RaGE

Oct 2003 – May 2004 · age 21–22

What it was

The character half of a two-person graduate course project: a "virtual reality engine" for a shooter fought on the inside of a hollow world, with a classmate building the spherical terrain and Jeff building the actors. The engine wrapped SDL around OpenSceneGraph, with ODE for physics, SOLID for collision, and Jeff's own GUI library loading screens from script. A player walked the inside of a sphere and cross-faded from running into jumping without a pop. The real star was a benchmark: skin the character on the CPU at four moments, hand the GPU a cubic Bézier through those poses, and let an ARB vertex program produce the motion in between. "The Army Test" kept adding characters while plotting frame rate and recording itself to video. Six small tools prepared the meshes. The game itself was never started.

Wins, for the age

• At twenty-one, walked a player around the inside of a sphere with its own orthonormal basis and gravity toward the centre, three years before Super Mario Galaxy (2007) made spherical walking famous. A toy demo, and spherical worlds already existed, but the maths held.
• Split skinning between a slow CPU pass and a smooth GPU curve, a genuine twist on the GPU keyframe tweening of the day (2000).
• Remapped bones into per-primitive palettes of twenty matrices, with an offline tool to make every mesh fit, on hardware a modern phone would pity.
• Benchmarked with a video that recorded its own evidence. Few young mammals think to make the proof film itself.

What it taught

• Write the proposal first. It turned a pile of demos into a plan.
• Integrate other people's libraries: SDL, OpenSceneGraph, ODE and SOLID in one loop with a fixed timestep.
• Asset pipelines grow versions 2 through 12, and every assumption they enforce, like a twenty-bone cap, must also be checked at runtime.
• Build to a benchmark. The CPU and GPU split, measured, is the shape of every later performance argument.

Genealogy

Ancestors: GGPlus: the scene-graph GUI library that loaded RaGE's screens. Lib Quest: game logic dispatched as events to separate handlers. Zenerd: skinned meshes with four bone weights per vertex. Zsl: the personal engine foundation of math and collision. Descendants: Cauldron v1: keyframe animation and GPU skinning grew into a real engine. Cauldron v2 Epic: a skinned character walking a world under physics.

Epitaph

Here lies RaGE, which taught a GPU to draw the curve between four poses and never got around to the war at the centre of the earth.