Dock-clips and undocumented movement mechanics: some overanalysis of moving around in the Urbz
5 years ago
United States

#Intro and Context

Hi everyone, I'm Splarin. I greatly enjoyed Urbz: Sims in the City when I was a kid, and recently took interest in running the game.

While looking at BTBSteve's channel, current record holder, I noticed he had posted some glitches, including a clip into the river in his video below,

,

in which he discussed the glitch potential represented by clipping from the right side of on Nutria Island into the river.

This led me down a bit of a rabbit hole trying to explore the glitch's implications, which led to me discovering and interacting with a number of mechanics I don't think are documented anywhere else about the game's movement.

The long story short is that I didn't find too much that'd help the run, and most (all?) of the below isn't particularly groundbreaking, so I strongly encourage you to lower expectations. I found a possible micro-optimization or two for the run, and I've proposed a few "next steps" towards the bottom in the hopes that the impact on the run increases. I hope someone goes further than I did and maybe finds something neat.

Lastly, Keep in mind everything I've written was DS specific. It's possible the GBA version has things I missed (it came first and is supposed to be more buggy!), so take everything here with a grain of salt if you're on GBA, and you are encouraged to verify on your platform that you get matching behavior.

I originally started the search with one goal in mind: early fanboat.

The BTBSteve river glitch from Nutria island was cool, but like he said, in the context of a run it's not a huge deal: if you already have the fanboat to get to Nutria Island, a river-clip isn't useful to you, because you already finished the Bayou and have Glasstown access: Access to the river doesn't give you anything particularly new.

So, to just be in the river isn't particularly helpful because we can't get out anywhere...

...But what if we could?

I thought it might be possible that the fanboat already existed at the Glasstown dock, and the game just chooses to hide it from you in later chapters until you formally unlock it at the normal time. A bit of a longshot...

...But if we had access to the fanboat, we could access all docks. That could open up Paradise Island, Glasstown, the Bayou, and effectively open the entire game as early as the very start of mission 3, which I believed probably would unearth a swarm of followup glitches.

I had to check. But first I had to get off the dock, and as I found out, that's a pretty tough thing to do.

  1. Unlock SimQuarter
  2. From the Sim Quarter, we first have access to the river.
  3. Clip into that river.
  4. Pray that the game pre-spawns the fan boat, rather than either hiding or despawning it (OR find alternative clips otherwise)
  5. Use this early fanboat or clip set for hopefully massive cheese: -Start bayou early (skip chapter 3 story progress?!) -Start glasstown early (skip chapter 4 story progress/To Ending?!!), and definitely should give access to the cheat Ninja, which would allow for stat-boost routing

To spoil the fun, at the moment though, based on what I found and unless I missed something:

-Clipping the dock (or any dock) is not possible -The fanboat DOESN'T spawn early -And we're somewhat unlikely to find more clips of use.

But first:

Alternatively, a few notes about the Urbz movement system one learns when sprinting at docks in creative ways for a few days:

  • If you run with momentum into an NPC, you can activate your hoverboard to enter their physical model, which traps both of you in place, which continues after dismounting.

https://i.imgur.com/oJ48kHZ.png

-Being trapped in an NPC does not impart momentum to the player nor does it force the player or NPC out of position: they'll just wiggle in place underneath you. Your run is sufficiently fast to escape the overlap whenever you desire, at which point the NPC will return to their business.

  • An NPC will not take movement options that would pass through a player, and won't even go around them most of the time if the player is moving towards them. You can therefore move people around slowly by blocking off randomly chosen movement options you don't want them to take and nudging them in the direction you want them to go. Below is an example where Sharona was moved into the corner doing the above:

https://i.imgur.com/EZYHbH4.png

  • Pissing yourself appears to have no notable effects on collision or momentum besides halting it.

-Your motorbike has weird collision rules:

-- It will always spawn, when walking in from a new screen, with the front tire facing towards the top-right corner of the screen. This notably can makes for a 1-3 second micro-optimization over the course of a run by remembering to, when possible, to park your bike and follow paths where, immediately after leaving a building, such as the university, your bike does not need to move down and to the left, which forces turning time,

--Your bicycle only has collision when you enter a screen on which it was already sitting, and even then, only on the front tire and the colored portion of its front body. Otherwise, it's intangible, has no collision, and you can just walk through it.

-- When you ride the bicycle, you render it intangible, including this front body and tire portion, even if it was previously tangible, until you have an area screen transition. Talking and shopping are not sufficient to resolidify it, although warping with a genie lamp will.

-- If you warp back with a genie lamp onto the collision portion of your bike, you will render the bike intangible like above.

--If you ride your hoverboard, it will not render the bike intangible, BUT if you touch a collision segment of the bike when moving somewhat quickly on your hoverboard, it will make it intangible. Charging speed on a tangible motorbike by pedaling your hoverboard has no effect on the bike's tangibility

--Your bike's seat teleports to the position from which you mount it. This can pull the bike through walls. This incidentally can lead to some fun if you use the Nutria island river clip, IF you put the bike by the river on the dock's edge: you can pull it onto the river water and ride it! The below's a pic of the bike I pulled into the river:

https://i.imgur.com/LJiFVkz.png

You can go further with this Bike pulling glitch: if you take the fan boat into paradise island or the bayou and you parked the bike by the river's side, you can mount it on land, and therefore bringing the bike out of the river and into Paradise Island or the bayou.

If more glitches are ever found which find a use for doing this in an actual run, I want this move called "Bayou one-cycle", because it gives you access to one motorcycle in the Bayou.

Dumb jokes aside, although we can perform bayou one-cycle at any point after we have the fanboat, I don't think it has much utility, besides the standard vehicular "avoiding plants" your skateboard already does, and for putting your bike in the most inconvenient location possible. In terms of doing interesting things with the bike at the bayou, it seems you can't take the motorbike into any place you can't skateboard into.

For whatever it's worth, I had a lot of fun riding around in places I shouldn't with it though, and biking on the river is a ton of fun and possibly has its own glitches. I didn't probe too carefully with the bike, and encourage someone else to give it a try.

Some things that did not work for me for getting off the dock:

  • Running at its sides head on and wiggling (doesn't work)
  • Running at corners on the dock and wiggling (doesn't work)
  • Running at corners with people pushed into them and wiggling (Remember: NPCS, when you run into them, don't impart momentum nor do they push you out, they just obstruct forward progress, making it so you can't move) -Running at corners and waiting for an NPC to push you out (An NPC will not take movement options that would pass through a player) -Running at corners and talking to NPCS on the way (It seems it just pauses motion, it doesn't seem to change anything about the run you return to when you stop speaking)
  • Skateboarding in the crack created in corners with people pushed into them and pedaling (NPCS don't impart momentum, and doesn't work)
  • Running at non-dock corners in the Sim Quarter to try to clip through those and snake around (doesn't work)
  • Magic lamping into people on or near the docks
  • Sprinting at the sides and corners of the dock while mounting a board
  • Sprinting at the sides and corners of the dock milliseconds before pissing yourself
  • Motorcycling at it
  • The wedge-cycle: Placing the motorcycle in the corners, leaving and returning to the SimQuarter to render the bike tangible, wedging myself between the bike and the corner, and wiggling at the corner
  • The skateboard wedge-cyle: Doing all of that that and also repeatedly trying to mount your board. Pic included:

https://i.imgur.com/o0qhAWY.png

  • The bike-regrabbing wedgecycle: Do the wedge-cycle, and try to move the bike up to move the wedge with you by repeatedly regrabbing it every other move (Felt promising while you're doing it and the bike does move up a little, but the bike is grabbed at the position you're standing, and grabbing itdoes not impart momentum nor does it push you out. Plus, riding the bike renders it intangible.)

  • Repeatedly trying to mount a bike or skateboard while running or magic lamping away in the hopes it'll glitch up and use the momentum (didn't work for me)

  • For reverse dock clips, talking to someone on land from the water (Doesn't do anything)

Things that did work for getting off the dock:

  • Writing a bunch of action replay codes that let me set my XY coordinate.

Eyup, that's it.

If you want off the SimQuarter dock, no nutria clip needed, use the following code in sim quarter (you must enable-apply-disable-apply so you can move again:)

DOCK CLIP: From Simquarter onto water CODE: 02168710 00950000 02168714 03938700

REVERSE DOCK CLIP: From River onto SimQuarter dock CODE: 02168710 01050000 02168714 03808700

I've included a few other useful two way dock clips, so you can experiment with implications:

DOCK CLIP: From Glasstown Dock into river CODE: 02168710 02950000 02168714 00808700

REVERSE DOCK CLIP: From River onto Glasstown dock CODE: 02168710 02650000 02168714 00438700

DOCK CLIP: FROM Bayou into River CODE: 02168710 00950000 02168714 01138700

REVERSE DOCK CLIP: From River onto Bayou waterside CODE: 02168710 00950000 02168714 00938700

DOCK CLIP: From Paradise Island into River CODE: 02168710 00950000 02168714 02038700

REVERSE DOCK CLIP: From river onto Paradise island coconut challenge area CODE: 02168710 00950000 02168714 01138700

REVERSE DOCK CLIP: From River onto Paradise island cabana area CODE: 02168710 02150000 02168714 02838700

And in general, if you want to test the effects of a dockclip or other warps, throw this code in action replay:

02168710 XXXXXXXX 02168714 YYYYYYYY

and set the X and Y coordinates appropriately as whatever positive 8 digit hexadecimal number you want. If you're not sure how to do this, you usually can just guess a few times based on another warp until you get the warp you want, and if precision is important, just google "[your normal decimal number] hex" and it'll give you something to type in (but make sure you add padding zeros on the left side to make it 8 digits). In the game's coordinate system, +X is "More to the right side of the screen", +Y is "More towards the bottom", and the origin 00000000 00000000 is the area's top left corner.

IF USING THE CODES, REMEMBER: you MUST enable the action replay code, apply code, THEN disable the code-apply code so you can move again, because the above codes WILL fix your position in place until disabled.

I learned a few things with these clip tricks:

-No early fanboat was found. Maybe one of you can probe deeper and see if there's some way to trigger this (Talk to sleeping Gordy first? I never did in my run) but this was the biggest disappointment to me, because it means that even if we can dock-clip, not only do we need one dock-clip, we need several because we need to have reverse clips from the river to other locations we want to access.

  • Being trapped in a wall (Separate from NPCs, but ultimately frustratingly the same) does not impart momentum or push you out regardless of how close to the edge you are, it just impedes any forward motion.

This matches the behavior we saw with the bike and NPCS.

That said, if you're RIGHT at the edge of a wall but still inside, you can run out. A general principle I've found is: unless the distance you cover in one frame running is greater than the distance till you're out of the wall, you're stuck. Put another way: you generally cannot, using standard controls, naturally escape from inside a wall you didn't naturally get yourself into.

  • There are seemingly no other voids out of bounds in which a player can walk like the river: all the out of bounds inside and outside the map I checked is solid walls. This would mean even if we could clip into other non-river walls, this wouldn't help us much.

So, for example, If you see planters or fenced off areas that look empty just behind a fence (like near the hospital and university), or a solid bridge you might think you could walk on while riding the boat, I found for every point I checked that they are solid walls internally, do not be fooled. Example by the jail:

https://i.imgur.com/ecAbAVN.png

This is also true for the water on the top-right of the docks too: I found when testing that the above-dock water, it seems to be 100% solid walls.

https://i.imgur.com/dfzqBuc.png

And magic lamping doesn't desolidify these walls like the bike, sorry.

-All the above seemingly implies that you can walk on the river because the boat is you (equivalent to the way you on the motorbike is still you) is always supposed to be able to traverse it, and they simply never figured you'd escape from land to the water, probably because they heavily tested all the waterside docks and declared "Mission accomplished".

It further seems (speculation) that they didn't heavily test Nutria Island's collision like they seem to have done for all other waterfronts because in normal gameplay, you're there for all of six seconds, you need the speedboat to get there anyways, and it's easy to forget it's technically river-connected land. The unfortunate implication of that is that everything AROUND the river I checked, bayou dock, glasstown dock, and paradise island docks and shores, appear to be extremely solid wall that is fairly impenetrable.

  • Most unfortunately, the dock walls are incredibly thick along the bottom-left sides of the SimQuarter dock where you park the boat. I say thick in a moderately-objective sense here: you can warp a few pixels further in the bottom left dock walls than you could naturally reach several times, and each time you warp like that, you remain trapped in all directions: you can't run out of the walls.

The solidity of these docks is further increased because the area where the canoe to paradise island sits is solid wall, regardless of whether or not the boat is there. So, escaping out of the bottom right dock corner is almost entirely a nonstarter.

This means the only "weak" piece of the dock (even though it's still strong enough to resist every idea that I had) was on the bottom left corner, running left:

https://i.imgur.com/Wrhp9dA.png

In the above position, when you sprint into the bottom left corner of the dock, your X coordinate is at X=15.897 million (00EFA534).

To clip off the dock and escape running left, we need to get to X=15.289 million (00E94AA8), at which point I found our running speed is sufficient to get us outside the dock's wall in either direction, left OR right. The below warp code puts you in this position:

Dock clip Escape position SimQuarter: Warp Code 02168710 00E94AA8 02168714 0382D784

Numerically that distance sounds like a lot, and in one sense it is, because that fraction we need to pass through is a solid collision object.

Visually though? Try it yourself, these look SO FUCKING CLOSE to each other, it's almost literally less than one stride:

https://i.imgur.com/q7fXcuT.png

I want a creative person to find some way to get our character those 10 or so pixels left, because that's all we need for a dock clip, and whatever trick makes THAT clip work probably would work on other docks (didn't check 'em, but I have a suspicion that in the game's orthographic projection, any dock with a 90 degree 1 pixel corner like the SimQuarter dock (All of them) will likely have an equivalent clipping), which could have huge potential for more breaks.

So, what if we could dock-clip? For the sake of argument, on all docks:

-The Bayou is a bit fucked and I want somebody to explore this a bit more than me because I didn't want to replay the bayou.

A few things I found with the little I did, jumping in the moment chapter 3 began:

--You never get introduced to the brothers at the river, they're "normal" and act the same way they do after the Bayou is completed. --The brother's routine may be messed up somewhat. Greenshirt is in the house, but around 1AM, Redshirt Bayou Boo hangs out outside the tomb just like he's waiting for you before the sequence where he gets vamped, although he has nothing story related to say. --You can get the nightstick and talk to Lloyd, and he'll give you the locket in Chapter 3, but both Bayou Boo and Greenshirt will say "What do I do with a piece of junk like that?" if you try to give it to them, because your story progress isn't there yet. Further, the Red man never shows up, as that part happens after you give the locket to Boo. --If you get devoured by the plants, you get warped to the first area's hospital, NOT the bayou house. This may have routing potential.

It's all very strange, and I don't know what happens if you continue play to chapter 4 after the glitch and you're already holding the locket and have introduced yourself to Boo. Somebody should give it a check because I'd love to know what happens.

-Glasstown didn't seem to have anything notable happening, but I didn't check more deeply than running through it quickly: I want someone to check this too to see if you can early trigger endgame quests somehow, ESPECIALLY in the starting skyscraper, which I didn't even look in

-The cheat ninja works: she appears as she normally does at the carnival and sells stat and moneyboosting cheats as she normally does. This could be routing-viable statboosting, if we had dockclips

-Someone should check if Det Dann will open the tunnel for you with 100+ friendship after dockclipping the bayou, as I didn't check

-Going to an area early doesn't unseal the gates that block it off, at least from Glasstown-to-Simquarter (didn't check the other locations). So, there's no wall on the Glasstown side, but once you pass through the loading zone to SimQuarter, the walls are still there.

Last point:

I never saw anyone record it [EDIT: BTBSteve actually did it at the way end of the video and I missed it, but I'm leaving the section in so others can see the spot], but you can clip back onto nutria island in the river, though it's slightly harder. You run from the inside excape point slightly up for a frame and then move to the left. It's harder, but I've never seen anyone bring up getting back. The below's a pick of the clip spot which if you're running left or right, you'll pass through:

https://i.imgur.com/pTbjyqD.png

Walls seem to work very well; we can't currently clip out of the docks to do anything noteworthy with the river glitch.

If we could consistently though, with either an early fanboat or better clipping/speed tech, we get new statboost routing starting in chapter 3, we definitely can access a lot of broken story stuff with unknown consequences, and there may be other unknown cheese.

We need ways to run faster, and the 10% Xizzle run speed boost didn't seem to do it (although I didn't thoroughly test as thoroughly with it on, as I remembered it existed more than halfway through my testing). Clipping appears to be primarily determined by the size of your character's stride and whether the remaining segment of wall you're moving towards is thinner than that stride. Bigger stride size because we're moving faster? Possibly, more clipping possible.

I'd also like somebody to poke around with the above warp codes, explore harder, play through the game and be a lot more thorough about investigating the consequences of what happens if we could dock clip in terms of story progress and event progression during chapter 3, before the bayou, and afterwards once you've screwed with things. I did effectively no investigation into this.

I want to know what happens if you've ruined relationships with the redshirt Bayou brother to "I'm not speaking with you" terms Immediately BEFORE being teleported to the Bayou: I have no clue what would happen, would it break story progress?

I also would hope someone could duplicate my work, both on GBA AND DS, because I'm still really disappointed I couldn't get off the dock in-game and it might be a platform specific problem.

And lastly, if you read this far, thanks for giving it a read. It was a real nostalgia trip for me to mess with this game again, and although I doubt there's much interest in this type of over-analysis for a fairly underplayed 14 year old game, I really do think there's a lot of speed potential in this game, and I think either a consistent dockclip or access to early-riverboat would go a long way towards blowing the game wide open.

Edited by the author 5 years ago
walmarp likes this
England

Fantastic write up! I looked a little bit into the clip myself and came to a similar conclusion, but I went no way near in as much depth. My current hypothesis is that the game defines where you can walk rather than where you can't. Not sure how to go about verifying and testing this though.

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