Game-facing refs

Game-facing identity handles. The only way game code (Zig / Kawa) references things.

URI forms (full rules: Assets and Shinra — Asset URIs and packs):

There is no pack-search form. Seal enforces one path → one pack.

Path identity (engine internals): Shinra pipeline events may still emit cooked suffixes. Compare stems with asset_kind.stemsEqual / asset_deps.stemsEqual (not bare string/pathsEqual). Scenes use scene_ref.stemOf / withAuthoringJson / withCooked for store and editor disk loads.

Shaders are AssetKind.shader but identity is a package id (gbuffer_wacky, _engine/gbuffer), not a file stem. Platform expand lives in graphics/material/shader_artifact.zig (Metal one .metallib; D3D12 _vs_/_ps_/_cs_.cso). Materials still set shader.package; runtime acquires expanded store paths only for the synchronous native copy/compile and then releases them. Session launch binds AssetStore; device-init must follow launch.

Not refs (plain names): archetype, input action, message name, physics preset, audio bus.

Engine-internal native atoms (AudioHandle, RenderHandle, PhysicsHandle in src/hikari/src/native/handle.zig) back subsystem tables — games use AssetRef for cue paths and VoiceHandle for live voices.

Dead / invalid ActorRef → host no-ops (never crash). Bad AssetRef / ContentRef → validate fail / soft no-op.

Implementation: sdk/src/asset_ref.zig, content_ref.zig, scene_ref.zig, prefab_ref.zig, actor_ref.zig. Kind + suffix table: sdk/src/asset_kind.zig (engine assets/asset_kind.zig re-exports). Host: host_api.zig + game_api/host_bind.zig.

Zig

const tex = hi.AssetRef.must(.texture, "asset://./textures/pbr_capsule_albedo");
const mat = hi.AssetRef.must(.material, "asset://./materials/default");
const cfg = hi.ContentRef.must("content://resources/ref_demo.json");

var parsed = try hi.json.parseRef(Config, allocator, cfg);
defer parsed.deinit();

const target = hi.world().find("target_zig");
if (!hi.world().isAlive(target)) return;

try hi.render().applyRender(target, .{
    .mesh = hi.AssetRef.must(.model, "asset://./models/cube"), // optional
    .material = mat,
    .albedo = tex,
    .notify_dirty = true,
    .release_primitive = true,
});

hi.world().send(target, ping);
hi.world().send(hi.ActorRef.invalid, ping); // no-op

hi.world().requestSceneLoad(hi.SceneRef.must("scenes/refs_demo"), .{});

• Literals: AssetRef.must(kind, uri) / ContentRef.must / SceneRef.must (comptime non-empty; scene/asset cooked suffixes are compile errors).
• Dynamic strings: tryFrom then host validate.
• EntityId is an alias of ActorRef.

Kawa

World.find(id) / Actors.find(id)        → ActorRef | nil
Actor.is_alive / Actors.is_alive / send → safe on dead
Actors.has / get_number / set_number    → component fields by name (dead → false/nil)
Content.read("content://…")            → string | nil   (content_dirs + AssetStore; no FS fallback)
Render.set_material(actor, mat [, alb])→ asset:// stems only (no .shin*)
Scene.set_skybox_texture("asset://…")  → asset:// stem (primary)
Scene.set_skybox_texture_secondary(…)  → asset:// stem (secondary)
Scene.set_skybox_blend(t)              → dual cubemap mix [0,1]
Scene.load("scenes/foo")               → SceneRef stem (not content://; not .json)

ActorRef is weak (holding a ref never keeps an actor alive). Prefer Actors.* / hi.actors for new find/send/field access; full guide: Actor communication.

Demo

scenes/refs_demo (Browse scenes → Tutorials → References; on disk refs_demo.json / .shinscene):

Data: resources/ref_demo.json, resources/ref_demo_note.txt.