James Koon
Comments
Why is this postponed? Shouldn't it be Reopened and assigned so it can be fixed sometime this year? This bug is very annoying and is persisting through the 1.10 snapshots.
@Eddie Bingham Also, beyond what Fabian mentioned, the behavior you indicated is not a bug. If you want to resolve your issue, make new portals at the correct coordinates. Portals attempt to place in the nether at x/8 y z/8, and from the nether to overworld x*8 y z*8, as long as that place is not obstructed.
311 66 137 (Over) to Nether is 38 66 17. If this area is obstructed by netherrack or lava, it attempts to place you close to land.
25 98 34 (Nether) to Overworld is 200 98 272, which is only a couple blocks off from your reported 198 72 274. (98 is adjusted to land level)
If you want your overworld portal to connect to the 38 66 17, go there, dig it out or place a platform, build a new portal and light it. It will link properly.
While I agree with the opening a new ticket, the invulnerability does not negate all damage... if you catch fire in the portal, you'll continue to take damage.
Confirmed for Pre-Release 4.
Video showing this bug:
https://youtu.be/ANfvuxkLV58
@Early Reflections @Matthew Barnes
Even if it is temporary, you're still able to catch fire, which can lead to death after the invulnerability ends.
Either way, I'm pretty sure that they tweaked something with the anti-cheat in 15w40-15w41 era, and that tweak is the culprit here. If they disabled the anti-cheat system, it would probably be a bad thing for release, as modded clients would allow for crazy speeds and teleporting for non-opped players.
It seems as if they added invulnerability on dimension change in Pre4. This is a work around, and IMO just lazy & sloppy programming due to the following reasons:
1 - It will still generate chunks in the nether far from the origin of the map. For example: Teleporting at 4000 70 4000 in the overworld would load 500 70 500 in the nether without this bug. However, this bug effectively generates chunks that may never be visited in the nether, at 4000 70 4000.
2 - It increases server load. Using the previous example, the fact that when you teleport from 4000 70 4000 in the over world to 500 70 500 in the nether, the chunks at 4000 70 4000 as well as 500 70 500 must load in the nether due to this bug. One person doing this at a time isn't a big issue, but if you have numerous people going through the nether on a multiplayer server, it has the potential to increase overall load on the server quite significantly. If this is also happening in the end, it's even worse.
3 - You can still catch fire while invulnerable. You then proceed to take damage afterwards.
Here is the video I took of Single Player opened to LAN on Pre-4 (my server isn't updated yet). It shows clearly that you are still teleported to the overworld equivalent coordinates, due to the setup I used this time.
EDIT: I did additional testing by running a server. Each time you go through the portal, the console states "darthkoonstyle moved too quickly!"... assuming now that if the Anti-Cheat system were set to ignore dimension shifts, this bug might disappear entirely.
Updated the bug report with Pre-3, error is still occurring.
Ultimately, I do believe this bug is in fact being caused by the anti-cheat system saying you moved to fast. Subsequent bug fixes since 15w42a have only been bug fixing the effects of this bug, not the cause.
youtu.be/2GG7bk-Hnqo?a
Would love to be able to test this with a console open but alas I cannot at this time without running a server off of my computer... is "Player moved too fast" errors still occurring during nether transports?
Not understanding how the dev's aren't understanding the issue here. Something about the anticheat movement measure is temporarily teleporting people back to their overworld coordinates when going to the nether, and vice-versa if going to the overworld. All of the other bug fixes have been fixing the effect, not the cause. Fixing this would have resolved the damage issue, looping issue and wrong coordinate issue, and probably any other issue with the portals in the game... Not trying to be mean here, but I don't understand how they're not getting the cause and why this wasn't fixed in 15w43+. Sorry, just getting frustrated here repeating myself over and over.
@akiva silver You would think, but considering they're planning on releasing tomorrow... there are quite a few other bugs that have yet to be resolved as well...
This video was originally made for MC-89928, but it offers a side by side shot of what's happening in Pre2, if you would like to add it to the description.
In Pre-release2:Can confirm, no mobs are spawning at any difficulty in any naturally generated spawner (tested Skeleton, Spider and Zombie on both a newly generated world as well as on a pre-existing server).
@redstonehelper: Hi, here is a new video proving the exact thing still happens in 1.9-pre2. The exact same procedure was implemented. If you want I can record in a fresh world, but I was having a problem with my camera account connecting for some odd reason on an Open to LAN session from the same computer.
@Stuart Actually, if you have another person observing the location of the portal in the opposite dimension, you sometimes will see that person appear. This has not changed.
Here is a video in Pre-1, but these results are reproducable in Pre-2. My server just happens to be on Pre-1, and it was easier to setup my camera account on the server, and it outlines the following:
-Taking damage while inside of a block or lava is NOT the bug. This is the EFFECT of the bug.
-This bug is the CAUSE of all of the damage bugs.
-I go on to show live what happens when a person teleports while this is happening.
Ultimately, this bug is the one that needs to be fixed.
@redstonehelper The single tick of damage is caused SOLELY by this bug. It's caused by the game teleporting you to the wrong coordinates (which would be this bug), which happen to be in solid blocks (or catches you on fire if it's lava). This is still going on in even Pre-2. Why are we opening new tickets for the results of a bug? If this bug was fixed all of the damage on teleport bugs would simply cease being a thing, and to be honest, I think it's leading the Devs down the wrong path.
@Fenhl this may be due to some type of fire resistance or invulnerability. It makes no sense that you take a tick of suffocation but not lava damage unless this was the case...
I've noticed that my admin noted that most of the "moving too fast" errors had disappeared from the console in the most recent Pre-Release versions, EXCEPT for when people were traveling through the portals... My question: is this, like suggested on other bugs close to this (MC-89928, MC-90605 and maybe others), could this be an issue with the server saying "you moved too fast from coordinate "x" to "x/8" (or conversely from x to x*8) and temporarily teleporting you back? I'm half wondering if half of these bugs that have been 'patched and closed' are actually useless code that have acted as bandaids for an over-active anti-cheat measure? Sorry if the logic in my mind is not making sense, but if all of these fixes since 15w42a have been fixing the end result of the bugs instead of what's causing them, won't the remaining cause still be the same and cause overall instability in the system, let alone server resources (loading unneeded chunks, network traffic, etc)?
I'll give a reason my mind says MC-90605 was happening that relates to this bug: You teleport to the dimension, anticheat tries to put you back, something added in 15w42+ puts you back in the portal, next thing you know you're being transferred back to the previous dimension because you entered and then left the portal then came back (all by the servers doing), and you get looped back because the cooldown on the nether portal looping is now broken by you entering and leaving then reentering (read above, but the servers doing). Now it was fixed in 16w06 by adding a cooldown. — AGAIN, this is fixing the result, not what caused the result.
My message to Mobius... look into, at least for a second, the root of the issues. Which I believe at this point the anti-cheat measure saying you moved too fast. Then you could probably remove all of the added bloat of correcting a bug that has cascaded into everything from changing dimensions to portal looping by breaking preexisting mechanics that were designed to prevent this in previous versions of the game.
After testing, I can confirm that people are no longer looping on my server as often. I have yet to see someone actually loop (it seems the portal cooldown has been increased). Also, the nether seems to be loading faster. However, I can also confirm that MC-89928 is still a problem as per my previous post. You can see people pop in at the appropriate overworld coordinates in the nether. I'll notate that on the other post.
Spider, in response, I'm wondering if server lag is also enhancing the looping issues. If there is a case where you are teleporting, and the command block is lagged with the game code, the game code would probably take precedence. The client may think you're away from the portal, but the server itself is probably rubberbanding back to the portal. Does this tend to happen when there is block lag on the server? Or has it happened after a server restart?
Happ, I slightly disagree with you saying these bugs are at their core separate problems. In reality it's cause and effect.
As I said in my previous comment, the reason that this bug was even a bug at all is because of MC-89928. The reason I say this is that when you get teleported into a portal frame when switching dimensions, the game does not let you teleport again until you've left the block space of a portal block animation, then move back in. Part 3 below is where this functionality is being broken by MC-89928. Follow my logic here:
1-If you go through a portal, you appear where you're supposed to appear (Overworld Coordinates /8).
2-The game (anti-cheat, probably) thinks you've moved too fast, and teleports you back to the coordinates you were at previously in the overworld. The key to this is that this action REMOVES you from the portal frame.
3-Probably due to another fix implemented in 15w42a, you are then teleported BACK to the portal. Now the game thinks that you left and reentered the portal.
4-If you have a slow connection or slow computer, due to loading and then reloading an area (or in case of first use, generating new chunks), you may not be able to move out of the portal in time. Thus you teleport back THROUGH the portal.
5-At this point rinse and repeat.
As mentioned before, step 3, where the game removes you from the portal and puts you back into it is what caused this bug (MC-90605), because if you were able to teleport the first time without the game moving your coordinates, you wouldn't be ABLE to go back through the portal to begin with. Any fixes they applied because of this bug is fixing the results of another bug, which is rather ineffective, because all of this work on this bug will be negated by fixing MC-89928.
Thus this bug in and of itself was the wrong thing to focus on, in hindsight. Though the extra code will ultimately be a nice safeguard in case of other issues in the future.
The only thing they could have done to fix this bug without fixing MC-89928 is to put a cooldown timer on being able to activate a portal. I'll post the results of testing my hypothesis and my actual 16w06a findings probably by the morning, tomorrow afternoon at latest.
Actually, I'd warrant to say that MC-89928 is what was causing MC-90605 (that is now "fixed")... The fact that the game was teleporting you into the portal, then it teleports you to the location you were in the overworld again, and then back, was causing load time issues, and it also 'broke' the functionality that you couldn't teleport after you teleported into a portal frame (because technically you left it and came back).
This can be seen if you are standing on the otherside of the portal when someone teleports in. Say you are teleporting from 800 x 70 x 800 in the overworld to the Nether. At the nether portal at x=100 z = 100, they appear, disappear then reappear. If you are observing at 800 x 70 x 800 in the nether at the same time, you'll see the player appear and then disappear. This is also why people sometimes take suffocation or fire damage... if there is a block or lava at 800 x 70 x 800 in the nether, they'll take whatever damage from what blocks are in that location.
Actually, I'd warrant to say that MC-89928 is what was causing MC-90605... The fact that the game was teleporting you into the portal, then it teleports you to the location you were in the overworld again, and then back, was causing load time issues, and it also 'broke' the functionality that you couldn't teleport after you teleported into a portal frame (because technically you left it and came back).
This can be seen if you are standing on the otherside of the portal when someone teleports in. Say you are teleporting from 800 x 70 x 800 in the overworld to the Nether. At the nether portal at x=100 z = 100, they appear, disappear then reappear. If you are observing at 800 x 70 x 800 in the nether at the same time, you'll see the player appear and then disappear. This is also why people sometimes take suffocation or fire damage... if there is a block or lava at 800 x 70 x 800 in the nether, they'll take whatever damage from what blocks are in that location.
Glad someone actually looked into this... hopefully someone at Mojang can fix this, I'm tired of policing nether portals on my server. 😃