3D Games With 2D Sprites: Exploring the Possibilities

CEO & Founder at RetroStyle Games | Jan 27, 2023

Video game sprites are 2D images that represent game assets. It can be simple 2d game characters, enemies, projectiles, and props. A sprite is a bitmap that can be a static image or an animation integrated into a larger scene.

Typically, sprites are used in 2D games. But there are lots of titles with a combined approach that incorporate both 2D and 3D technologies in some way. One of them is using 2D sprites in a 3D world. Mixing these technologies gives an in-depth feeling and freedom of movement in a three-dimensional space, while still maintaining the simplicity and aesthetics of 2D graphics.

Benefits of Using 2D Sprites in 3D Games

Using 2D sprites in 3D games was a trend back in the 2000s. It gave the possibility to create 3D space when there was not enough hardware capacity to render real 3D game models. Even though modern hardware can now render realistic AAA graphics, mixed-approach games didn’t vanish.

The technology moved to the indie market, and mobile platforms, and is still used in AAA titles as well. In some cases, a mixed approach is the best option because of all the possibilities it gives you. Here’s why a mixed approach can be the best option for you:

1
Enhancing Game Performance
Detailed 3D models impact the performance of the game. Drawn and pre-rendered sprites solve this problem perfectly, allowing players to enjoy nice graphics that are cheap on hardware.
2
Faster development
We know that when it comes to game development, time is the essence. It’s hard for the artist to create a detailed 3D model. Whereas, making 2D sprites is a much faster way to fill in your game world. You can create 2D sprites either in-house or outsource 2D game sprites for even faster development. Besides, 2D sprites will add a special charming look to your game.
3
Reducing Memory Usage
Adding sprites individually for each object and animation frame, you will end up wasting resources for no reason. To reduce memory usage, you can store frames of animated sprite characters on a single sprite sheet. Moreover, you can pack together the sprites that are commonly used in the same scene.
4
Cost
Creating a three-dimensional, realistic game requires quite a large team of specialists. You can save on additional costs. Sprites are faster and easier to develop than 3D game modeling services.

Best Practices When Working with 2D Sprites in 3D Games

The way that sprites are typically used within 3D games is through rendering or imitating a rendered frame from certain perspectives. For sure, 3D games with 2D sprites have some limitations. Optimizing 3d models for games is essential, especially if you want them to look good and natural. To achieve the best results, we recommend you to use these techniques:

1
Use a fake perspective
First, create an isometric view using an orthographic camera. Then place sprites from a certain angle, making sure they always face toward the camera. This technique creates a subtle illusion of perspective, making sprites appear as 3D objects when they are plain images.
2
Skew character models
Skew character models towards the camera to make an illusion of perspective distortion.
3
snap to keyframes
Making sprites for games, snap to keyframes instead of complex animation. Restrict your sprite character’s movement to the main directions (top, bottom, left, right and sometimes diagonally).
4
Create sprite sheets
The number of available textures on a graphic card can be limited. Store animation frames on a single sprite sheet to access frames faster.
5
bake-in the lighting
Light the sprites in a certain way to make them consistent with the environment they are placed in. If you use pre-rendered 3D models, bake-in the lighting. Select the properties of the lighting in advance for the whole project, and then apply an orthographic global illumination completely equal to each model.
6
shadow blobs
Shadow casting would have to be done as generic programmatically generated shadow blobs.

Tools for Working with 2D Sprites in 3D Games

Developing a game with 2D sprites, there are lots of tools you can choose from depending on your preferences and budget. Since 2D sprites are simple images, you don’t need any special software to create them. You can use any type of paint software, like Photoshop and Gimp, to draw sprites. Or you can use exports from Flash, Illustrator, or any kind of animation software. If you want to use 3D models as sprites, choose a 3D software you’re familiar with and pre-render the final model.

Then it’s time to set up your sprites in a scene. If your game has an isometric perspective, choose the best engine for isometric games. To make Unity 2D sprites in a 3D environment, replace your tiles with cubes and texture one face, then swap out 2D hit colliders for cubes. For a player character, create a sphere collider. Render a character with a quad that’s always angled toward the camera. Don’t forget to place lights in the scene naturally or bake-in lights if you’re using 3D models.

Examples of Popular 3D Games with 2D Sprites

Many games in the 90s had 2D sprites in a 3D environment, with a fixed camera position towards the sprite. Mostly these sprites only had several images, like the front, left, right, and back. A player was moving in an area that looked like 3D or was a very limited 3D. These days some people may call these titles just one of the types of 2D games. It may sound quite interesting but we prefer to call it 2.5D games, although it’s a broad term that combines many concepts. However, 2.5D is still heavily in use today. Here are some examples of popular 3D games with 2D sprites.

Nintendo’s Paper Mario franchise is both aesthetically and mechanically centered around the interactions between flat and solid objects. The game has 3D polygon backgrounds and all the characters are flat sprites, always facing towards the camera. Paper-like characters have basically no thickness and flip as they spin around. The “paperness” of the world and characters is central to the game’s mechanics and gameplay. Mario folds himself into a paper airplane, moves sideways through tight spaces, and rolls himself into a tube.

The game is taking place in a 3D environment and uses sprites inserted into the world. The technology used in games like DOOM and Duke Nukem 3D is called billboarding. The term “billboarding” derives from the way game objects are presented – a “board” is a flat 2D game asset facing the camera and displaying the content. This also enables developers to use sprites rather than 3D models, as they make sure that the enemies will never be seen from above or below.

Don’t Starve is one of the best roguelikes on Steam. It is a hybrid approach game in a 3D environment with 2D art and billboard rendering. The sprites have 3D positions in the world and always face the camera. When the view angle changes, the sprite changes simultaneously to show the correct angle.

What Games Feature a Combination of 2D Sprites and 3D Environments?

2D sprites have been used since the beginning of the gaming era. There are several types of games that use a combination of sprites and 3D environments:

1
2.5D platformers
Modern 2D platformers with a side-view camera, in reality, may have a 3D environment. In games like Hollow Knight, surroundings are actually 2D sprites placed on a distance to each other. This trick creates an in-depth of space, while all characters and props remain two-dimensional.
2
Isometric games
Games with an isometric perspective are viewed from a certain static camera angle. To appear 3D, they tend to use rendered sprites placed in a 3D world. It can be either pre-rendered 3D models put on a spritesheet, or regular sprite drawings.
3
Games with polygon environments
These games use real 3D models for the environment, while characters appear to be two-dimensional.
4
AAA titles
Sprites are used in AAA games today to display grass and foliage, in the form of billboarding. Here, sprites will always face the camera to make the illusion of a 3D object. Sprites also can be placed for backgrounds in the large scene, where there is no need to render individual objects so far away. They can also be used in conjunction with cel-shading.

Conclusion

Sprites are used everywhere, and we don’t even realize it. The recent revival of isometric and pseudo-3D games is not just a source of nostalgia. It’s a great design decision with tangible visual and gameplay benefits. Adding an extra Z-axis to your game means it really has an extra gameplay aspect.

With the rapid growth of the mobile market, games with a mixed approach are gaining even more popularity. 3D games with 2D sprites embrace the best of both, being the greatest option when you want to have the beauty and volume of 3D graphics while still being cheap on hardware.

With a hybrid approach, game development is actually half faster than normal game design. Moreover, combining these two techniques, you can make even a low-budget game look gorgeous.

Benefits of Using 2D Sprites in 3D Games

Enhancing Game Performance

Faster development

Reducing Memory Usage

Cost

Best Practices When Working with 2D Sprites in 3D Games

Use a fake perspective

Skew character models

snap to keyframes

Create sprite sheets

bake-in the lighting

shadow blobs

Tools for Working with 2D Sprites in 3D Games

Examples of Popular 3D Games with 2D Sprites

What Games Feature a Combination of 2D Sprites and 3D Environments?

2.5D platformers

Isometric games

Games with polygon environments

AAA titles

Conclusion