Large scene scene in Unity, far bigger than one Terrain? - unity3d

Imagine a large free-roam game in Unity,
The yellow size indicates about the largest you can make a typical Terrain in Unity.
Art dept. will completely build, meter by meter, the entire scene.
Please note, this has absolutely no connection to repeating scenery (as in runners) or procedural scenery (as in say some race games).
Really, what is the correct and good way to do this in Unity?
use say 50 or so terrains, each perhaps 100m x 100m ?
can you even have or use that many terrains?
or what?
For anyone googling here.
The correct solution is indeed
Terrain stitching
that's it.
In practice you must use one of the tools available to do this (eg, TerrainFormer) or, your team will write from scratch a terrain stitcher.
Yes, you just use "many terrains".

The best approach to the exact problem posed,
is in fact to just:
"use lots of Terrains".
It seems to be perfectly viable in Unity to have many (dozens) of Terrain units, basically "sitting next to each other".
In practice, you'll need TerrainFormer
https://assetstore.unity.com/packages/tools/terrain/terrain-former-20052
or one of the similar tools.
(Or, I suppose, from scratch write your own tool to stitch terrains, and allow you manipulate them all at once, join the edge-heights perfectly, etc etc.)
It's not realistically possible to just perfectly sit many Terrains together (by hand), matching all the edges, etc etc. So you're going to need a "stitcher" package for putting many Terrain squares together.
So, this huge area ..
has about 12 Terrain.
So that's the answer, you can indeed have "many, many" Terrain in a Unity project, you do indeed essentially just "sit them next to each other". In practice it's not achievable unless you use one of the editor tools such as TerrainFormer.

The proper way to do this would have been with procedural mesh generation with MeshFilter and Mesh API but you mentioned that this not at all random or generative so that one is eliminated.
It's just simply a very long, thin, hand-made environment
The best way in this case would be a Modular Level Design. You need to create Modular Assets. With this you can have a long road in pieces which can be tileable. A good modeling artist should be able to create and texture modular assets with 3D modeling packages like Blender, Maya or 3ds Max.
All the programmer has to do is make each asset a prefab then use the Instantiate function to instantiate them to create any distance of environment. You can also create a static environment in the scene from the Editor. Almost anything can be made into a modular Asset especially buildings and roads.
After assembling them in Unity, you can do static batch on all the instantiated modular parts with Unity's StaticBatchingUtility.Combine to improve performance of the game since they are not being moved.
Below is an example of a modular road asset that can be used to create almost any amount of road:

You already answered your question
in this case would it be better to not bother with Unity's otherwise excellent Terrain, and the modellers would just outright build the long course/scenery? (Obviously you'd have to chunk it so it all occludes fine)
I think it's the way to go. If the performance is an issue, try putting each chunk in different scenes and then have a master scene to load them async and additively. And of course you want to unload each scene as it becomes invisible in the camera.
I personally go with your own solution which is letting the Unity Occlusion Culling system to take care of the hiding and showing chunks. I only go with the separate scenes approach if I'm not getting enough performance this way.

I recently had the same problem. We build a tilebased infinite runner with road crossings. The camera was positioned behind and over the car looking down on the street and the player car. So the setup is quite comparable.
We used Curvy from the Asset store to create paths for moving the player and also for creating the geometry of the streets and the surroundings among the streets.
https://assetstore.unity.com/packages/tools/level-design/curvy-splines-7038
It is also easy to spawn tiles with curvy paths and combine them at runtime. So you can separate long distances into smaller segments and spawn them randomly.
We also used QuickBrush from ProCore to quickly paint environment detail to the geometry like trees, bushes or stones. I think procore tools are now implemented in the new Unity 2018 version.
Worked quite well.

Related

Multiple Tilemap Maps Loaded Dynamically

Feel free to close this question if it is deemed too subjective. I realize that it might very well be, as it may focus heavily on best practices, which, if not an industry standard, may be subjective.
The Problem & Idea:
I'm using the tilemap system in unity (2D), and its been working great, but I have a few concerns regarding my particular usage. What I'd like to have is multiple "battle maps" that will get instantiated when the battle scene is switched to. My current idea is to just make each type of battle map a prefab (prefab on the grid, since the tilemaps are just layers), and then instantiate the grid when the scene loads in.
Is this best practice or is there any better way? Does having 10 maps vs 200 maps make a difference?
Other Things I've Considered:
Would it be a better idea to make one huge tilemap with all of the battle maps drawn a distance away from each other and just restrict the camera to moving only within the "current" battle map? The absolute max size I could see a map being is, let's say 30x20 tops, probably closer to half that though.
An earlier idea was to use small pixel map images to render the maps in. This was before I found out about Unity's tilemap system, which, admittedly, I'd rather use because it is so much simpler to visualize, and less work to develop.
The Scenario:
For simplicity's sake, let us assume the game has 2 scenes, the main menu, and a battle scene. Basically, the idea is to enter the battle scene and have a random battle map to be spawned out of what's available. The character(s) get placed, and any additionals also get placed, say, items, or what have you.
Is what I proposed above best practice? And should I consider any other other two systems I've also described? Or is there something I'm not thinking of that would be even better?
I don't believe that any of the above ways wouldn't work, I'm just curious if any of them is the best way to go about doing this.
Your consideration to have all of your battle maps drawn on a single tilemap and restricting the camera to only the region of the current map is an instant red-flag.
In my experience with unity, if I want to have a large level drawn on a grid I will have to break it up into chunks (each chunk is a separate tilemap) for performance reasons in the editor and in the game, so I would not recommend doing that.
If your goal is fast load times, then instancing a prefab as you suggested is not a terrible idea as long as the respective tilemap is fairly small (less than 10000 tiles), otherwise you would almost difinitely notice the map getting loaded in. If you are trying to load large tilemaps seemlessly, it may help to load the tilemap asynchronously before the actual switch occurs.
I would keep only the current map and next map loaded in the scene to ensure a seamless transition and optimal resource usage. Unity's tilemaps are not light.

Create planet with Terrain in Unity

I'm looking to create some procedurally-generated planets in unity. I'm not looking to make huge, realistic planets, but very small, walkable ones (like Super Mario Galaxy).
I've run into a problem though - Terrain objects cannot be rotated, so I can't really make a sphere out of 6 separate squares.
I've tried importing a hi-res icosphere with limited success. It's difficult to make look good (even with a high number of faces) when up close. There's also limited support on terrain-like features on non-terrain objects - like how to blend textures, add grass, or place objects on the surface.
I have seen a few unity store assets that do exactly what I'm requesting, so I know something like this is possible. I just can't figure out where to start. I've searched for nearly anything related to the topic and found nothing.
Thank you!
You can write a shader that will curve your flat surface, like this:
https://www.assetstore.unity3d.com/en/#!/content/26165
and here is base code:
https://alastaira.wordpress.com/2013/10/25/animal-crossing-curved-world-shader/
I have used it while ago and with upgrades it works well.

scnBox with scnTube through the middle

I have been digging around trying to find a way to show a game board of sorts.
It is basically a square board with a round hole in the middle, I am able to render the scnBox and the scnTube, but I would like the area where the scnTube sits in the box for the box to be transparent and see through the game board, but can't seem to find anywhere that has an example. Any help would be much appreciated. I am hoping that I am just missing something very simple, but this is my first time using scene kit.
Thank you.
Before Unreal Engine 4, (UDK and prior) Epic's modelling space was subtraction - a filled block was your game world and its extents. From inside this block you took chunks out to create space for players to run around in, and shoot each other. All's fair in love and war.
I'm telling you this because it's a good example of how contrived 3D modelling is compared to real world scenarios, and should (hopefully) put you at sufficient unease to digest what follows.
This approach of carving out of a finite block is still in Unreal Engine 4 and popular with older users, but it now defaults to an open, infinite world into which things are added. Most new users gravitate towards building into an infinite space of nothingness rather than carving space out of a solid, finite block.
Everything about 3D modelling is virtual, and virtually impossible to relate to the real world. Instead of thinking in terms of how things could be done if objects were real and literal, you need to think in terms of the limitations (and there are many) of geometry definitions as used in most 3D modelling and game engines.
The programming equivalent of this mental gymnastics is going from the concept of classes and objects to their realities within languages and frameworks. On the one hand the ideas and their ideals are wonderful, and on the other the realities are a bleak reminder that programming languages haven't really progressed very far, at all.
3D modelling is exactly like this. It's not much further along than it was decades ago, and is still using archaic ways to solve many of its original problems.
Cutting a nice, clean, efficient round hole in a cube is one such original problem.
A very simple shape is being intersected and cut by a shape with the potential for infinite complexity. What should happen? Should the simple become complex or the complex become simple? How to make the most graceful transition between the two?
That's the problem you're facing: a cube is a simple geometric shape, easily defined by minimal line segments. A cylinder introduces infinite possibilities for line segmentation around its circumference.
So somewhere along the lines of development, the architects of 3D modelling had to come up with a way to make these contrasting line complexities play well together for lightweight presentation on limited hardware. Their solution, in most cases, is a hybrid and a disaster of user operability, but masterful in its geometric efficiency: Polygon modelling, UVW unwrapping and subdivision!
All of which means that if you want to achieve this in the best way possible, with today's tools, for the purposes of Scene Kit, I suggest polygon modelling this board in Maya for 4 reasons.
It's got a 30 day free trial.
It works on a Mac
It's polygon modelling tools are second only to 3ds Max
It's easier to learn (for a complete newcomer) than MODO, and miles easier to learn than Blender.
MODO is interesting if you're already skilled in Polygon modelling, but it's so utterly discombobulating if you don't have that prior experience that I'd recommend using just about anything else first. Except Blender. Blender is free, but don't be tempted. It will cost you more in learning time than buying a copy of every other professional 3D app.
In MODO's favour, and the reason I mention it, it does export nicely for Scene Kit. I know that for a fact, but am not yet sure how well Maya exports for Scene Kit.
Which is the next problem you're going to come up against. All COLLADA files are not born equal.
New Maya does have Unity and Unreal export presets, so I presume it's possible to calibrate its COLLADA exports to match the demands of Scene Kit perfectly, just haven't yet needed to do it. This will (very likely) involve trial and error to get the settings right. It would be nice if Apple would tell us exactly how to configure export from all major 3D apps for Scene Kit, but instead they're giving us the half baked Model I/O, so we can double the effort of importing artwork.
All context aside (which has largely been to demonstrate that 3D is no simpler nor more refined than using an IDE and frameworks like Xcode and Cocoa), here's the meat and potatoes:
A video on one aspect of what's best to make holes, and starts out as you are, with a cube and a cylinder:
https://www.youtube.com/watch?v=zaEv5rio8bk
But it does presume a certain amount of Maya familiarity, some of which you can gain from this rather slow and ponderous examination of two other ways to make holes in cubes:
https://www.youtube.com/watch?v=lvMfoH5Ikrc
Yes, if you're counting, that's 3 ways to make holes. Actually four, because the first video starts with the boolean operation you might have been expecting to be how this could/should be done. In some parallel future we'll have well working boolean geometry operations. We're not there, yet.
Hopefully that same parallel future will offer us a programming language, frameworks and terminology that's not confusing and maintains metaphors long enough to make teaching easy and usage elegant and simple.
I dont know about that long answer but this can be achieved with Boolean Subtraction. You create a cube and a cylinder. You subtract the cylinder from the cube. In 3ds Max this is under compound objects-modifiers-boolean subtraction. I guess Maya has a similair function somwhere in the menus.

Terrain streaming in unity 3d

I am making an open world game and i want to know if there is a way of doing terrain streaming ( loading the terrain into mamory only if the player is close to it ) without using the LoadLevelAdditiveAsync function . i am using free version so this function is not available to me .
Don't forget as long as your terrain patches together nicely, you can always Instantiate terrain prefabs at run time.
Depending on how proficient you are at it, you can also procedurally create terrain at run time as well.
You can do it, and there are different ways to do it. I figure the easiest way to do it (but definitely not the most memory friendly) would be to define your entire level in one scene with multiple small terrains, using the TerrainStitcher tool to deal with seams. Then you could parent all objects under each terrain to a single transform, and use Instantiate to create/destroy them at runtime (in another scene). There are tools that take this approach a bit further, like this one.
But remember that in general big terrains in Unity aren't memory friendly and will reduce your performance. When using an endless terrain, where you don't care about defining the terrain before runtime you can reuse a few terrain objects and simply reposition them, but if you're designing them first, there isn't too much you can do other than lowering terrain settings like Pixel Error, and limiting details and grass.

Collision detection with images on the iPhone using OpenGL

I'm working on a 2D game (kind of like a top down space shooter) for the iPhone using an engine very similar to cocos2d (not exactly though) on OpenGL ES. I'm trying to figure out how I'm going to do collision detection.
All the ships for my game are images, and the game will load the image as a texture onto the screen. I've got very very simple detection going already that basically just takes the rectangles of the images and checks to see if those collide and can do that just fine.
But, of course the ship isn't perfectly taking up the entire rectangle so there is whitespace in there. So my question is how am I supposed to account for that whitespace? Do I have to have the matrices of the ships stored? Or is there another way? I've also heard of possibly using the Chipmunk physics engine for collision detection? How would that work?
(1) regarding Chipmunk, the short answer is yes you should immediately download chipmunk, donate something to the bloke, and start learning about it.
Working with that for a day or so will basically answer all the questions you have. If you want to work with physics games you're going to need to get in to it.
(2) you ask about using an approximation ("just" a rectangle) instead of something more accurately shaped like your spaceships. In fact, you'll be perhaps amazed to learn, that is precisely how it is usually done in all your famous big-name games you've played since we were all kids! Indeed sometimes you might use little more than A DOT (!) to detect collisions.
What you'd probably do in production is try a more complicated model, and play with it for a few hours and see, is it actually any better to play with than your simple dot or rectangle model.
If you do want to make a more complicated model -- just make one! Build it up from three or four rectangles using your current system. Try them "all against each other", and have "one big one to check first" to see if it is even anywhere near each other (sort of a simple spatial hashing).
You will find that when you do it with Chipmunk, which as you now know you have to immediately begin after reading this message, you just build it up the same tedious way. It's not a magic bullet. But if you were going to use a "more complicated model" yes it is better to go with something standard, chipmunk, to do the work in - it will get done quicker and better. There is heaps to learn and you should hop to it!
(3) Unity is not just for 3D Finally if you want to do it the smart-ass grown up way, you'd have to use Unity3D which will let you access the very metal, the Nvidia physics on the chipset. Note that unity works perfectly for 2D games also - you just click one button in unity to use a 2D projection (many brand-name ifone 2D games are done exactly like that).
If you use that approach, you can (if you want) have "absolutely exact" physics, with every nook and cranny of your model modelled.
What is the downside to doing this? Ah hah ... well the thing is, you need superb actual 3D models of all the stuff in your game! (Like you see them building in the "how we made the movie" special features that come with your favourite Pixar blu-ray.) To do that you need things like autodesk, maya and the like. you would quite likely buy some models ready-made from a digital prop shop (no need to build "a chair" as it has been done 1000 times already and you can buy one for ten dollars).
(Unity3D is completely free to use for a few months while you see if it can make you money.)
Incidentally on the Chipmunk front --- you can just use Corona which is ridiculously easy to use and has chipmunk-like physics completely built in with zero effort on your part! You could have the whole game done in less time than it took to write this email. You could be selling your game already and thinking up the next one. Or, you could use "Cocos" which indeed has a chipmunk-like physics library built-in .. personally (just me) I do not like and won't touch cocos - but of course many games use it.
(It seems pointless, to me, using cocos which is a "for idiots" product, when you can just go ahead and use Corona, which is a "for idiots" product but stupendously easier to use, 1000x more solid, and probably literally 10x faster to finish your product and start making money.)
Noel Summary:
So in some sense using Unity3D (and hence, the actual nvidia physics on your computer's chips) is the ultimate solution if you want detailed nook-and-cranny collisions. Going down one step, Chipmunk is exactly, precisely what you should be using on the ifone/ipad for 2D physics -- it is precisely what is used in all the famous games we know so well. You have a bit of learning to do so hop to it - it's superfun. Finally go right ahead and just make your current model more complicated if you wish - roll your own by adding more rectangles!
And the fourth point is, be sure to remember that in games, astonishingly, you can often get away with remarkably simple physics (often SIMPLER!! than one rectangle - just a damn point - ie, simply measuring the distance between centers!) Fifthly after going to all the effort of testing more detailed physics, you would play test one against each other, and find out what is the simplest physics you can get away with.