add .agents/design/ — blog voice + rules for agents

gpu-skinned-herds.html

@@ -357,7 +357,7 @@ NORMAL = normalize((skin * vec4(NORMAL, 0.0)).xyz);</code></pre>
 <h2>What's driving it</h2>
 <p>In <a href="https://www.arikigame.com" style="color: var(--c-lime);">Ariki</a>, the sim tracks animal migration across a 12km archipelago. <code>AnimalHerdRenderer.cs</code> groups sim <code>ViewerState.animals</code> by type, feeds world positions and yaw rotations to <code>skinned_herd.gd</code> — the reusable per-type herd backend. The herd bakes the palette once at setup, then <code>set_positions()</code> updates transforms each sim tick. <code>set_clip_for_state()</code> switches the active clip block in the custom data when the sim FSM changes state. <code>set_speed_scale()</code> adjusts the per-instance playback rate to match ground speed — feet stay planted.</p>
 <p>The sim owns all behavior — 30 data-driven animals with per-animal senses, diet, combat stats, and FSM states (graze, drink, sleep, hunt, flee, scavenge, die). The client just renders. This is the same code in single-player and multiplayer — the sim is the host.</p>
-<p>Bird flocks use the same system. <code>BirdFlock.cs</code> runs boid flocking on top of <code>skinned_herd</code>, sharing the palette with synchronized phases (airborne flapping in unison is intentional). 25 bird species migrated from the Low Poly Bird Ultimate Pack, each a single draw call.</p>
+<p>Bird flocks use the same system. <code>BirdFlock.cs</code> runs boid flocking on top of <code>skinned_herd</code>, sharing the palette with synchronized phases (airborne flapping in unison is intentional). 25 bird species, each a single draw call.</p>
 <p>Per-instance custom data means a walking Boar, a running Boar, an idle Boar, and an attacking Boar all share the same baked palette — they just point at different rows. The renderer groups by type, not by state. One palette, one draw call, any number of states.</p>
 <h2>Two bugs we shipped and fixed</h2>
 <p>The module had data-plane doctests from day one — round-trip pose get/set, dirty tracking, size clamping, AABB, column-major layout. All green. Then we put it on screen and two things were wrong.</p>
@@ -369,7 +369,7 @@ NORMAL = normalize((skin * vec4(NORMAL, 0.0)).xyz);</code></pre>
 <p>Engine version: <strong>4.6.5.</strong></p>
 <p>No C# wrapper is generated — instantiate from GDScript via <code>ClassDB.instantiate()</code> and call the bound methods. The binding surface is small and stable. See <code>ariki-game/scenes/animals/skinned_herd.gd</code> for the reference backend.</p>
 <h2>The production pipeline</h2>
-<p>The <code>migrate_animals.py</code> tool converts polyperfect FBX packs to game-ready GLBs — imports, cleans hierarchy, rebuilds named NLA clips from frame ranges, strips duplicate meshes, bakes into the flat <code>assets/models/glbs/</code> directory. Each animal gets a catalog entry in <code>animals_catalog.json</code> with clip metadata, default state mapping, and an <code>animSpeedRef</code> for foot-sync.</p>
+<p>The <code>migrate_animals.py</code> tool converts source FBX files to game-ready GLBs — imports, cleans hierarchy, rebuilds named NLA clips from frame ranges, strips duplicate meshes, bakes into the flat <code>assets/models/glbs/</code> directory. Each animal gets a catalog entry in <code>animals_catalog.json</code> with clip metadata, default state mapping, and an <code>animSpeedRef</code> for foot-sync.</p>
 <p>At runtime, <code>AnimalHerdRenderer</code> spawns one <code>skinned_herd</code> per animal type. The herd bakes the palette from the catalog GLB's clips. <code>AnimalAnimationLogic</code> maps sim FSM states to clip keywords (attack → "attack"/"bite", flee → "run"/"gallop", wander → "walk"). The renderer lerps positions between sim ticks for smooth motion and writes per-instance custom data each frame. Zero per-frame CPU on the animation path.</p>
 <h2>Where we stand vs the industry</h2>
 <p>The bone-matrix palette technique is the same architecture used by Assassin's Creed Unity, Total War: Warhammer, and Hitman for their crowd systems. We're using the same core idea, in a Godot fork, with smaller VRAM — our low-poly animals keep textures tiny.</p>