Physics Based Level Design

The physics-based level is a breath of fresh air for the Breakout genre. These types of levels were made popular (if not introduced) by Nurium Games’ BreakQuest. In these levels blocks (or other objects) tend to persist when hit by the ball, knocking into other objects to create a complex physics-based interaction. Batting objects around frequently becomes the primary focus of a level, creating barely controlled chaos. This makes BreakQuest levels very dynamic. The great interaction between onscreen objects also makes the levels feel more cohesive and often quite humorous. Jiggling. Swinging. Scrunching. These are words you would never have expected to associate with Breakout-style game play.

Here is a short Q/A with the developer of BreakQuest, Fèlix Casablancas.

Why did you decide to make a physics-based breakout game?

Fèlix Casablancas: I had some game ideas but finally decided on ‘Breakout with physics’ as I wanted to do something original but accessible for a one-man team. There are lots of Breakout-style games, another one would not be a great thing. But adding physics to the classic game mechanics opens up a whole new dimension for level design. I also wanted a ball that moved in a realistic fashion.

What led you to decide traditional block-based levels wouldn’t be the focus of your game?

FC: As I said, there are already many Breakout games and block-based levels don’t offer enough flexibility to be able to create something really different. In fact, if I hadn’t come with the physics idea I wouldn't have done a Breakout. With block-based levels, moving bricks that (for example) hang one-from-another connected with springs is just unthinkable. With a physics engine this is something relatively easy.

Was there any special reasoning behind particular objects/shapes you chose to populate your levels with or particular types of motion you chose to highlight?

FC: Well every level had his reasoning. Shapes are quite varied, from the classical rectangular brick, circles, triangles, stars and others. For example, the asteroids level where bricks break in smaller irregular chunks when hit by the ball, also bricks that look like aliens, little monsters or whatever. About the motions…again variety is what I was looking for. Some things move in a linear predictable fashion, others collide and interact amongst themselves and the scenery via springs and other constraints, controlled purely by the physics engine or helped with some hard coded algorithm – with or without gravity, with different levels of friction, torque and mass, just rotating in response to ball hits, or even vanishing to appear somewhere else.

When building levels, how were you able to predict the interactions between objects, or was the level design process mainly trial and error?

FC: Well in some levels the interactions were quite predictable but others required serious adjusting from the original designs. Trial and error has been important but you always need to start with the basic idea before experimenting with tweaks.

What type of visual impact were you trying to achieve with your level designs?

FC: I was trying to get a retro look but with vibrant colors and a bit of pixel art but with some modern designs and special particle effects. Kind of updated retro.

Since your game levels are so widely varied, what steps did you take to ensure that players were able to understand level objectives?

FC: Well, most levels consist of directing the ball to whatever you see and check if breaks. Others require some explanation and a small ‘tip’ window has been enough to clarify. I think that players may be a bit shocked at first but as they advance in the game they get a sense of what has to be done in each particular level.

What’s the most important piece of advice you’d give to a developer looking to build a Breakout-style game with complex physics?

FC: If you’re going to use a physics engine (as I did) before choosing one you have to do some research. There are a few ways to implement a physics simulator – different algorithms will have problems in different situations. So depending on your game mechanics one may better than the others. Also you have to understand what’s going on under the hood because the math may become unstable in some configurations and you need to understand why the engine blows up to find a suitable workaround.

What plans do you have for BreakQuest and Nurium Games in the future?

FC: About BreakQuest: there is a mobile version in the making. I hope it will be ready in a few months. Also a company is developing a Nintendo DS version but this is more a project than a reality at the moment. There are also talks about porting it to one of the big consoles, but just talks at the moment. About Nurium Games: I'm working on a puzzle game, no physics this time. But the mechanic is quite original and hope it will do well. I don’t really know when it will be finished as I have too many projects right now!