Why would you want to use physics to make a video game? How would you benefit from all the extra work needed to add physics to your game engine? Does it really work? What are the pros and cons?
Kraken Empire is composed by only 2 members. We wanted to make games no one had played before. A new and hopefully better gameplay in some way. We are best at programming, so our game would be based on programming and procedural generation. We needed to avoid complex modelling and animations as no one would have enough time for them. A game with vehicles in a space environment was something we could afford. We wouldn’t make the next AAA space game, but we could add something new to space games: real physics.
The first improvement to be done in a space game using physics are spaceship controls. Using physics, ships can be moved however we want with all the smoothness the physic engine provides. Of course the engine won’t do all the work for us, we will need to apply discretization and numerical integration. The forces to apply are integrated along time and applied through the physical engine. We use objects that we call propellers that apply forces to the object they are attached to, according to their own power curve and integrate the values along time to be used by the physical engine. The same is used for enemies and friction when needed.
At the beginning we didn’t know how it would work when finished, but the results are even better than expected. The smoothness we have reached is something we haven’t seen before and it is even more evident if you play other space games after playing KROMAIA. Our universe feels completely coherent because every object is physically modelled. As a result the game is really immersive as we were expecting from a game without interface that takes place in an extremely solid and coherent world.
Using physics is the only way to implement complex physic interactions. Making a black hole is not difficult by itself, but when you plan a battle between different enemies firing hundreds of projectiles and colliding with asteroids while all of them are attracted by the black hole… you can’t just implement every interaction by hand and hope the best. You need physics to make it believable.
Of course, it is not the way to go for everyone and every game nowadays. We wouldn’t recommend it for indies either, unless you want to make a new control as we have done. But physics should be used seriously in every game sooner or later, since it is the only way to make coherent worlds and responsive controls as we see them.