Open motion_ribbons.pde in Processing 4.5.6 and press Run. Keep the full repository together so the sketch can load the shared files from ../p5f_sample/data/. No additional Processing library is required. For export, copy those three BVH files into this folder's data/ directory first.
The CPU caches five joint trajectories per dancer and samples a 3.2-second history into reusable PShape triangle strips. The strip width faces the current camera. The vertex shader transports position plus age/edge attributes, and the fragment shader adds thin bright edges and a restrained cyan, coral, or ivory sheen. The topology is generated on the CPU because standard Processing PShader provides vertex and fragment stages, not a geometry stage.
motion_ribbons.pde: playback, camera, drawing, keyboard controls.RibbonDancer.pde: pose cache, interpolation, triangle-strip vertices.data/ribbon.vert/data/ribbon.frag: the two shader stages.MotionData.pde: legacy BVH library adapter; recenters root X/Z for the side-by-side display.SketchRun.pde: capture and validation helper; the visual algorithm does not depend on test mode.
Change historySeconds, steps, or halfWidth in RibbonDancer.pde to change the trails. Change ink and the edge/sheen calculation to tune the material. At a motion loop boundary the trail starts fresh rather than connecting unrelated end/start poses.
Space pauses; drag orbits; R resets; H toggles labels; S saves a screenshot. Deterministic CLI captures are described in the root README.
Only the new sketch/shader code is covered by LICENSE-new-examples. The original BVH data and the parser JAR retain their existing copyright status.