Questions tagged [game-loop]
The central code loop responsible for handling the running gameplay. At its most basic state, it accepts input, resolves the actions of entities, and renders the scene.
48
questions
262
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11answers
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When should I use a fixed or variable time step?
Should a game loop be based on fixed or variable time steps? Is one always superior, or does the right choice vary by game?
Variable time step
Physics updates are passed a "time elapsed since last ...
138
votes
3answers
90k views
What should a main game loop do?
Generally, what are the core things that one should do in the game loop, and what are some things that one shouldn't do in the game loop?
42
votes
5answers
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Should actors in a game be responsible for drawing themselves?
I am very new to game development, but not to programming.
I am (again) playing around with a Pong type game using JavaScript's canvas element.
I have created a <...
82
votes
5answers
17k views
What is the point of update independent rendering in a game loop?
There are dozens of articles, books and discussions out there on game loops. However, I pretty often come across something like this:
...
39
votes
3answers
22k views
When several classes need to access the same data, where should the data be declared?
I have a basic 2D tower defense game in C++.
Each map is a separate class which inherits from GameState. The map delegates the logic and drawing code to each object in the game and sets data such as ...
15
votes
2answers
11k views
Semi-fixed or Fully-fixed timestep?
I am making an iphone shmup and am trying to decide what type of game loop to use. I want to use either semi-fixed timestep or fully-fixed timestep.
With semi-fixed timestep I will make zero or more ...
29
votes
2answers
11k views
Is it safe to use Sleep() in game loop (on Windows)?
Is it safe to use Sleep() function on Windows in game loop (C++)? I want to have fixed frame rate.
19
votes
3answers
6k views
Design of a turn-based game where actions have side-effects
I am writing a computer version of the game Dominion. It is a turn-based card game where action cards, treasure cards, and victory point cards are accumulated into a player's personal deck. I have the ...
19
votes
2answers
6k views
Where should collision detection logic be placed?
I am developing a small 2D game engine. The characters have a paint method which currently does the following:
Calculate the new position of the character as per its speed, etc.
Update the collision ...
31
votes
2answers
33k views
A good way to build a game loop in OpenGL
I'm currently beginning to learn OpenGL at school, and I've started making a simple game the other day (on my own, not for school). I'm using freeglut, and am building it in C, so for my game loop I ...
6
votes
1answer
3k views
How to chain actions/animations together and delay their execution?
I'm trying to build a simple game with a number of screens - 'TitleScreen', 'LoadingScreen', 'PlayScreen', 'HighScoreScreen' - each of which has it's own draw & update logic methods, sprites, ...
3
votes
2answers
1k views
Using an interpolated game loop (such as Gaffer's final game loop), will the frame be rendered out of sync?
A highly recommended game loop is one from an article called Fix Your Timestep. It presents a method to update using a semi-fixed time step with interpolated rendering.
The problem with this is that, ...
35
votes
3answers
30k views
What is the standard C# / Windows Forms game loop?
When writing a game in C# that uses plain-old Windows Forms and some graphics API wrapper like SlimDX or OpenTK, how should the main game loop be structured?
A canonical Windows Forms application has ...
13
votes
3answers
2k views
Game loop, how to check for conditions once, do something, then not do it again
For example, I have a Game class and it keeps an int that tracks the player's lives. I have a conditional
...
19
votes
1answer
4k views
Behavior Trees :: Actions That Take Longer Than One Tick
From what I understand on Behavior Trees, each Behavior should be a short goal oriented Action that could be done in a few iterations.
So for example, below is an image of a Behavior Tree:
Now let ...
16
votes
9answers
4k views
How do I best remove an entity from my game loop when it is dead?
Ok so I have a big list of all my entities which I loop through and update. In AS3 I can store this as an Array (dynamic length, untyped), a Vector (typed) or a linked list (not native). At the moment ...
10
votes
2answers
20k views
What's the difference between Update and FixedUpdate in Unity, and should I bother?
I was told to use Update() for graphics and FixedUpdate() for physics, but sometimes my inputs won't register when I use ...
4
votes
1answer
5k views
Implement an upper FPS limit in the gameloop
I implemented my game-loop as described in deWiTTER's article, using the last approach with an unlimited FPS and a constant game-speed.
My problem is, that the unlimited FPS cranks up my CPU usage to ...
10
votes
2answers
2k views
Replay system: record inputs or events?
I read this: How to design a replay system But it don't really answer my question.
My game is built with the client "view" of the game as a separate program from the server "model" and "controller". (...
1
vote
2answers
696 views
Updating entities in response to collisions - should this be in the collision-detection class or in the entity-updater class?
In a game I'm working on, there's a class responsible for collision detection. It's method detectCollisions(List<Entity> entities) is called from the main ...
0
votes
2answers
752 views
How to detect collision between two directed object?
I'm currently writing a game which is like Battle City game. But right now I'm facing a trouble involved to checking collision between two objects. This is the code that I wrote:
...
14
votes
2answers
4k views
“Optimal” game loop for 2D side-scroller
Is it possible to describe an "optimal" (in terms of performance) layout for a 2D side-scroller's game loop? In this context the "game loop" takes user input, updates the states of game objects and ...
16
votes
3answers
7k views
Finite state machine in C++
So, I've read a lot about using FSMs to do game state management, things like what an FSM is, and using a stack or set of states for building one. I've gone through all that. But I'm stuck at writing ...
20
votes
5answers
2k views
Game actions that take multiple frames to complete
I've never really done much game programming before, pretty straightforward question.
Imagine I'm building a Tetris game, with the main loop looking something like this.
...
8
votes
2answers
5k views
Multi threaded game - updating, rendering, and how to split them
From the StackOverflow post (it was recommended I move this):
So, I'm working on a game engine, and I've made pretty good progress. However, my engine is single-threaded, and the advantages of ...
8
votes
1answer
754 views
How can City-sim simulate hundreds of characters?
My games usually start lagging quite easily when there are a couple hundred of boxes representing possible characters. While games like SimCity or even Anno have hundreds of characters.
I realized ...
8
votes
1answer
6k views
CPU usage, game loop and sleep()
I've read about this topic on numerous discussion sites, but I can't seem to find a clear definitive (up-to-date) answer, and hopefully this will me some more insight:
I've read the excellent game ...
7
votes
3answers
2k views
What are “frame rate” and “fps?”
Can someone give me a detailed
explanation about frame rate and fps concepts?
4
votes
1answer
5k views
Java Game Loop Efficiency
I'm quite new to java.
I was watching 2 video tutorials on how to make java game and read a couple articles about game loop. However, I'm still confused about how game loop actually works.
The ...
7
votes
2answers
2k views
Correct order of operations in a platformer game loop
I've run into an issue with my Mega Man engine, and the structure of my game loop is making it very difficult to fix. With Rush Jet, or any falling platform, Mega Man needs to stay attached to the ...
10
votes
2answers
6k views
Java 2D game programming: Different approaches to make a game loop
I am new to Java game programming, but the more I read the more I'm confused, because I've seen several different approaches to make a game loop:
1. The standard approach, that uses the Timer class (...
8
votes
2answers
5k views
Server side game loop
Many java games use thread.sleep() to controll fps. Since the server does not display graphics, should the server game loop keep running just calculating delta time? Like this example:
...
0
votes
3answers
5k views
C++ GameState management [closed]
I have been attempting to make a game engine in C++ and have come across the dilemma of game state management. I have done a lot of research and found numerous ways of accomplishing from game engine ...
4
votes
2answers
984 views
Fixed timestep with interpolation & rounding draw positions: jerky animation when the character is not moving
I've implemented a deterministic, fixed timestep system from here:
http://gafferongames.com/game-physics/fix-your-timestep/
Everything works fine, output is the same with each step but there's one ...
3
votes
3answers
1k views
How precise should timers in update loops be?
What is the suggestion of "enough precision" in a timer for a fixed game update loop?
Currently I'm testing with this code, but it sometimes misses 1-2 updates @ 50hz. While at 30hz it seems to work ...
3
votes
1answer
1k views
does order of updates and renders matter?
I know in a game loop there needs to be an order like physics should update before rendering. So, I have created two separate functions: update and render and the game loops like below:
...
2
votes
1answer
1k views
javascript game loop and game update design
There is a main game loop in my program, which calls game update every frame. However, to make better animation and better control, there is a need to implement a function like ...
4
votes
3answers
1k views
Best practices on separating Update and Draw on game loop
I've been working on my first HTML5 prototype and I found a good model that uses the regular Update and Draw loop we see in game dev. My question is, where does one end and the other begins?
The ...
3
votes
2answers
6k views
Turn-based Strategy Loop
I'm working on a strategy game. It's turn-based and card-based (think Dominion-style), done in a client, with eventual AI in the works. I've already implemented almost all of the game logic (methods ...
2
votes
5answers
5k views
How to make the game run at 60 FPS in Irrlicht?
I want my game run at 60 fps, but I don't know where to start, I have the simple loop:
while(device->run()){
How do I lock the frame rate to 60 FPS?
2
votes
4answers
2k views
Android Game-Loop (rendering & logic removed, but still 'skipping frames')
Overview
Guys really hoping for some help here. My game loop is based on code from Fix Your Timestep!.
I've read the article more than a few times, but I can't quite work out what exactly is ...
2
votes
1answer
3k views
Should game logic update per second or per frame?
I'm trying to wrap my head around how and when to update an entities position.
My game loop updates logic at 25 FPS and renders at 50-60 (Depending on the computer hardware).
So lets say I'm moving ...
2
votes
1answer
394 views
Client and server loops don't match up
I'm trying to build a small networked game using WebGL and NodeJS. I have a basic client and server setup and I'm at the point where I'm trying to implement dead reckoning to simulate what happens on ...
2
votes
2answers
525 views
Questions About Game Loops
I've been reading up how to lay out a game loop that'll work optimally in both great and not so great conditions but I think I've confused a few techniques together... so I have some questions...
...
1
vote
2answers
374 views
How can I fix my velocity damping to work with any delta/frame time?
I am decreasing my velocity by 50% every second using a guide I found online. I am using the code here and it gives the right result but only for very small values for dt:
...
1
vote
2answers
85 views
Updating bots/AI behavior after a fixed elapsed timestamp in game loop?
I am developing a HTML5 game in javascript. Now I have created a few bots and they should be able to change their orientation after a few seconds/a fixed timestamp in the game loop.
Suppose my game ...
0
votes
1answer
2k views
In some games, we just let the main() loop be the Player object or Table object?
I was thinking that let's say if there is a game of Blackjack or MasterMind, then we should have a class called Dealer or ...
-3
votes
1answer
3k views
What can be the cause of sudden lag spikes in my Android game?
My Android game has sudden lag spikes sometimes. I know this is due to something going wrong. My phone has a 1GHz processor so there shouldn't be a problem. Basically I use the ...
