fix cam

src/renderer3d.js

@@ -35,6 +35,25 @@ function setLinePoints(line, a, b) {
   line.geometry.computeBoundingSphere();
 }
 
+function computePoseCenter(near, far) {
+  const points = [];
+  for (const key of JOINT_KEYS) {
+    const np = near?.[key];
+    const fp = far?.[key];
+    if (np && Number.isFinite(np.x) && Number.isFinite(np.y)) points.push(np);
+    if (fp && Number.isFinite(fp.x) && Number.isFinite(fp.y)) points.push(fp);
+  }
+  if (!points.length) return null;
+
+  let sx = 0;
+  let sy = 0;
+  for (const p of points) {
+    sx += p.x;
+    sy += p.y;
+  }
+  return { x: sx / points.length, y: sy / points.length };
+}
+
 export function create3DRenderer(mountEl) {
   const scene = new THREE.Scene();
   scene.background = new THREE.Color(0x0f1116);
@@ -52,6 +71,9 @@ export function create3DRenderer(mountEl) {
   controls.target.set(0, 0, 0);
   controls.update();
 
+  const trackedTarget = new THREE.Vector3(0, 0, 0);
+  let hasTrackedTarget = false;
+
   scene.add(new THREE.AmbientLight(0xffffff, 0.65));
 
   const keyLight = new THREE.DirectionalLight(0xffffff, 0.55);
@@ -159,6 +181,21 @@ export function create3DRenderer(mountEl) {
       grid.position.y = -floorY;
     }
 
+    const center = computePoseCenter(near, far);
+    if (center) {
+      const nextTarget = new THREE.Vector3(center.x, -center.y, 0);
+      if (!hasTrackedTarget) {
+        trackedTarget.copy(nextTarget);
+        controls.target.copy(nextTarget);
+        hasTrackedTarget = true;
+      } else {
+        const delta = nextTarget.clone().sub(trackedTarget);
+        trackedTarget.copy(nextTarget);
+        camera.position.add(delta);
+        controls.target.lerp(nextTarget, 0.2);
+      }
+    }
+
     controls.update();
     renderer.render(scene, camera);
   }