public/bluebey-studio: 鼻ちょうちんの追従とひげを修正

鼻ちょうちんの位置が、カメラ移動やポーズ変更のあとに飛ぶ問題を修正。位置はボーン局所座標で持ち、スライダーのオフセットは体の向きに追従させた。寝ている動きでは鼻ちょうちんを自動で表示する。

ひげは「猫」に左右の間隔スライダーを追加し、太さを変えずに大きくできるようにした。カイゼルは先をダリ風のカールにした。

1 files changed, 22 insertions, 8 deletions

diff --git a/public/bluebey-studio/src/main.js b/public/bluebey-studio/src/main.js
index 1f6ad6e..c7e6501 100644
--- a/public/bluebey-studio/src/main.js
+++ b/public/bluebey-studio/src/main.js
@@ -275,13 +275,15 @@ async function init() {
     if (!group) return;
     group.visible = snot?.enabled === true;
     if (!group.visible) return;
+    // The offsets are applied in the *bone's* frame, along the world axes measured
+    // once at rest, so the bubble travels with the body. Recomputing them against
+    // the live world matrix made it snap back whenever the body had moved.
     const k = 0.01; // artwork px -> world units, enough to nudge the bubble
-    const target = group.userData.baseWorld.clone().add(new THREE.Vector3(
-      (snot.offsetX ?? 0) * k,
-      (snot.offsetY ?? 0) * k,
-      (snot.offsetZ ?? 0) * k,
-    ));
-    group.position.copy(group.userData.bone.worldToLocal(target));
+    const { localBase, axes } = group.userData;
+    group.position.copy(localBase)
+      .addScaledVector(axes.x, (snot.offsetX ?? 0) * k)
+      .addScaledVector(axes.y, (snot.offsetY ?? 0) * k)
+      .addScaledVector(axes.z, (snot.offsetZ ?? 0) * k);
     group.userData.baseScale = Number.isFinite(snot.size) ? snot.size : 1;
     group.scale.setScalar(group.userData.baseScale);
     group.userData.material.color.set(snot.color ?? '#dfe8ff');
@@ -326,8 +328,20 @@ async function init() {
     group.add(bubble);
     const bone = master.bone;
     const baseWorld = centre.clone().add(new THREE.Vector3(radius * 1.9, -radius * 0.85, radius * 0.7));
-    group.position.copy(bone.worldToLocal(baseWorld.clone()));
-    group.userData = { bubble, material, bone, baseWorld, baseScale: 1 };
+    const localBase = bone.worldToLocal(baseWorld.clone());
+    // World-axis directions expressed in the bone's frame, captured at rest: the
+    // sliders keep meaning "right / up / towards the viewer" while the bubble rides
+    // with the body.
+    const boneQuat = new THREE.Quaternion();
+    bone.getWorldQuaternion(boneQuat);
+    const invQuat = boneQuat.clone().invert();
+    const axes = {
+      x: new THREE.Vector3(1, 0, 0).applyQuaternion(invQuat),
+      y: new THREE.Vector3(0, 1, 0).applyQuaternion(invQuat),
+      z: new THREE.Vector3(0, 0, 1).applyQuaternion(invQuat),
+    };
+    group.position.copy(localBase);
+    group.userData = { bubble, material, bone, localBase, axes, baseScale: 1 };
     group.visible = false;
     bone.add(group);
     return group;