Collision problem

[nightm4re94]

^{This post has been migrated automatically from the old LITIENGINE forum (2018 - 2022).
Posted: 2019-04-23 17:25:13
User: pma8444 [] (age: 1335 days 🔥; posts: 16)}
My top view tank consists of two entities, because the bottom and the tower should be controllable indepently
The tower is simply moved according the movement of the bottom:
this.tankMovementListener.tankMovement(this.getVelocityX(), this.getVelocityY());
The problem is, when the bottom is colliding with something, the tower does not notice:
https://giphy.com/gifs/gf5LboQR1RqR4mSwcZ
I cannot set the towers' @CollisionInfo collision=true, as tower and bottom then would collide with eachother.
Currently I'm also failing to figure out precisely whether the bottom is colliding and with what and how this affected it's movement.
TLDR; How can I pass the movement of the bottom to the tower, when the bottom is colliding with something?

[nightm4re94]

^{This post has been migrated automatically from the old LITIENGINE forum (2018 - 2022).
Posted: 2019-04-25 08:47:08
User: steffen [Admin 👑, Mod 🔧] (age: 1568 days 🔥; posts: 100)}
That's an interesting question. The first thing I want to mention here is the fact that the ~~~~Game.physics()..move(...) methods return a boolean value that indicates whether a collision had to be resolved or not.
This can be used to identify whether the bottom part collided with something. And you might write some code around this to remember the old location and compare it to the location after calling the ~~~~move method to get the actual delta of this operation. Then you could propagate this delta to your upper tank part.
The code could look somewhat like this:
~~```java~~Point2D old = entity.getLocation(); boolean success = Game.physics().move(this.getVelocityX(), this.getVelocityY()); if (!success) { Point2D newLocation = entity.getLocation(); double deltaX = newLocation.getX() - old.getX(); double deltaY = newLocation.getY() - old.getY(); this.tankMovementListener.tankMovement(deltaX, deltaY); } else { this.tankMovementListener.tankMovement(this.getVelocityX(), this.getVelocityY()); }```` Maybe, you could also always set the movement by the delta instead of the velocity, regardless of whether a collision occurred or not. Let me know if that helped. Sidenote: I can recommend setting ~~dbg_renderCollisionBoxes = true` in the ****~~config.properties**** when working on anything that is physics related.

[nightm4re94]

^{This post has been migrated automatically from the old LITIENGINE forum (2018 - 2022).
Posted: 2019-04-29 19:19:39
User: pma8444 [] (age: 1335 days 🔥; posts: 16)}
Your suggestion works, thanks. Really appreciate how quickly you guys answer questions 💯
Took me a while to figure out that you have to set the dbg_debugEnabled to true for the other debug-properties to work. :D
I expected Game.allowDebug(true) to do someting in this respect, but nothing seemed to have happened.