I am trying to create a solver for a puzzle in a web game. The simplest explanation is, I have a 2d grid where visiting each tile and consume different amounts of 2 resources and if either reaches 0 then the path is invalid.
I was trying to use dijkstra's algo to build this but was having trouble because to get to each node you don't know if spending more of one resource will allow better paths in the future.
I've tried to just check all paths with some optimizations but that takes too long even for fairly small boards.
Related
Working on a recent project I wondered how to find a good/perfect path to a target that is moving with a steady speed. I tried standart A* pathfinding but it failed, since the heuristic will be wrong the more the object moves and I just can´t find a way to make that work for me. Maybe you guys got another algorith that should work with just fine or some calculation tuning with A* that would work...
Thanks for your afford :)
A* should in general work, but then of course you need to recalculate every time the target moves. For 99% of cases, this is actually ok. For example, in video games you can get away with only recalculating the best path once every second or so, so it's generally not a huge performance hit.
However, if you really need something more powerful, check out Generalized Adaptive A*, an algorithm specifically designed to handle moving targets. And if you really want to be on the bleeding-edge, there are multiple adaptations of GAA* that are faster in certain cases - see this post (under "moving target points") for more details.
Using A* with a moving target is ok, but you must recalculate the whole path again. I don't think A* likes just having it's destination / goal changed.
Your A* needs to be very well optimised to run in real time and recalculate the new path every time the target moves.
Remember to play with your H to get a balance between working out the shortest path and the quickest to calculate. All depends on your map and obstructions really.
However A* may not be the best path finder for your application, but I'd need to see your map and more info..
I've been looking for a robust method of pathfinding for a platformer based game I'm developing and A* looks like it's the best method available. I noticed there is a demo for the AStar implementation in Godot. However, it is written for a grid/tile based game and I'm having trouble adapting that to a platformer where the Y axis is limited by gravity.
I found a really good answer that describes how A* can be applied to platformers in Unity. My question is... Is it possible to use AStar in Godot to achieve the same thing described in the above answer? Is it possible this could be done better without using the built in AStar framework? What is a really simple example of how it would work (with or without AStar) in GDscript?
Though I have already posted a 100 point bounty (and it has expired), I would still be willing to post another 100 point bounty and award it, pending an answer to this question.
you could repurpose the Navigation2D node for platformer purposes. The picture below shows an example usage. The Navigation2D node makes it possible to navigate the shortest path between two point that lie within the combined navigation polygon (this is the union of all NavigationPolygonInstances).
You can use the get_simple_path method to get a vector2 array that describes the points your agent/character should try to reach (or get close to, by using some predefined margin) in sequence. Place each point in a queue, and move the character towards the different points by moving it horizontally. Whenever your agent's next point in the queue is too high up to reach, then you can make the agent jump.
I hope this makes sense!
The grey/dark-blue rectangles are platforms with collision whereas the green shapes are NavigationPolygonInstance nodes
This approach is by no means perfect. If you were to implement slopes into your game then the agent may jump up the slope instead of ascending it normally. It is also pretty tedious to create all the shapes needed.
A more robust solution would be to have a custom graph system that you could place in the scene and position its vertices. This opens up the possibility to make one-way paths and have certain edges/connections between vertices marked as "jumpable" only. This is a lot more work though if you can not find any such solution online.
I am trying to load a very complex set of GLTF models in AFRAME.
My problem is very simple; my goal is to try to load about 9 million of gltf models in a unique scene.
My idea was to combine different level of detail in GLTF models depending on the camera distance and also only load those gltfs which are visible by the camera. If not the problem is that the assets are loaded in memory and my browser gets finally hung due to memory consumption.
Is this possible in AFRAME?
With some attention to A-Frame best practices, you should be able to make a performant scene with tens of thousands or even hundreds of thousands of polygons. But it will not be possible to load millions of distinct glTF models simultaneously in A-Frame, or any WebGL renderer for that matter.
Assuming you just want to show as many as models possible, try to take advantage of certain special cases:
If you need to render many copies of the same model, you can use a technique called "instancing". Check out aframe-instancing for some example code on how to do that. Depending on the complexity of your model, you may be able to show thousands (but probably not millions) of copies at once.
If you're making something like an RPG — which needs many things in the world, but only a few are in sight at any given time — then you can be clever about dividing your world into zones, and only loading models for the current zone.
Both of these are non-trivial to implement, and beyond the scope of a Stack Overflow question. My suggestion would be to try to get started on your own, and when you run into trouble, post new questions with the minimum amount of code necessary to see what you're trying to do. You may also find the A-Frame Slack group to be useful.
I'm making an online billiard game. I've finished all the mechanics for single player, online account system, online inventory system etc. Everything's fine but I've gotten to the hardest part now, the multiplayer. I tried syncing the position of each ball every frame but the movement wasn't smooth at all, the balls would move back and forth and it looked "bad" in general. Does anyone have any solution for this ? How do other billiard games like the one in Miniclip do it, I'm honestly stuck here and frustrated as it took me a while to learn Photon networking then to find out it's not that good at handling the physics synchronization.
Would uNet be a better choice here ?
I appreciate any help you give me. Thank you!
This is done with PUN already: https://www.assetstore.unity3d.com/en/#!/content/15802
You can try to play with synchronization settings or implement custom OnPhotonSerializeView (see DemoSynchronization in PUN package). Make sure that physic simulation disabled on synchronized clients. See DemoBoxes for physics simulation sample.
Or, if balls can move along lines only, do not send all positions every frame. Send positions and velocities only when balls colliding and do simple velocity simulation between. This can work even with more comprehensive physics but general rule is the same: synchronize it at key points. Of course this is not as simple as automatic synchronization.
Also note that classic billiard is turnbased game and you do not have all the complexity of players interaction. In worst case you can 'record' simulation on current player client and 'playback' it on others.
I'm making a two player 3D game, and need to synchronize the location of the remote player. Only one object, the avatar representing the player, needs to be synchronized between the two games.
I thought this would be pretty straight forward, but it turns out even in a local network the remote player is moving in a stuttery way when playing on two different machines (two instances of the game on the same machine looks fine).
In the current approach one game is the server, while the other acts as a client, sending coordinates as text strings over a dedicated port. They are basically streaming avatar coordinates to each others, each time the avatar is actually moving.
Any idea how resolve lag related issues when sending/receiving coordinates? Only needs to work over a local network.
Glenn "Gaffer" Fiedler's series of articles on Networking for Game Programmers are pretty much the go-to guide for basic game network programming. He also has an article on Networked Physics.
Many of the techniques described in that series of articles (eg: reliability) are already implemented for you in libraries like Lidgren.
Basically the techniques you want to use are interpolation, extrapolation and prediction. There's a good explanation of them in this article in the aforementioned series, plus the Networked Physics one. Basically you take the unreliable, laggy stream of position data, and use that to make a visually plausible estimate of the actual path of the object.