Take the 2-minute tour ×
Game Development Stack Exchange is a question and answer site for professional and independent game developers. It's 100% free, no registration required.

By "2.5D" I mean the art style in games such as Roller Coaster Tycoon, Age of Empires 2 or Fallout 1 and 2:

Some in-game art from Age of Empires 2

Everything in the games appears to be created with a "pixel art"-like tool. Am I correct?

How are the moving characters are created though? Take AoE2: For much of my childhood I was convinced that the soldiers, villagers and other characters were 3D!

Could someone explain:

  1. What dimensionality are the characters?
  2. What sort of software package could I use to create them?
share|improve this question
1  
Here's an example of RCT's graphics: chrissawyergames.com/feature3.htm –  CobaltHex Apr 11 '13 at 19:16

1 Answer 1

up vote 16 down vote accepted

Assets like these can be created in any 3D package.

They are imported into a game by pre-rendering the models at specified angles, using orthographic projection in the viewport. The pixel effect probably is a side-effect of rendering at a low resolution with little or no anti-aliasing. The spritesheets generated by these will be ordered in such a way that the application can mathematically compute which frames apply to which angles and animation frames.

In Age of Empires 2, you can easily tell that the structures are pre-rendered 3D assets, especially by how they have such a low frame rate of animation. The reason for this is simply disk and memory consumption. Animating large images like those at a high frame rate will bloat the asset sizes tremendously, on disk and in memory. The smaller sprites, e.g. the villagers, can have much higher rates of animation, as they are comparatively small and less intensive. This is also why the units in the game have only 8 directions of rotation, as accommodating all potential rotations and animation frames will, again, bloat disk and memory consumption (not to mention rendering time too).

There are some games however that do use a 3D method for rendering certain objects. Take C&C Tiberian Sun and C&C Red Alert 2 for example. The infantry and structures use pre-rendered sprites, like AOE2. However the vehicles use a 3D rendering technique called "Voxels", which are essentially 3D bitmaps that are rendered in real-time, which is why they have such a large variety of angles and positions, whilst still having that "2.5d" look.

Somewhat Unrelated: Also I believe that 2.5D normally refers to 3D rendered games that use 2D gameplay mechanics. I may be wrong in this case, but that is how I refer to it. :)

share|improve this answer
2  
The usage of the term "2.5D" is gradually shifting. I first heard it used to refer to games like Doom where the graphics looked 3D but were actually a first-person rendering of a 2D heightmap. –  Gregory Avery-Weir Apr 17 '12 at 17:39
4  
2.5D means a whole bunch of different things in different contexts. There's no official definition of the term; basically anything where there's a combination of 2D and 3D in terms of gameplay, visuals, etc. is totally fair to call "2.5D" –  fluffy Apr 17 '12 at 18:51
    
Thanks for the Answer Jason, and welcome to GDSE! –  Byte56 Apr 17 '12 at 21:25
    
I interprete 2.5d as the exact opposite: a game with a 2d game engine which uses 3d mechanics. This is usually visualized with an isometric or dimetric perspective. –  Philipp Apr 12 '13 at 15:05

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.