When launching up the editor, the first thing I wanted to do was make an outdoor area, since I've already mastered dungeon creation. However when attempting to do anything, I failed because of how difficult it was to understand. I've seen a few people having this issue, and there is no in-depth official explanation on how to do this except for a few helpful tips here and there on the forums, so I'll try my best to clear up everything I've learned so far, as well as some tricks in the editor to make cool stuff
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If you would prefer video, Skuggasveinn has a great video series that should explain everything here: viewtopic.php?f=22&t=7055
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The Very Basics of Outdoor Levels
| Getting a sky
If you've tried making an outdoors level before, you've probably run into a black screen with whatever elements you've placed, and it made no sense. I did the same. To fix this, the first thing you need to do to make an outdoors enviornment is to define which area of your map should be outdoors. You'll want to search the object menu (2nd tool, +) for sky, it will look like a gray circle. Choose the sky that best suits the area you are creating; if you're making a beach, the forest sky should work fine. When you have the sky selected, place it anywhere in the map, preferably in a corner where it won't be in the way, since the editor treats sky items as a dungeon item (the object themselves are invisible, however).
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| Making the grass grow and natural terrain (heightmap tutorial)
Now that we have a sky, if you were to start your map, you have a beautiful sky... that mirrors itself halfway down the screen. Let's fix that. Go to the tile menu (3rd tool, grid) and search up the tiles you'd like to use. I'm using a forest for tutorial purposes, but a beach tile should work the same way. You'll probably want to cover the whole map with the tile, so select the tile you want with either the left or right mouse button (you will see it display at the top, no memorizing required), then hold shift and use the left or right mouse button to place the tile selected on the corresponding button. Viola, you now have covered your map in a tile. However, if you launch a preview you will still not see any change, this confused me for a long time as well. What you need to do is search the object menu for a heightmap tile. This will look like a pressure plate. You can also place this in the corner, you don't need it anywhere specific (like the sky), and it is invisible. As soon as this is down, your grass will appear!
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And now we get to a slightly more confusing spot. Have you ever wondered what the use of the dropdown menu is on the tile menu? Well at the moment I've only discovered uses for the tiles and heightmap, so we will go over the heightmap part.
Now that you have the heightmap tile placed, go to the tile menu and select heightmap from the dropdown menu. Your level will be covered in a hard to see gray overlay, you will be totally okay with this in just a moment. At the top, there is a height adjuster, use the arrows on this to select a value from -3 to 3. Negative values dip the terrain (dark squares) and higher values raise it (light squares). Simply choose the one you'd think will make your map look best and start painting areas with it. You do not need to coat the entire level in heightmap, only the area you want to rise up. After a bit of painting, your level will look like this in the heightmap:
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| Just add water
Water may be one of the trickier parts of this guide to figure out on your own, but I'll make it simple. First, grab an underwater_ tile from the tile menu, and make sure you set it's floor to -1 so that the party can actually fall into it. If you wanted a waterless ditch for a custom map (ideas!), that's all you need from this part! If you want to get a moat for your castle, you'll just need a bit more. Go back to the object menu and search for water. You'll get a bunch of surface options, so choose the one that matches your enviornment; it's basically just color difference. Place one of these items anywhere in your ditch, and make sure the height is the floor that the water comes up to. For example, if the main floor is 0, you want the height to be 0 unless you can drop down to a lower floor and still not be in water. Once you have done this, you are all set with beautiful water physics
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Note: If you don't surround your water with tiles, any ceiling that your water tiles have will go up, resulting in the water tile wall rising above the water. You may or may not want this depending on what you're going for. Just make sure to surround your water with the tiles you want.
Advanced Outdoor Items
Buildings
| Guard Post
This is going to be tricky, as you can see the final product in my upcoming map (no shame here). Also note that this is all done within the vanilla editor.
Editor View:
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Result:
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I experimented with, and possibly bent, a lot of editor options in order to create this. Luckily it turns out looking decent, but if I find something that looks better, I'll fix this. And without further ado, let's begin.
We're going to start by coating a small 5 square '+' sign--or you can coat more if you wish, this is to allow the player to look over the tower--in a 1 floor, 2 ceiling grass tile; or choose whatever tile best suits the enviornment--just note that using any kind of dungeon tiles will spawn walls that look really bad, stick with outdoor tiles. Next we'll select a castle_wall--the numbers give it more decay if you need it--and then place 4 surrounding the middle square. You'll need to do this again, but each wall must be facing the opposite direction of the other on top of it. Otherwise, you will have see-through walls that don't look very good. Next, you should grab some pillars, and place them at the corners of the tower. If you've kept up well so far, it should look like this:
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And now that the core tower is complete, we'll begin on what gives it purpose. Start by adding your choice of a ladder to the side you want players to climb up, and make sure the ladder is on the correct height, although this probably won't be an issue. Then go back to the tile menu, and select void. This is the best way to create an area that doesn't get an appearance while still giving a dungeon room to add details. Think of it like creating the tile for the editor. The only tile that will get the void will be the center tile; make the floor 0 and height 2. Once this is done, place a castle_floor right in the center. And this is where it may get a little tricky, since we're going to pile multiple assets on each other. As added detail that probably won't be seen, I added crates at the bottom of the tower--the little things, right? After this, I like to place a castle_bridge_grating on top of the crates, and make sure to set the grating's height at 1. At this point your tower should look a lot like this
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Now that the initial purpose is finished, we can continue to add objects that make the post look more important, like a lever for controlling doors, or a lantern for the appearance of safety in the dark. If you want a lantern, take whichever non-torch light source you want, and place it in the middle of the tower, giving it a height of 1, since any higher hardly has an effect unless you place a lot of these to add to the strength, since lighting is apparently weaker in this game. Make sure you take off the model and particle on the lantern, because you can't get it at the right height to look good at all. Next, place another pillar on top of the rest, and one on each corner a height of 1. Lastly, take another castle_bridge_grating and place it in the middle with height 2. Although not perfect, your guard post now has a decent roof. I couldn't find a better way to do this, castle objects don't line up well outdoors. And for the last part, we're going to add a lever so a gate can be raised, or whatever else you'd like to do. Take a beach_wall_text and place it in the middle with height 1, along with making it on the side you want it to be on. Then, take a lever and place it right on the beach_wall_text with height 1 as well, and there you have it, a functioning guard post!
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If there's something that needs to be cleared up, I'll add another section onto this post.
I hope this helps, thanks for reading!