Trying to recreate a complex interchange. Seems impossible. Any pointers?

[GeauxWave 19]

I got back into SC4 recently after about a 5 year hiatus, and decided to recreate the city of Pensacola, FL. First, I'd like to say thank you to everyone who has put work into creating the NAM and all the other great mods. This community has truly made SC4 a timeless classic of a game that is so much more fun than it ever could have been on its own! 

I have a lot to catch up on with the NAM and the new FLEX functionality especially, but I've been struggling on how to even approach the challenge of creating this termination of Interstate 110 in downtown pensacola (see attached for the google earth image). It has a weird curve at the the end, but I am totally willing to forgo that bit of realism. I have some room to the west to work with (see attached map with green box overlay). I think the bigger challenge is the convergence of the rail lines and tram network (the streetcars were disabled in the 1930s, but I want to bring them back!). I understand the game has limitations, but I was hoping you guys could help point me in the right direction as to where I will need to make compromises. I feel like, at a minimum I will need to push the two GLR East/West lines to the north (3 blocks) and south (2 blocks), right? What should I do about the rail though? Can I even run the ramps over the 8x8 90 degree turn? Can I do it over diagonal rail? Or should I just run it north prior to the highway and then cross it over north of the ramps? I'm hoping to keep things as close to reality as possible, but like I said, I know the game has limitations and I'll need to make compromises.

Thanks in advance for any guidance you can offer. Even if it's just, "no way that's gonna happen". At least then I'll stop spending time trying to figure out how to do it, LOL.

Google maps link.
 

 

[rsc204 21,806]

Generally speaking, no networks can intersect during curves, FA sections, on/off ramps or height transitions. FlexFly exists specifically for RHWxRHW connections, excluding RHW-2 and with the limitation it can only cross one other RHW network Some other exceptions where specific pieces exist occur, but I don't have an exhaustive list.

For maximum stability, use Flex/Draggable ramps (DRI) wherever possible. If you've not used RHW for 5 years, it's a different beast and the possibilities are hugely expanded since NAM33 especially. See this link for YouTube video tutorials that will show you how the DRIs work:

I'd build (plan) things in this order):

• So you'll want to use FlexFlys for the crossover of the highway, work out how to space those so they work first, since everything will need to be built around their placement.
• The Rail should be fine if you find a suitable diagonal tile or two where running it under the highway. You can use 45 degree curves on either side so it shouldn't look too different to the real world. Assuming you've RRW installed, check the FlexTrack PDF, found here:
  \Documents\SimCity 4\NAM Auxiliary Files\Documentation\old\RRW FlexTrack User Manual.pdf
  Plenty of different radius WRCs exist, including WRCs branching from switches too. But this functionality is limited for RRW users only.
• Likewise, you may find the Tram/GLR lines will fit, but support is limited, I know OxO connections all work, some diagonals may too. Experiment in a blank tile by dragging various combinations. If you get a red error box, there is no code to support the crossing.

Other than that, I don't see anything impossible here. Often I find it useful to play on RHW intersections in blank tiles, it helps to get a feel for how to go about it before attempting it in the real location.

[GeauxWave 19]

1 hour ago, rsc204 said:

Generally speaking, no networks can intersect during curves, FA sections, on/off ramps or height transitions. FlexFly exists specifically for RHWxRHW connections, excluding RHW-2 and with the limitation it can only cross one other RHW network Some other exceptions where specific pieces exist occur, but I don't have an exhaustive list.

For maximum stability, use Flex/Draggable ramps (DRI) wherever possible. If you've not used RHW for 5 years, it's a different beast and the possibilities are hugely expanded since NAM33 especially. See this link for YouTube video tutorials that will show you how the DRIs work:

I'd build (plan) things in this order):

• So you'll want to use FlexFlys for the crossover of the highway, work out how to space those so they work first, since everything will need to be built around their placement.
• The Rail should be fine if you find a suitable diagonal tile or two where running it under the highway. You can use 45 degree curves on either side so it shouldn't look too different to the real world. Assuming you've RRW installed, check the FlexTrack PDF, found here:
  \Documents\SimCity 4\NAM Auxiliary Files\Documentation\old\RRW FlexTrack User Manual.pdf
  Plenty of different radius WRCs exist, including WRCs branching from switches too. But this functionality is limited for RRW users only.
• Likewise, you may find the Tram/GLR lines will fit, but support is limited, I know OxO connections all work, some diagonals may too. Experiment in a blank tile by dragging various combinations. If you get a red error box, there is no code to support the crossing.

Other than that, I don't see anything impossible here. Often I find it useful to play on RHW intersections in blank tiles, it helps to get a feel for how to go about it before attempting it in the real location.

Thank you! This is all extremely helpful, and exactly the guidance I was looking for. Man, that video is gold. I experimented a little bit just now, and I think I'm starting to get the hang of it, starting to see a light at the end of the tunnel. I'm excited, but I have to call it a night. I will work on it more in the morning, and report back. Thanks again!

[rsc204 21,806]

As is often the way, I saw the general layout and took it as a chance to try out something different myself, I came up with the following:

Granted, it's not perfect missing the GLR for one and you may want to optimise the placement of some things, but it should help you see some important design constraints. I've marked the key pieces used, the purple road crossing has just one place it can go, so start with this part of the E1 ramp/FlexFly and work from there. The left side is pretty loose, because I like to build RHW with lots of space and make the city work around it. But there are ample ways to tighten this up for a more compact setup, take care of the green dots, if you do move the interchange, you'll need to adjust the placement of these height transitions. I elevated this part over the Rail/Road, because RailxMiS is not supported as a valid crossing, attempting this will elevate the rail network. You could use a section of NWM OWR1 to get around that, but only at ground level, however OWR-1 transitions to MIS with ease (drag them together).

Other than that, I think it's pretty close to what you were after. I certainly enjoyed the challenges building this presented. I think you'll need to be flexible with other roads/streets in the main interchange area. GLR could be added, but a Tram in Road networkxRHW might be a sticking point, whereas GLR on it's own is more likely to work. I did manage to get a Tram in Road section all the way from the T-Junction South of the Purple dots all the way through the interchange. The key there is remove the MIS sections with the RHW Disconnector, drag a road through, then click each tile with the El-Rail tool. This converts road to Tram in Road and the MIS will "jump" across it automatically. I did have to move the leftmost 2-LVL Height Transition to fit it in, but there is space for it. Only OxO TiR is going to work however and if you used the Puzzle Pieces, RHW will not interact with it.

I've switched the over/underpasses, because it helps the design fit better, so I'd stick with that change too.

21 minutes ago, GeauxWave said:

Man, that video is gold

Just to be sure, it should be a playlist with about 11 videos, but yes they really are very handy. 

[GeauxWave 19]

Still learning and working on this, but I thought I would post an update. That video playlist has been so helpful. And I can't tell you how helpful your example build has been to me. Thank you very much for taking the time to do that! 

I'm staring to get a hang of the draggable ramps. Very cool stuff once you learn the patterns. I was able to make the number of lanes match perfectly to the real thing, and was even able to keep the old train station in its original spot, which I never thought would be possible.

I threw the default convention center in there for now, but will definitely be looking for a better/closer match to the real thing.

Have to take a break for a bit, but will post another update when I can work on it more.

 

[GeauxWave 19]

Okay, I think this is about as good as I can make it for the time being. It's far from perfect, but I'm pretty happy with how it turned out. It's certainly better than what I thought would be possible!

I still need to figure out how to connect that one ramp in the southeast corner, and of course, put in the GLR . 

 

 

 

[GeauxWave 19]

Another update... I was able to curve the southbound exit! It's a pretty sharp turn at the bottom of the ramp, but that was as far as I could push that 2-level height transition piece. I think this is now as close to the real thing as I will be able to do, and I'm very pleased with how it turned out. Big thanks to again to you, rsc204! 

The streetcar lines are in too. I just converted them to subway to bypass the mess, haha. They were discontinued in the 1930's anyways, so this is more of a fictional reality. Let's just say they installed the subway system when the interstate was built.

I'm still trying to figure out how to merge in that MIS lane that curves behind the convention center though. It keeps trying to convert the HWY to RHW-2 or RHW-4 in the opposite direction. I'm starting to think it's a lost cause.  I hope not!

[rsc204 21,806]

4 hours ago, GeauxWave said:

I'm still trying to figure out how to merge in that MIS lane that curves behind the convention center though.

You'll need a B1 Inside ramp, if you get it lined up right, you could go diagonal right from the ramp, but it's easier to remove the parallel MIS before drawing said ramp piece. See this handy reference for how to draw the inside ramps, they are a bit unique. If your problem is they convert to the wrong ramp types when initially drawing the branch, that simply means you need a tile more space to place it correctly.

Personally, I've a lot of tricks for placing things closer together, for the most part it comes down to the order of placement. But for example with height transitions, you can use the RHW disconnector to remove say an avenue piece, plop the transition which will now place "inside" the avenue, then re-draw the avenue once the RHW is in place. Another tip, often things may seem unstable, but with a bit of coaxing you can get them to play nice, one or two parts of the following suffered from this, but the increased stability comes from starters in ramps/flexflys and such pieces. Sometimes it's necessary to temporarily remove an entire stretch of RHW or use some starters during building too, to prevent the wrong width of RHW from appearing. 

4 hours ago, GeauxWave said:

Another update... I was able to curve the southbound exit! It's a pretty sharp turn at the bottom of the ramp, but that was as far as I could push that 2-level height transition piece. I think this is now as close to the real thing as I will be able to do, and I'm very pleased with how it turned out. Big thanks to again to you, rsc204! 

I've taken another stab at this, forgoing the E/W OWR3 through the interchange (a minor compromise given the avenue crossing above it), I managed to even use from FA-RHW MIS to make this look really good (IMHO):

But, with a more conventional setup, there is space to get that through by moving the leftmost MIS height transition. Once more the "key" from before applies to this image. Note specifically the bits in Purple, related to the rail. One of the quirks of RRW, it doesn't offer such clean curves adjacent to networks, because only wider radius curves were supported from the get-go in favour of realism. I've done one better here, using an R2 curve, of course that takes the rail one tile away from the avenue. But, flip the station 180 degrees, you should fit it in facing the avenue, instead of the road. There are 6 (small purple dots) tiles to fit any such station available, but you could adjust that. Lastly, the purple arrow shows where to finish dragging the rail pattern, do this and you'll get a nice smooth S-Curve to put the rail back where you want it. Finally, note I dropped the RHW down to L1 to facilitate a more compact interchange.

[GeauxWave 19]

5 hours ago, rsc204 said:

You'll need a B1 Inside ramp, if you get it lined up right, you could go diagonal right from the ramp, but it's easier to remove the parallel MIS before drawing said ramp piece. See this handy reference for how to draw the inside ramps, they are a bit unique. If your problem is they convert to the wrong ramp types when initially drawing the branch, that simply means you need a tile more space to place it correctly.

Personally, I've a lot of tricks for placing things closer together, for the most part it comes down to the order of placement. But for example with height transitions, you can use the RHW disconnector to remove say an avenue piece, plop the transition which will now place "inside" the avenue, then re-draw the avenue once the RHW is in place. Another tip, often things may seem unstable, but with a bit of coaxing you can get them to play nice, one or two parts of the following suffered from this, but the increased stability comes from starters in ramps/flexflys and such pieces. Sometimes it's necessary to temporarily remove an entire stretch of RHW or use some starters during building too, to prevent the wrong width of RHW from appearing. 

I've taken another stab at this, forgoing the E/W OWR3 through the interchange (a minor compromise given the avenue crossing above it), I managed to even use from FA-RHW MIS to make this look really good (IMHO):

But, with a more conventional setup, there is space to get that through by moving the leftmost MIS height transition. Once more the "key" from before applies to this image. Note specifically the bits in Purple, related to the rail. One of the quirks of RRW, it doesn't offer such clean curves adjacent to networks, because only wider radius curves were supported from the get-go in favour of realism. I've done one better here, using an R2 curve, of course that takes the rail one tile away from the avenue. But, flip the station 180 degrees, you should fit it in facing the avenue, instead of the road. There are 6 (small purple dots) tiles to fit any such station available, but you could adjust that. Lastly, the purple arrow shows where to finish dragging the rail pattern, do this and you'll get a nice smooth S-Curve to put the rail back where you want it. Finally, note I dropped the RHW down to L1 to facilitate a more compact interchange.

 

You're amazingly helpful. I've saved that DRI drag patterns table for future reference. It's crazy how complex some of these techniques are, but I imagine they start to become more intuitive with practice and the more one understands how it works behind the scenes.

Here's a GIF of the pattern I used to create the ramp. It took me a while to get because I didn't realize I needed to expand the width to MIS-2. I kind of stumbled into that by accident, lol. The key was knowing about about having to use the disconnector and re-dragging. But like you said, it often takes a bit of coaxing and finding the exact pattern and order of steps to make things work. I actually find that to be a lot of fun.

[rsc204 21,806]

At it's core is a set of repeatable steps for A/B or D/E ramps, but insides are a bit more complex. But if you use them enough, the patterns become pretty memorable, although the FlexRamps option is there to cover the basics, this is quicker than flicking through menus. Glad you've got it all working, like I said, it's an interesting setup for an interchange, not the sort of thing I usually build since I tend to make European cities. So it was nice to break out the RHW and do something different, I too enjoy messing around solving these problems.

[GeauxWave 19]

Made some improvements to the Southbound curves. Looks much better now, and pretty darn close to the real thing IMO. I think I'll leave it at this, and start building the city now. I knew this was going to be a beast, so I wanted to tackle it first and then build up around it. Thanks again for all the help!

 

 

 

This is the overpass just a few blocks north of what we just built. I need to do a lot of research before diving into this, but I'm sure I'll have more questions then.  (will start a new thread)

[matias93 7,535]

5 hours ago, GeauxWave said:

This is the overpass just a few blocks north of what we just built. I need to do a lot of research before diving into this, but I'm sure I'll have more questions then.  (will start a new thread)

Strangely enough, this looks much more doable, specially if you don't mind some small differences on turning lanes that will be possible only with NAM 37 or superior. Also, I would recommend you to stay on this thread

[GeauxWave 19]

16 hours ago, matias93 said:

Strangely enough, this looks much more doable, specially if you don't mind some small differences on turning lanes that will be possible only with NAM 37 or superior. Also, I would recommend you to stay on this thread

Glad to hear that! I don’t mind small differences in the turn lanes. 

And no problem on keeping it in this thread. I actually prefer that, but assumed I should make another one because it may be too far off topic. 

[GeauxWave 19]

Just to confirm, it’s not possible to run road under a flexheight ramp, right? I could have sworn I had it that way previously, but after about 100 attempts I’m not able to do it again. The ramp keeps breaking if I run the road after placing the ramp. I’ve also tried the disconnector, dragging the road through, then dragging RHW along the ramp, but that totally breaks. 

[matias93 7,535]

No, nothing can go over or under a ramp or height transition.

You have options, though. You can make the road go around the ramp, to move the ramp back or forth to give space to the road, or you can use a tunnel. For the game, tunnels go under everything and give you infinite extra layers if used wisely.

In this case, you could make a 3 wide tile earthen ramp and to cross it under with a road tunnel, but you would need to match the heights of both the ramp and the minimum tunnel clearance, so maybe the only way would be to build a hump ramp of sorts.