderStar() {
starImage.apply {
x = starBody.position.x - starCenter.x
y = starBody.position.y - starCenter.y
setOrigin(starCenter.x, starCenter.y)
rotation = Math.toDegrees(starBody.angle.toDouble()).toFloat()
}
}