APEX v3 uses existing, attributed 3D models, hand-built racing circuits, photographic sky lighting and authored sound samples. No text-to-image, text-to-3D or AI texture generation is used. These are community simulation assets, not assets from Forza Horizon or a claim of affiliation with any car maker or circuit operator.
Source: Kanagawa Z35 (Nissan 350Z), model by William Brun (original CC-BY), low-poly rebuild and Speed Dreams adaptation by W-E-C; texture and mesh improvements © 2012 Eckhard M. Jäger. The distributed adapted artwork is under the Free Art License 1.3.
Original source artwork · Original credits/license notice · Modified body GLB. Changes: AC3D → glTF, mesh regrouping by material, coordinate conversion and wheel/suspension rigging. Wheel geometry from Speed Dreams/TORCS shared objects, FAL: modified wheel GLB. Six-speed gearing, tire coefficients and power output are an independent APEX game tune, not measured Nissan specification data.
Both circuits and their shared textures are Free Art License artwork. Changes: AC3D → glTF; translation to a local origin; spatial mesh batching; SGI RGB → PNG image conversion; collision meshes and route centerlines extracted from the source triangles. Source geometry and texture artwork are retained. Converted artwork remains separately available under the Free Art License 1.3. GLB files reference the PNG files in the same directory; the asset manifest lists every file, source, attribution and SHA-256 hash.
AC3D reader source · conversion script · Speed Dreams license policy. Original and converted art can be obtained independently of the game. Trackside marks belong to their respective owners.
Sunflowers (Pure Sky) — photograph by Sergej Majboroda, sky edit by Jarod Guest, Poly Haven, CC0. Original 2K HDRI used for light and sky.
350Z engine sample comes with the vehicle source package, under its FAL notice. Tire skid sample: LukaCafuka, sampled/mixed by Overshot, CC0 source recording. Speed Dreams sound credits. Playback rate follows engine RPM; skid volume follows physical tire slip.
The controller is independent project code. Reference material: Project Chrono's tire models, Vehicle Physics Pro tire documentation, PhysX vehicles guide, Rapier scene queries. Combined-slip brush approximation, load-sensitive friction, slip relaxation, wheel angular dynamics, spring/damper contact suspension and limited-slip differential are implemented in TypeScript. The contact envelope uses three rays per wheel; it is not a full deformable tire model. No proprietary Forza code or parameters are used.
Car Concept — Eric Chadwick / Darmstadt Graphics Group, original Unity Fan, CC-BY-4.0. Kenney Starter Kit Racing — CC0. Spruit Sunrise — Greg Zaal / Poly Haven, CC0. Retained for source regression fixtures, not loaded in the v3 driving scene.
Three.js, Rapier, Vite, Vitest and Barlow retain their own licenses. See THIRD_PARTY.md in the source distribution.