ModelTranslator: use adaptive ray distance in bake (auto), report source

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Tools/ModelTranslator/bl_bake.py

@@ -98,6 +98,30 @@ def _import_fbx_joined(path, warnings):
     return obj
 
 
+def _measure_separation(low, high, limit=10000):
+    """低模面心到高模表面最近距离数组（供自适应射线）。超 limit 面则均匀采样。
+    高模 BVH 无命中的面丢弃；返回距离列表（可能为空）。"""
+    from mathutils.bvhtree import BVHTree
+    hv = [high.matrix_world @ v.co for v in high.data.vertices]
+    hp = [tuple(p.vertices) for p in high.data.polygons]
+    bvh = BVHTree.FromPolygons(hv, hp, all_triangles=False)
+    polys = low.data.polygons
+    n = len(polys)
+    if n == 0:
+        return []
+    if n <= limit:
+        idxs = range(n)
+    else:
+        idxs = [round(i * (n - 1) / float(limit - 1)) for i in range(limit)]
+    mw = low.matrix_world
+    dists = []
+    for i in idxs:
+        hit = bvh.find_nearest(mw @ polys[i].center)
+        if hit[0] is not None and hit[3] is not None:
+            dists.append(hit[3])
+    return dists
+
+
 def _setup_bake_target(low, stem):
     """低模换成单一烘焙材质，返回接收烘焙结果的 image 节点。"""
     import bpy
@@ -210,7 +234,25 @@ def main():
                         % (BBOX_TOL * 100,
                            [round(d, 3) for d in high_dims],
                            [round(d, 3) for d in low_dims]))
-    ray = estimate_ray_distance(low_dims) if ray_arg == "auto" else float(ray_arg)
+    if ray_arg != "auto":
+        ray = float(ray_arg)
+        ray_info = {"source": "explicit", "distance_p99": None,
+                    "value": ray, "capped": False}
+    else:
+        dists = _measure_separation(low, high)
+        try:
+            if not dists:
+                raise ValueError("低模面心到高模无有效最近距离")
+            ray_info = adaptive_ray_distance(dists, low_dims)
+            ray_info["source"] = "adaptive"
+            ray = ray_info["value"]
+            if ray_info["capped"]:
+                warnings.append("自适应射线达包围盒对角线 1% 上限，请检查高低模对应关系")
+        except ValueError as e:
+            ray = estimate_ray_distance(low_dims)
+            ray_info = {"source": "fixed_fallback", "distance_p99": None,
+                        "value": ray, "capped": False}
+            warnings.append("自适应射线测量失败（%s），回退固定射线" % e)
 
     stem = output_stem(os.path.splitext(os.path.basename(low_fbx))[0])
     os.makedirs(outdir, exist_ok=True)
@@ -238,9 +280,13 @@ def main():
     bpy.ops.export_scene.fbx(filepath=out_fbx, use_selection=True,
                              path_mode='STRIP', embed_textures=False)
 
+    ray_info = dict(ray_info)
+    ray_info["distance_p99"] = (None if ray_info["distance_p99"] is None
+                                else round(ray_info["distance_p99"], 6))
+    ray_info["value"] = round(ray_info["value"], 6)
     print("MT_SUMMARY " + json.dumps(
         {"stem": stem, "fbx": os.path.basename(out_fbx), "outputs": outputs,
-         "size": size, "ray_distance": round(ray, 6),
+         "size": size, "ray_distance": round(ray, 6), "ray": ray_info,
          "high_tris": len(high.data.polygons), "low_tris": len(low.data.polygons),
          "warnings": warnings}, ensure_ascii=False))
 

Tools/ModelTranslator/model_bake.py

@@ -33,6 +33,11 @@ def main():
                            blender_args=("-t", "1"))
     print("== %s（高 %d 面 / 低 %d 面，射线距离 %.4f）-> %s" %
           (s["stem"], s["high_tris"], s["low_tris"], s["ray_distance"], outdir))
+    r = s.get("ray", {})
+    p99 = "n/a" if r.get("distance_p99") is None else "%.4f" % r["distance_p99"]
+    print("  射线: 来源=%s P99=%s 距离=%.4f%s" %
+          (r.get("source", "?"), p99, r.get("value", s["ray_distance"]),
+           "（已夹取）" if r.get("capped") else ""))
     for name, fname in s["outputs"].items():
         print("  %-10s %s" % (name, fname))
     for w in s["warnings"]: