Why does using PhotonRigidbody2DView give 'elastic' movement? - unity3d

I'm currently using photon pun 2 to learn simple 2d multiplayer.
Using PhotonRigidbody2DView is giving an 'elastic' movement to the player. The player goes forward a bit and then returns to the original position.
Here's the video:
https://youtu.be/HgFVsofVZcQ
Why does this happen and how do I solve this?
I tried using PhotonTransformView and PhotonTransformViewClassic but it is giving weird results. The players go inside each other and when one player collides the other, the other player starts jittering.
So I decided to use PhotonRigidbody2DView instead. Now the players don't go inside each other and the jittering is also not happening but the 'elastic' movement problem is happening.

This happens because the remote client uses the velocity of the rigidbody to reproduce the movement of the character is does not control. This makes it a bit independent from the lag but for arcade style movement (where direction changes are immediate), this doesn't work all that well.
Solutions to this depend on what you actually need. Networked objects combined with physics can be tricky to get right. For PUN 2, we didn't implement a solution to this case and assumed you'd tweak the PhotonRigidbody2DView as needed.
The Smooth Sync package in the Asset Store seems to do well and is a plugin to PUN 2.
Alternatively, the newer Photon SDK "Fusion" should do better and is state of the art as networking solution.

Related

Recommended strategy for overriding certain Rigidbody collisions in Unity?

I'm looking for a little newbie advice on gamedev strategy and/or approach. I'm working on a game that uses Rigidbody physics in Unity and I've got a character interacting nicely with physical objects in the game world. The thing I'm trying to work through is that there are certain physical interactions that I want to control, but my own attempts to control them are conflicting with what Unity is already (correctly) doing.
For simplicity, let's just say I've got a Rigidbody-based player, and when certain Rigidbody-based objects collide with that player, I want to override where they deflect to. When I detect the collision and apply my own force with rb.AddForce(myForceVector, ForceMode.VelocityChange), Unity is also applying it's own force as a result of the same collision. I also tried setting the velocity directly with rb.velocity = myForceVector, which mostly works, but there are still situations where Unity applies force after I set the velocity so it's glitchy at best.
Other options I've considered are:
Use an additional, larger IsTrigger collision mesh to detect and handler the special type of collision I'm looking for before the actual collision occurs. That might work for slower speed projectiles, but likely will have the same issue for faster collisions.
Change the player to not being Rigidbody-based, which might work, but would require me to code a lot of the other interactions that are already working out of the box with Rigidbody physics.
Use RayCasting to detect when these special collisions might occur next and handle them before the actual collision. This is where I'm leaning currently.
Anyone have a recommended best practice for this kind of thing?
Thanks in advance!
The easiest way might just be to take full control. On the correctly timed press, disable the RigidBody and the Collider. Then just move it yourself to the target location. It's really hard to get precise control over a RigidBody -- every FixedUpdate(), it might be picking up force from collisions, and there can be many FixedUpdate() calls between Update() calls.
You could write a pretty simple coroutine using a Lerp() or Slerp() between the object's current and target position. That way, you could fully control how the object moves toward its target.
Just to follow up... I attempted to "take full control" as suggested in Alex M's answer above, but that ended up making a number of other things complicated in my specific situation. However, his comments about disabling the collider in the original question led me down a different path that ended up working well...
I ended up disabling the collider for the deflecting rigidbody upon impact and setting the velocity of the deflected body directly. That way, I was able to avoiding any additional force(s) applied from Unity while the collision was active. Once the deflected object was on it's way, I just had to reenable the collider.
Thanks, Alex!

Collision issue when player moves from one object to another

In unity 5 I am having an issue with certain collisions. I made a basic maze-like game where the player controls a cube across platforms (made from other cubes). In certain areas, two or more of the platforms touch so the player can get to different areas of the level. The problem with my collision happens at these intersections. The player will seem to get stuck for no reason and they would have to back up and get a running start in order to get to the other platform. I went through everything and made sure they are lined up perfectly in the unity editor but nothing seems to fix this.
Any advice would be greatly appreciated .
EDIT: all of my objects are using box colliders
A common (and good) practice is to use a Circle collider on the bottom of your character object in conjunction with a Box collider.
For Example:
While this will likely fix your issue, the source of the problem is probably using many small tiled cubes each with their own colliders. A large amount of tiled objects with colliders most likely cause performance and collision issues.

How to ensure sprites face the correct direction at all times in a 2D top down game. (logic)

I am making a multiplayer top down 2D game with 3d elements. All my movement, healthbars and basic functionality is working flawlessly even while hosted and playing on a server, node.js socket.io. However In this game it is possible to move the camera like in Realm of the mad god.
in case you are in doubt here is a video: https://youtu.be/4tdcxl3aZ0c?t=31s
This of course means that the players can end up being upside down with regards to each other and I cannot find a solution that works in all regards to make sure the sprites of the other players are always facing the correct direction with regards to their movement.
I have made several solution to this problem which cover most scenarios but while play testing other things we always end up noticing that the sprites sometimes face the wrong directions. So I am wondering if anyone has an answer, the logic, the fixing this problem.
Things I have tried:
Adding a gameobject to the camera to which all sprites asses their change in distance and determine their facing direction based off that information. (this leads to the players sometimes flipping erratically when the camera is moved and they as well are moving as sometimes they may be moving slower and there although moving left the camera approaches from the right and that flips them)
Adding a gameobject to the world which allows all sprites to have a fixed point to which they can measure their change in distance and therefore also know what direction to face (this worked somewhat better as they always know what direction they have to face, however once the player is upside down everything is inverted)
Emitting to the other players wether I am upside down or not in order to try to reinvert the above solution in the case I am upside down. (I could not find a good way to do this, and it got me thinking that this must be a problem people have fixed before many times and perhaps someone know of a good solution that works.)
thank you all for your input.
I seem to have found a solution for this issue that works decently well. Keeping in mind that I do not want to have the server being involved in this and I would rather have each individual sprite know its direction rather that have something heavy trying to determine this logic I came up with the following solution. May not be the best but it works. Still very keen to hear other solutions.
On my main character I have a switch case, which changes depending on the players rotation in the world. I need this switch case anyway for fixing (http://answers.unity3d.com/questions/1348301/trying-to-change-the-cameratransparencysortaxis-to.html?childToView=1348316#answer-1348316) that issue.
As the cases change I simply place the gameobject that I want the sprites to compare their distance to at 1 of 4 positions. YPos, YNeg, XPos, XNeg. Meaning that the sprite now determines its facing direction based on a gameobject that is placed in accordance with the Players position. without having to place it on the camera.
I will update if during further play tests this gives me trouble but thus far it works in the all the cases I need it to.
Still very willing to hear other solutions to this problem.
Thank you.

Unity3D: Recalculating collisions after Physics2D.IgnoreLayerCollision()?

I have my "player" gameObject standing atop a platform. He press a combination of keys, I verify that he's standing on the right kind of platform, and I run this code:
Physics2D.IgnoreLayerCollision(playerLayer, plataformLayer);
The intention being that he'd drop down from the platform. Instead, nothing happen immediately. The player is still atop the platform and can move around - only if he gets out of it and tries to get back to it, only at that point will he fall down from it.
So I made a temporary ugly workaround:
Physics2D.IgnoreLayerCollision(playerLayer, plataformLayer);
rigidbody2D.AddForce(transform.up * jump / 1.5f);
This will force the player to jump, making Unity "recalculate" the collisions and the player will, as I want to, pass through the platform. The even weirder part is: if the jump isn't high enough (100 force at 1 mass with 0.5 gravity scale seems to be the minimum), the player will still land on the platform, even though Unity is supposed to be ignoring those collisions.
I also tried pushing the player downwards, both with force and direct velocity, but no luck - he still collides with the platform, he only stops colliding with it after being away from it once.
Also, my player Rigidbody2D Detection Mode is set to Continuous, and I tried setting the platform up in many different ways, with and without a Rigidbody2D.
Any ideas on how to make the player instantly fall down from the platform as soon as collisions start being ignored? Thanks in advance.
I had been having the exact same issue. I have an alternative solution that you may find to your liking.
Rather than disabling or moving the terrain to be ignored, temporarily set the rigidbody2D of your player gameObject to kinematic. This will not cause you to 'drop' through the platform as you would like - but it will allow you to create the illusion that you are, by briefly using transform.Translate (or Vector3.Lerp, if you like) to move your character down via code.
This will disable Rigidbody2D.AddForce, but will still allow for set movement via rigibdody2D.velocity, if that is preferable to manipulating the transform directly.
Ensure the downward velocity lasts only as long as you are Kinematic, and try to let it match the gravity of your game, and it looks pretty seamless.
If you turn the rigidbody back on too quickly, it can (even with ignoreLayers :/ ) still jump back up to the platform - but if you leave it on too long, you can drop through more than one intended one-way platform, or even :O through the bottom of the stage!
This is easily avoided if you can be careful - personally I used both MonoBehaviour.Invoke to set a very short time limit on how long the player would remain Kinematic (about 0.5 seconds), AND I disabled Kinematic as soon as they moved 0.5 units from the point where the 'hopDown' was initiated.
If your gravity / platforms / character scale are vastly different than my own, you may have to experiment with some different numbers.
This has been my first attempt at an answer on stackoverflow, so I hope it has been helpful!
One easy way to do this is after calling
Physics2D.IgnoreLayerCollision(playerLayer, plataformLayer);
You reset the player's layer:
player.gameObject.layer = playerLayer;
It's sounds like you have covered a ton of possible solutions to this problem before coming here so, good job there. I listed a few alternative ideas below. I hope they help. Good luck!
Remove the collision object from the platform itself.
Offset the collision object to be in some remote location so it will not interact with the player. Offsetting the object may cause the collision to have a similar reaction to the jump you mentioned.

Unity: Third Person Collision with Animated Platforms

first time posting on stack and everything looks promising so far! I had a bit of a complicated question here so I'll do my best to provide exact details of what I'd like to get accomplished. I'm working with a third person controller in unity, so far everything is going great. I've dabbled with basic up and down platforms, a little glitchy but things work. Anytime my player runs through a mesh I make sure the mesh collider is working and a 'rigid-body' is attached set to Kinematic. Here's the kicker, in my game I have turning gears which the player can jump on. This is great except for the player doesn't turn with my gear, which would make sense according to my game-play. What would be the process for getting my character to interact with this animated mesh? I imagine some sort of script which my nooby mind cannot fathom at this point in my unity career. If anyone out there knows the solution to this, I would love to have any assistance, either way I'll plugging away at a solution. Thanks again!!
This is assuming that you're using the packages that ship with Unity3D, which it sounds like you are. After importing the Character Controllers package, you'll have a bunch of scripts in the Standard Assets\Character Controllers\Sources\Scripts folder, in the project hierarchy view. There's a script in there called CharacterMotor.js, attach that to the same GameObject you're running ThirdPersonController on.
Essentially this script adds more interactivity between the character and the scene. There's several methods inside this script that automatically move the character when in contact with a moving object (as long as it has a collision mesh) basically by inheriting the object's velocity.
If your gear/cog wheel has a proper collision mesh set up, adding this script to your character should be all that you require.