Development of Spore - Procedural Generation

Procedural Generation

Spore extensively uses procedural generation, rather than individual objects. Wright mentioned in an interview given at E3 2006 that the information necessary to generate an entire creature would be only a couple of kilobytes, according to Wright, who presented the following analogy: "think of it as sharing the DNA template of a creature while the game, like a womb, builds the 'phenotypes' of the animal, which represent a few megabytes of texturing, animation, etc."

In Spore, all creature animations are made on the fly. "The game automatically knows how to animate your creature based on how you put it together. For example, if you give your creature four equine legs, you can logically expect it to gallop around like a horse."

In Wright's first public demonstration of Spore, he created a tripedal reptilian creature in the creature editor (this creature was dubbed the Willosaur by fans, after Wright, and became one of the mascots for the game, appearing prominently in the game's first trailer.). The game then determined how a lizard with three legs and a prehensile tail should walk. Other animations of the lizard including hunting, eating, swimming, dragging objects, mating, playing a drum and dancing, all of which were procedurally generated based on the model that the player created. Wright then revealed several pre-made creatures which moved realistically, despite their exotic design: large, insectile creatures with multiple heads and six legs, Tweety Bird the SUV: a walking bird whose massive head caused it to tilt while turning, and a dog-like creature with a set of unusually branching limbs. Wright also humorously demonstrated a creature that looked like a Care Bear (claiming it would be a vicious carnivore), indicating that players could create animals similar to those found in nature or popular culture. This also applied to vehicles such as space ships, as demonstrated in the Gadgetoff video, in which Wright was seen piloting a UFO similar to the USS Enterprise.

Chris Hecker, who currently works on Spore (including its early prototypes), gave a presentation at GDC 2005 and Futureplay entitled "Why you should have paid attention in multivariable calculus", in which he describes the mathematics of an implicit surface and various methods to apply texture projections to such surfaces. Sean O'Neil worked as a consultant for Maxis "to assist with R&D involving dynamic generation and rendering of a fractal-based world". He maintains a website with a demonstration of procedural planet generation and a simulation of dynamic atmospheric scattering.

Wright noted that he hired a handful of demoscene programmers and artists because of their familiarity with procedural generation. An example of software they used was ParticleMan, which simulated gravitational attraction between particles in a cloud, which would be incorporated into the space phase. It helped orchestrate such gravitational dynamics as orbits, nebula formation, star formation and particle streams from sources like pulsars and black holes. ParticleMan was developed internally at Maxis by Jason Shankel and uses the GLUT OpenGL app kit developed by Mark Kilgard and the GLUT-based GLUI UI library developed by Paul Rademacher.

The official site allows users to sample a number of Spore prototypes, which include ParticleMan, SPUG, City Maze, and other software, all under 1000KB in size, save the 20MB Space, and the 45mb Gonzago.