2d vs 2.5d platformer...hmmmm?

I understand that there are 2 ways to build a 2d platformer. The first method consists of animating sprite textures - so everything really is 2 dimensional. The other method is to use 3d models instead of sprites - this is what I would call 2.5d. In either case, the camera is fixed on the z axis, but moves down the x and possibly up and down on the y.

I would like to know from those of you that have tried either way what are some pros/cons of each method. I'm leaning more to the 2.5d solution, but wanted to know if I was being shortsighted in my initial thoughts.


Thanks.

 

Given that `3D` is all the rage and seen by most as `progress`, there's been a big trend towards 2.5D even when it really adds practically nothing to the gameplay.. it's more for visual subtleties and perhaps helps if you want to do physics interactions in the game. Any 2D game should be able to transition to 2.5D or vice versa, for the most part. Developing 3D assets requires modelling abilities plus texturing/lighting etc, while flat sprites is more of a per-pixel artistry. The 3D is perhaps easier to pull off at a higher resolution because it stretches automatically, but high-res detailed sprites need a lot of work to fill in all those pixels. Some consider 2D `old school`, so it has a bit of a different image. I think most 2.5D games don't need to be three dimensional whatsoever, it's usually just a visual preference. Like the latest Sonic games are 2.5D (I think) but it doesn't have anything to do with the gameplay really.

 

Having built multiple platformers and having an asset store product which has many users doing both 2D and 2.5D platform games I'd say the benefit of 2.5D is you can retarget your animations and use cross fading and the like. Meaning you might save on art costs if you have complex animations or multiple characters. On the other hand if your animations are simple (for example 3-5 frame walk, jump, etc), then 2D will likely be less work/cost.

2D performance is pretty constant regardless of the quality/complexity of your art, whereas performance in 3D can vary (complex models and shaders vs low poly models and simple shaders).

But mostly the difference is aesthetic. Choose the style that fits your game, not the other way round.

 

3D gives the added benefits of dynamic lighting (i.e you don't necessarily have to have a day night version of your sprites), easier to work with from code, smaller file sizes(1 mesh+10 animations+1 256x256 texture is smaller than 10 sprite animations packed into an atlas), and at the very least for static objects, easier to render (1 mesh + 1 opaque vertexlit is cheaper than 1 sprite with transparency to fade the corners).

That said, you can get a lot of the style of sprites with a lot of the benefits of 3D by using rigged and animated planes with the sprites drawn onto them, ala Zombieville USA.