Schema — HolonPrint (render-method contract) · schema-holonprint

Owner directive (2026-07-10), canonical. "Make it possible to add runs on each Holon, Gaussian splatting is one, using 3d models is another, the Holonprint (how it is rendered) shoul dbe able to even use, genmodels, for videos, 3D, pixelstreaming, AR, Sensors, etc. For now, generate with the Holonprint Loop with gaussian splatting…" [src: wiki/development/prompts-archive/by-topic/knowledge-management-and-concept-modeling.md:496]

Content

The render-method contract of a holon: how a knowledge/world holon is materialized on a surface. One holon may carry several HolonPrints (one per method); the engine picks by capability and budget. gaussian-splatting is the method in production ("For now, generate with the Holonprint Loop with gaussian splatting" — the @hos/engine package describes itself as a "Gaussian-splat scroll-film HolonPrint renderer" [src: HOS-Instance/packages/engine/package.json:5]). The budget object generalizes the engine's manifest fields (bytes/count per quality tier + world AABB) [src: HOS-Instance/packages/engine/src/engine/contracts.ts:17].

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "hos://schemas/holonprint.json",
  "title": "HolonPrint — how a holon is rendered",
  "type": "object",
  "required": ["id", "method", "asset", "budget"],
  "properties": {
    "id": { "type": "string", "pattern": "^[a-z0-9][a-z0-9-]*$" },
    "method": {
      "enum": ["gaussian-splatting", "genmodel", "mesh3d", "pixelstream", "ar", "sensors"],
      "description": "render pathway; owner enum verbatim (splats now, others by run)"
    },
    "asset": {
      "type": "string",
      "description": "asset reference — for gaussian-splatting: a SplatManifest entry id"
    },
    "budget": {
      "type": "object",
      "description": "hard resource ceilings the method must respect (bm-002 governs splats)",
      "properties": {
        "bytes": {
          "type": "object",
          "properties": {
            "desktop": { "type": "integer", "minimum": 0 },
            "mobile": { "type": "integer", "minimum": 0 }
          }
        },
        "count": {
          "type": "object",
          "description": "splat/vertex/frame count per tier",
          "properties": {
            "desktop": { "type": "integer", "minimum": 0 },
            "mobile": { "type": "integer", "minimum": 0 }
          }
        },
        "bounds": {
          "type": "array", "items": { "type": "number" },
          "minItems": 6, "maxItems": 6,
          "description": "world AABB [minX,minY,minZ,maxX,maxY,maxZ]"
        }
      }
    },
    "fallback": {
      "type": "string",
      "description": "id of another HolonPrint (lighter method) or a static asset used when capability/budget fails — e.g. CSS/image sibling when WebGL is absent"
    },
    "runs": {
      "type": "array", "items": { "type": "string" },
      "description": "run ids that (re)generate this print — 'add runs on each Holon'"
    }
  }
}

Invariants: a gaussian-splatting print's budget.count must fit inside the slice budget of bm-002-splat-budget (engine ceilings: desktop 700k / mobile 300k [src: HOS-Instance/packages/engine/src/engine/contracts.ts:149]); every print SHOULD declare a fallback reachable without its method's capability (WebGL-absent path per cb-patterns-hosweb gotchas [src: HOS-Webdoc/web/src/lib/scroll/env.ts:14]); asset for splats must resolve in the SplatManifest.

Variants

Composition

• uses: holon (the thing printed) · gaussian-splatting · spark-renderer (method A runtime) · bm-002-splat-budget
• used-by: schema-genome-spatial-strand (slices[].holonprints) · pb-001-spatial-site-loop (steps 3–5 bake to this contract) · sc-001-kernel-cogni-genome (stage 4) · bp-001-spatial-site

See also

• holonprint — the concept card carrying both senses
• cb-spark — the production method's cookbook