# Tagged Questions

2D refers to two dimensional space where coordinates are represented with X and Y values.

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### Algorithm for procedureral 2D map with connected paths

Problem to solve: Generate a random 2D dungeon map for a tile-based game where all rooms are connected. I am looking for better solutions than what I currently have. My current solution is that I ...
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### Vehicle physics with skid

How would I go about creating vehicle physics for a car that can loose traction? I want it to seem like the driver has a flat foot, so when you press the gas, they cars driving (rear) wheels loose ...
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### Curved movement between two points

What is a good technique to enable an object to move between to points in a nice curved motion? The end position could also be in motion, such as the trajectory of a homing missile.
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### How can I generate random lakes and rivers in my game?

I have a 2D block building game and am trying to make randomly generated lakes and rivers. I have looked into the Perlin noise algorithm, but, I couldn't get it to generate random and nice results. I ...
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### 2D Level design/editing/saving questions [closed]

I thought about making a simple 2D Sidescroller game like SuperMario. Then i wondered about how to save, load or create the levels for the game. The first thing i thought of was drawing a simple ...
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### How to deal with corner collisions in 2D?

I'm writing a top down 2d XNA game. Since its my first I'm trying to write the physics and collision stuff myself to learn it. Whenever my player sprite character attempts to move into a position ...
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### Angle of Reflection

I have this "Breakeout style" game. I have a cannon at the center, blocks around the cannon and pads around the blocks. This is how the game looks like: I've managed to get the collision per ...
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### Algorithm for randomly generating reachable platforms

I want to randomly generate reachable platforms on the fly for a 2D game. Right now, I am just creating platforms at random x,y positions. Only 4 platforms can exist at once, so once the 5th one is ...
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### How to calculate the vector of an interception?

Given are a twodimensional space, and 1 friendly spaceship standing still, one foe is moving NOT directly to the friendly ship with known actual position, speed and direction. The friendly ship wants ...
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### Sidescroller variable terrain heightmap for walking/collision

I've been fooling around with moving on sloped tiles in XNA and it is semi-working but not completely satisfactory. I also have been thinking that having sets of predetermined slopes might not give me ...
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### How to create a 2D region where sprites are automatically wrapped?

Edit Finally managed to get this to work, after two separate questions! Here's a video demonstration: http://www.youtube.com/watch?v=nZ7e0jegvs0 Will write an article about it later when I have a ...
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### In a 2D top-down game, how can I create projectiles that have a height?

A 2D game called Deer Hunter has projectiles like this: Are the projectiles 2D or 3D models? How could I implement something similar?
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### Collision resolution in case of collision with multiple objects

I have static objects and movable objects. The collisions are detected using the separating-axis-theorem. For example, in this situation I have two static objects (in red): and a movable object ...
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### Appropriate level representation / data stucture for a 2D platfrom game?

I'm about to program a copy of Mario in Java. I'm thinking on 2 representations/data structures for the levels but I'm not sure which one should I choose: A 2D integer array. A quadtree to divide ...
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### Scrolling background loop

I'm trying to scroll my background forever and so I'm using the background image twice. When the first one goes off screen, it should relocate to the end of the second one. However, there seems to be ...
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### 2D Platformer Collision Handling

I am trying to create a 2D platformer (Mario-type) game and I am some having some issues with handling collisions properly. I am writing this game in C++, using SDL for input, image loading, font ...
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### Friction in 2D game

I'm developing a 2D platformer, although this question could probably apply to just about any 2D type physics; What is the equation for friction? I have sort of a hacky type of friction set up in my ...
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### Can you help me find resources for developing a top-down 2D game in Java? [closed]

I just started reading about games, and I'm going to develop a game where a person is moving around on a 2D map. My preferred language is Java. Is that suitable to develop games? I'm going to ...
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### How do I make a 2D character aim their gun toward the mouse?

Heli Attack is a perfect example of the shooting mechanic I'd like. The character aims perpetually toward the mouse. What's going on here? From what I've read so far, you could separate the arm and ...
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### Triangle - Rectangle Intersection in 2D

I had previously asked this for 3D but now I changed my strategy and would like to do the intersection in 2D. The Rectangle is axis aligned and will always be in a fixed position, and has a constant ...
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### Recommended 2D Game Engine for prototyping [closed]

What high-level game engine would you recommend to develop a 2D game prototype on windows? (or mac/linux if you wish) The kind of things I mean by "high-level" includes (but is definitely not limited ...
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### What to consider when deciding on 2D vs 3D for a game? [closed]

How much "harder" is 3D than 2D in terms of: Amount/complexity of the code Level of math skills required Time involved in making art assets Original title: How hard is 3D game development versus ...
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### Cross Platform 2D Graphics Engines [closed]

I'm looking for a 2D graphics engine that would allow me to release to Windows, Mac and the iPhone, much the way Unity does for 3D. Is there a good engine that does this and is specific to 2D?
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### How can I identify feature regions in a procedurally generated world?

I'm building an Island. I use the classical heightmap solution : with a hill-building function, avoiding the corners of the map, I make altitude. Then, perlin noise give me some climatic variables to ...
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### Is there a good way to get pixel-perfect collision detection in XNA?

Is there a well-known way (or perhaps reusable bit of code) for pixel-perfect collision detection in XNA? I assume this would also use polygons (boxes/triangles/circles) for a first-pass, quick-test ...
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### How do I make a character capable of walking on walls?

I am trying to get a character to move like a spider: Given a rising slope which a ball would normally not be able to roll up, the spider would slowly crawl up. Similarly, given a mid-air rectangular ...
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### Rendering SVG art directly in XNA

Suppose I have a bunch of 2D art in some vectorized format such as SVG. Is there an easy-ish way to render that directly without having to implement a full SVG renderer myself? Of course I could ...
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### Creating an electricity/lighting/tesla coil effect in a 2D XNA game?

I'd like to create beams of electricity between two points very similar to this video: http://www.youtube.com/watch?v=eMJ8-56L3Lc. The effect is so dynamic, with varying lengths and pseudo-random ...
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### Terrain Generation for Tile-Based 2D Platformer

I'm currently working on a tile-based 2D platformer similar to Terraria in some ways, although I'm having difficulty with the terrain generation. I have some basics done, although they do not come out ...
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### Quick 2D sight area calculation algorithm?

I have a matrix of tiles, on some of that tiles there are objects. I want to calculate which tiles are visible to player, and which are not, and I need to do it quite efficiently (so it would compute ...
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### Procedural Generation of Infinite Level

What are some good approaches to procedurally generating an infinite 2d level? The level could be constrained in either dimension but not necessarily. The approach that makes most sense to me so far ...
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### What's the most efficient way to find the intersection point of a missile and a bitmap terrain?

Following up on my earlier question about finding the slope of a 2D bitmap terrain I now need to know the best way of finding the point on the 2D terrain that the missile hit. Obviously, I can see if ...
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### Mega Man-style screen scrolling design

The NES classic Mega Man series uses a very specific scrolling technique that I'm having a hard time wrapping my head around implementing. Essentially, the level is divided into "screens" which are ...
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### Best way to store game-wide variables

I have an options screen for things like difficulty, resolution, full-screen, etc., but I'm struggling to find the "best" way to store/obtain these variables at run-time. Currently, I've implemented ...
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### Map with 20 million tiles makes game run out of memory, how do I avoid it?

While loading extra huge maps, the loading method throws out of memory exception where a new instance of map tile is created. I'd like to have whole map processed at least on server app (and on client ...
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### C# Perlin noise - generating “endless” terrain chunks?

I'm currently writing a little side scroller in C#, to both learn C# and have fun. Right now I have a simple random number generator generating the world but it isn't exactly all that great - so with ...
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### What is a good book to start programming a 2D C++ game?

I have a degree in Computer Science and while I was in college, I created a simple 2D game in Game Maker. I would like to recreate this game in C++ as a start to learning how to create games in C++. ...
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### The Physics behind 2D Platformer Games? [closed]

Is there any good book or tutorial that explains the physics behind creating a 2D Platformer game? Such as tile rendering, tile map reading, collision detection, camera movement etc.?
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### 2D Top down view maps

I was wondering how this works. Do you load the complete map when the game starts up, or do you load parts of the map at runtime? And how would you save the maps? Would it be in XML or some binary ...
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### Pathfinding with 2D, non-grid based movement over uniform terrain

I'm looking for the best solution to pathfinding in my game. The map is ultimately grid-based, but entities are positioned using floats, and can move in any direction to any point on the map. The '...
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### Slopes in 2D Platformer

I'm dealing with Slopes in a 2D platformer game I'm developing in XNA Game Studio. I was really tired of trying without success, until I found this post: 45° Slopes in a Tile based 2D platformer, ...
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### 2D Platformer Collisions

I've basically asked this question before, and I know it's been asked probably a billion times, but I still can't seem to do it. All I want to know is how I should go about doing basic 4-way, ...
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### How are “2.5D” art assets created?

By "2.5D" I mean the art style in games such as Roller Coaster Tycoon, Age of Empires 2 or Fallout 1 and 2: Everything in the games appears to be created with a "pixel art"-like tool. Am I correct? ...
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### How do you handle uneven tiles while rendering a tile map?

Here is what I want to do with my tile map that I am unsure of. As you can see the top walls are way larger then the bottom and side ones (this is also an issue with my corners which are odd shapes [...
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### How do I implement deceleration?

I say "deceleration" because I'm not using acceleration at the moment; what I mean is moving the velocity back towards zero, eventually stopping. I'm new to vectors and not so great with physics and ...
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### Why does Unity in 2d mode employ scaling and the default othographic size the way it does?

I previously used SFML, XNA, Monogame, etc. to create 2d games, where if I display a 100px sprite on the screen, it will take up 100px. If I use 128px tiles to create a background, the first tile will ...
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### 2D lighting theory: day-and-night cycle, spot lights at night

I am writing a rogue-like 'zombie' management game. The game map will be similar to Prison Architect. A top-down 50 X 50 grid. I want to implemented a day night cycle and during the night I would ...
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### Efficient path-finding on 2D tile-based multilevel map

It's a question I've been thinking about for some time... How do you effiently find a path on a 2D tile-based multilevel map? The map I use, for example, is 2048 on 2048 tiles wide. It has 14 levels ...