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    Slope Mods: A Brief Guide

    I was asked about slope mods by Dreadnought today. Halfway through replying to a PM, I realised this would be better posted here for all to see. If anyone can think of something I've missed, I'd be happy to consider it's inclusion at some point. For now though, this will just cover some of the basics.

    How NOT to build your Real Highway Networks

    What is a Slope Mod?

    A slope mod just adjusts the allowable slopes, at an individual network level. What does that mean?...

    Without any additional mods, if you have a big hill and draw a network, the game has a default setting for the maximum slope of each network. Maxis deliberately made this pretty unrestrictive, for ease of play. If you want to create more realistic looking cities, especially with hilly terrain, you will probably want to install a mod that adjusts the default slopes, making them more restrictive. This will help to avoid the bumpy uneven roads, that are very common when playing without such a mod.

    Each network in the game has it's own settings, that dictate how steep the slopes can be when dragging that network. These networks are:

    • Street
    • Road
    • OWR (One Way Road)
    • Avenue
    • Maxis Highway
    • Rail
    • Elevated Rail
    • Monorail
    • Dirt Road (RealHighway [RHW]).

    It should be noted that override networks do not have separate settings. So for example, if you are using the Network Widening Mod (NWM) or Street Addon Mod (SAM), which are overrides of the Road and Street networks respectively, they will use the same settings as the base network.

    Dirt Road is so called, because it was an additional unused network left in the game's code. Whilst it has been repurposed by the NAM team to be used for the RHW mod, technically it's the Dirt Road network. From here on in, I will refer to dirt road as RHW, for the sake of clarity.


    A Slope Mod sounds just up my street...


    Hopefully if you've made it here, you'll be thinking right now about installing a slope mod. As always with mods for SC4, there are far too many options out there to go into every one in excruciating detail. They all do pretty much the same thing, but there are two important factors you should consider when selecting one.


    1. What networks does the mod support/change.
    2. How restrictive is the slope.


    For example, you may decide you only want to have restricted slopes for some of the supported networks. So if a mod bundles everything together in one DAT, unless you know how to remove those you do not want, (really not very hard, even though it does require the Reader), you should be mindful of this.


    A very restrictive slope mod will totally transform how you build and terraform in game. Whereas a very unrestrictive mod, could end up looking like the vanilla experience. If you are new to slope mods, then it's probably best to try a few out and get a feel for how they affect things. Especially before you start using one in a cherished region. For example, a really restrictive slope can mean a 15m height difference, would take something in the region of a whole large tile for the slope. Obviously that's an extreme example, most of them are much more balanced for general play.


    For the purposes of this tutorial, I'm going to show the three mods I'm using:





    And here is a comparison shot, to give you an example of how these changes affect your slopes. Each of the networks in this picture are transitioning from a 15m high hill. Even with the slope mod by BRF, the street network takes only three tiles or 48m to descend by 15m. For math aficionados, that's a slope of around 1:3. This is pretty steep, but probably not completely unrealistic in some places. The road takes 4 tiles or 60m by comparison, which is 1:4. As you can see, I've cunningly laid these out from bottom to top, in the order of the slopes gradients. From steepest, to the shallowest slope. If you are still wondering why you need a slope mod, this picture should hopefully show you how much nicer your slopes can be.


    Note: I've used Rail stubs to indicate the first three tiles that are at ground level for each network. I've also used PedMalls to help see the slopes better. As you can see, rail has the most restrictive slope of all, so much so, even with my fairly reasonable grades, it doesn't fit in the screenshot.


    Using your slope mods more flexibly


    Whilst you could have multiple slope mods for a number of different situations, that's quite a complex setup and requires you to close SC4 and move files about. Let's say I want a road to have a slope similar to that of the El-Rail network shown above. Rather than switch to a slope mod permanently with those settings, there is an easier way. Just use the El-Rail tool to draw the slope first, delete it and drag the road down your nice new slope. Using the above picture as reference, you can do this for any network which appears lower down the screenshot, than the slope you require. To put that another way, if you made a slope using the Avenue tool, but then wanted to use it for the Rail network, this would not work. Since the rail network is more restrictive. Using this setup though, you can have quite a bit of flexibility for a number of networks. Note how the Rail networks, including Monorail and Elevated Rail, have the most restrictive slopes of all. That makes a lot of sense when you think about it, since in real life, the gradients they are able to support are much less than cars and other traffic are able to deal with.


    Some final hints and tips

    34785957734_3383d5fc99_o.jpgSim City 4 can be unforgiving at times, it's all too easy when making other changes, for your hard work creating slopes to become unravelled. Just as I have shown above, using PedMalls next to the slope, will lock-in the slope, making it impossible for development and other networks to alter them further.

    Of course, if you wanted a junction halfway down the slope, that now be impossible too. Here's where some planning really comes in handy. Using the four steps shown on the right, you can easily form intersections as part of your slopes.

    1. Drag the initial slope, here I am using the El-Rail tool for the slope. I have placed pedmalls and used a rail stub to completely flatten the tile where the junction will be.
    2. Now you can continue to drag your slope, in this case in two directions, from the stub.
    3. I've placed the pedmalls here before I built the road. As you can see, the slopes are working very well.
    4. Lastly, I've dragged the street tool, anything with a less restrictive slope would do, parallel to the new road. This makes the surrounding tiles match the slope used for the road. This is useful if you want to zone next to the road, or sometimes for blending into the terrain better.

    Note: I have not dragged next to the road junction, a gap of one tile must be left here. Because I've used pedmall to lock-in the slope, there would be no danger of messing up our hard work. But if the pedmalls were not present, dragging either of the parallel streets closer to each other, might mean you'd have to start over.

    Another useful thing to know, when zoning next to slopes, the game can actually alter the slope of the transit network. Either when zoning or when buildings develop. Often this is quite undesirable, but there is a way to avoid it. By holding the CTRL key when zoning, the game knows not to change the slopes in either scenario. It does require some thinking about how you zone each area, but is a very handy way to stop the game messing up all our hard work, to keep slopes looking good.

    If you make a partial slope, you can then level off areas using "stubs" as required. Stubs are made by clicking only once with the network tools, such as the Street, Road or Rail, in each tile. As opposed to connecting or drawing them in a line. I prefer to use rail stubs myself, because they do not feature auto-connect. This can catch you out on occasion, causing problems, especially when using the RHW or Streets tool.

    Leave these stubs in place whilst you are building your slopes, to incorporate many different things, that might otherwise look undesirable on uneven terrain. This can be especially useful for incorporating WRC's, TE connections and many other possibilities into your slopes.

    User Feedback

    A follow-up article might someday talk about the other parameters in a slope mod. Besides steepest slope, there's also how much the slope is allowed to change from square to square, and how much the game is allowed to raise or lower terrain before giving up. There are also parameters for deciding when to tunnel or bridge, and then there are the costs of all these things.

    Once one learns how many ways a slope mod can affect both aesthetics and practicality, one may be drawn into downloading a comprehensive slope mod and (in one of the editors) customizing its parameters to suit one's own playing style.

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    u still get a ... terrain not suitable (red out) message while trying to place roads or streets ... do that above method ?

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