From 8505abf52e42f4441d9d53baf4c31a2ec7123400 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Sepp=C3=A4nen?=
 <40791699+kijai@users.noreply.github.com>
Date: Wed, 13 May 2026 18:33:53 +0300
Subject: [PATCH] feat: Extend Save3D to save vertex colors and textures
 (CORE-189) (#13824)

Split GLB save logic out of nodes_hunyuan3d.py into a new nodes_save_3d.py, and extend the writer to support UVs, per-vertex colors, and embedded baseColor textures.

Extend the MESH type with optional uvs, vertex_colors, and texture fields so meshes can carry texture data through the graph.

Add pack_variable_mesh_batch / get_mesh_batch_item helpers and switch VoxelToMesh / VoxelToMeshBasic to use them so batches with differing vertex/face counts no longer fail at torch.stack.
---
 comfy_api/latest/_util/geometry_types.py |  21 +-
 comfy_extras/nodes_hunyuan3d.py          | 211 +-----------
 comfy_extras/nodes_save_3d.py            | 396 +++++++++++++++++++++++
 nodes.py                                 |   1 +
 4 files changed, 422 insertions(+), 207 deletions(-)
 create mode 100644 comfy_extras/nodes_save_3d.py

diff --git a/comfy_api/latest/_util/geometry_types.py b/comfy_api/latest/_util/geometry_types.py
index b586fceb3..cdde60b10 100644
--- a/comfy_api/latest/_util/geometry_types.py
+++ b/comfy_api/latest/_util/geometry_types.py
@@ -12,9 +12,24 @@ class VOXEL:
 
 
 class MESH:
-    def __init__(self, vertices: torch.Tensor, faces: torch.Tensor):
-        self.vertices = vertices
-        self.faces = faces
+    def __init__(self, vertices: torch.Tensor, faces: torch.Tensor,
+                 uvs: torch.Tensor | None = None,
+                 vertex_colors: torch.Tensor | None = None,
+                 texture: torch.Tensor | None = None,
+                 vertex_counts: torch.Tensor | None = None,
+                 face_counts: torch.Tensor | None = None):
+
+        assert (vertex_counts is None) == (face_counts is None), \
+            "vertex_counts and face_counts must be provided together (both or neither)"
+        self.vertices = vertices            # vertices: (B, N, 3)
+        self.faces = faces                  # faces: (B, M, 3)
+        self.uvs = uvs                      # uvs: (B, N, 2)
+        self.vertex_colors = vertex_colors  # vertex_colors: (B, N, 3 or 4)
+        self.texture = texture              # texture: (B, H, W, 3)
+        # When vertices/faces are zero-padded to a common N/M across the batch (variable-size mesh batch),
+        # these hold the real per-item lengths (B,). None means rows are uniform and no slicing is needed.
+        self.vertex_counts = vertex_counts
+        self.face_counts = face_counts
 
 
 class File3D:
diff --git a/comfy_extras/nodes_hunyuan3d.py b/comfy_extras/nodes_hunyuan3d.py
index bf18ecb88..403eb855b 100644
--- a/comfy_extras/nodes_hunyuan3d.py
+++ b/comfy_extras/nodes_hunyuan3d.py
@@ -1,12 +1,7 @@
 import torch
-import os
-import json
-import struct
-import numpy as np
 from comfy.ldm.modules.diffusionmodules.mmdit import get_1d_sincos_pos_embed_from_grid_torch
-import folder_paths
 import comfy.model_management
-from comfy.cli_args import args
+from comfy_extras.nodes_save_3d import pack_variable_mesh_batch
 from typing_extensions import override
 from comfy_api.latest import ComfyExtension, IO, Types
 from comfy_api.latest._util import MESH, VOXEL  # only for backward compatibility if someone import it from this file (will be removed later) # noqa
@@ -444,7 +439,9 @@ class VoxelToMeshBasic(IO.ComfyNode):
             vertices.append(v)
             faces.append(f)
 
-        return IO.NodeOutput(Types.MESH(torch.stack(vertices), torch.stack(faces)))
+        if vertices and all(v.shape == vertices[0].shape for v in vertices) and all(f.shape == faces[0].shape for f in faces):
+            return IO.NodeOutput(Types.MESH(torch.stack(vertices), torch.stack(faces)))
+        return IO.NodeOutput(pack_variable_mesh_batch(vertices, faces))
 
     decode = execute  # TODO: remove
 
@@ -481,206 +478,13 @@ class VoxelToMesh(IO.ComfyNode):
             vertices.append(v)
             faces.append(f)
 
-        return IO.NodeOutput(Types.MESH(torch.stack(vertices), torch.stack(faces)))
+        if vertices and all(v.shape == vertices[0].shape for v in vertices) and all(f.shape == faces[0].shape for f in faces):
+            return IO.NodeOutput(Types.MESH(torch.stack(vertices), torch.stack(faces)))
+        return IO.NodeOutput(pack_variable_mesh_batch(vertices, faces))
 
     decode = execute  # TODO: remove
 
 
-def save_glb(vertices, faces, filepath, metadata=None):
-    """
-    Save PyTorch tensor vertices and faces as a GLB file without external dependencies.
-
-    Parameters:
-    vertices: torch.Tensor of shape (N, 3) - The vertex coordinates
-    faces: torch.Tensor of shape (M, 3) - The face indices (triangle faces)
-    filepath: str - Output filepath (should end with .glb)
-    """
-
-    # Convert tensors to numpy arrays
-    vertices_np = vertices.cpu().numpy().astype(np.float32)
-    faces_np = faces.cpu().numpy().astype(np.uint32)
-
-    vertices_buffer = vertices_np.tobytes()
-    indices_buffer = faces_np.tobytes()
-
-    def pad_to_4_bytes(buffer):
-        padding_length = (4 - (len(buffer) % 4)) % 4
-        return buffer + b'\x00' * padding_length
-
-    vertices_buffer_padded = pad_to_4_bytes(vertices_buffer)
-    indices_buffer_padded = pad_to_4_bytes(indices_buffer)
-
-    buffer_data = vertices_buffer_padded + indices_buffer_padded
-
-    vertices_byte_length = len(vertices_buffer)
-    vertices_byte_offset = 0
-    indices_byte_length = len(indices_buffer)
-    indices_byte_offset = len(vertices_buffer_padded)
-
-    gltf = {
-        "asset": {"version": "2.0", "generator": "ComfyUI"},
-        "buffers": [
-            {
-                "byteLength": len(buffer_data)
-            }
-        ],
-        "bufferViews": [
-            {
-                "buffer": 0,
-                "byteOffset": vertices_byte_offset,
-                "byteLength": vertices_byte_length,
-                "target": 34962  # ARRAY_BUFFER
-            },
-            {
-                "buffer": 0,
-                "byteOffset": indices_byte_offset,
-                "byteLength": indices_byte_length,
-                "target": 34963  # ELEMENT_ARRAY_BUFFER
-            }
-        ],
-        "accessors": [
-            {
-                "bufferView": 0,
-                "byteOffset": 0,
-                "componentType": 5126,  # FLOAT
-                "count": len(vertices_np),
-                "type": "VEC3",
-                "max": vertices_np.max(axis=0).tolist(),
-                "min": vertices_np.min(axis=0).tolist()
-            },
-            {
-                "bufferView": 1,
-                "byteOffset": 0,
-                "componentType": 5125,  # UNSIGNED_INT
-                "count": faces_np.size,
-                "type": "SCALAR"
-            }
-        ],
-        "meshes": [
-            {
-                "primitives": [
-                    {
-                        "attributes": {
-                            "POSITION": 0
-                        },
-                        "indices": 1,
-                        "mode": 4  # TRIANGLES
-                    }
-                ]
-            }
-        ],
-        "nodes": [
-            {
-                "mesh": 0
-            }
-        ],
-        "scenes": [
-            {
-                "nodes": [0]
-            }
-        ],
-        "scene": 0
-    }
-
-    if metadata is not None:
-        gltf["asset"]["extras"] = metadata
-
-    # Convert the JSON to bytes
-    gltf_json = json.dumps(gltf).encode('utf8')
-
-    def pad_json_to_4_bytes(buffer):
-        padding_length = (4 - (len(buffer) % 4)) % 4
-        return buffer + b' ' * padding_length
-
-    gltf_json_padded = pad_json_to_4_bytes(gltf_json)
-
-    # Create the GLB header
-    # Magic glTF
-    glb_header = struct.pack('<4sII', b'glTF', 2, 12 + 8 + len(gltf_json_padded) + 8 + len(buffer_data))
-
-    # Create JSON chunk header (chunk type 0)
-    json_chunk_header = struct.pack('<II', len(gltf_json_padded), 0x4E4F534A)  # "JSON" in little endian
-
-    # Create BIN chunk header (chunk type 1)
-    bin_chunk_header = struct.pack('<II', len(buffer_data), 0x004E4942)  # "BIN\0" in little endian
-
-    # Write the GLB file
-    with open(filepath, 'wb') as f:
-        f.write(glb_header)
-        f.write(json_chunk_header)
-        f.write(gltf_json_padded)
-        f.write(bin_chunk_header)
-        f.write(buffer_data)
-
-    return filepath
-
-
-class SaveGLB(IO.ComfyNode):
-    @classmethod
-    def define_schema(cls):
-        return IO.Schema(
-            node_id="SaveGLB",
-            display_name="Save 3D Model",
-            search_aliases=["export 3d model", "save mesh"],
-            category="3d",
-            essentials_category="Basics",
-            is_output_node=True,
-            inputs=[
-                IO.MultiType.Input(
-                    IO.Mesh.Input("mesh"),
-                    types=[
-                        IO.File3DGLB,
-                        IO.File3DGLTF,
-                        IO.File3DOBJ,
-                        IO.File3DFBX,
-                        IO.File3DSTL,
-                        IO.File3DUSDZ,
-                        IO.File3DAny,
-                    ],
-                    tooltip="Mesh or 3D file to save",
-                ),
-                IO.String.Input("filename_prefix", default="3d/ComfyUI"),
-            ],
-            hidden=[IO.Hidden.prompt, IO.Hidden.extra_pnginfo]
-        )
-
-    @classmethod
-    def execute(cls, mesh: Types.MESH | Types.File3D, filename_prefix: str) -> IO.NodeOutput:
-        full_output_folder, filename, counter, subfolder, filename_prefix = folder_paths.get_save_image_path(filename_prefix, folder_paths.get_output_directory())
-        results = []
-
-        metadata = {}
-        if not args.disable_metadata:
-            if cls.hidden.prompt is not None:
-                metadata["prompt"] = json.dumps(cls.hidden.prompt)
-            if cls.hidden.extra_pnginfo is not None:
-                for x in cls.hidden.extra_pnginfo:
-                    metadata[x] = json.dumps(cls.hidden.extra_pnginfo[x])
-
-        if isinstance(mesh, Types.File3D):
-            # Handle File3D input - save BytesIO data to output folder
-            ext = mesh.format or "glb"
-            f = f"{filename}_{counter:05}_.{ext}"
-            mesh.save_to(os.path.join(full_output_folder, f))
-            results.append({
-                "filename": f,
-                "subfolder": subfolder,
-                "type": "output"
-            })
-        else:
-            # Handle Mesh input - save vertices and faces as GLB
-            for i in range(mesh.vertices.shape[0]):
-                f = f"{filename}_{counter:05}_.glb"
-                save_glb(mesh.vertices[i], mesh.faces[i], os.path.join(full_output_folder, f), metadata)
-                results.append({
-                    "filename": f,
-                    "subfolder": subfolder,
-                    "type": "output"
-                })
-                counter += 1
-        return IO.NodeOutput(ui={"3d": results})
-
-
 class Hunyuan3dExtension(ComfyExtension):
     @override
     async def get_node_list(self) -> list[type[IO.ComfyNode]]:
@@ -691,7 +495,6 @@ class Hunyuan3dExtension(ComfyExtension):
             VAEDecodeHunyuan3D,
             VoxelToMeshBasic,
             VoxelToMesh,
-            SaveGLB,
         ]
 
 
diff --git a/comfy_extras/nodes_save_3d.py b/comfy_extras/nodes_save_3d.py
new file mode 100644
index 000000000..c03524246
--- /dev/null
+++ b/comfy_extras/nodes_save_3d.py
@@ -0,0 +1,396 @@
+"""Save-side 3D nodes: mesh packing/slicing helpers + GLB writer + SaveGLB node."""
+
+import json
+import logging
+import os
+import struct
+from io import BytesIO
+
+import numpy as np
+from PIL import Image
+import torch
+from typing_extensions import override
+
+import folder_paths
+from comfy.cli_args import args
+from comfy_api.latest import ComfyExtension, IO, Types
+
+
+def pack_variable_mesh_batch(vertices, faces, colors=None, uvs=None, texture=None):
+    # Pack lists of (Nᵢ, *) vertex/face/color/uv tensors into padded batched tensors,
+    # stashing per-item lengths as runtime attrs so consumers can recover the real slice.
+    # colors and uvs are 1:1 with vertices, so they're padded to max_vertices and read with vertex_counts.
+    # texture is (B, H, W, 3) — passed through unchanged
+    batch_size = len(vertices)
+    max_vertices = max(v.shape[0] for v in vertices)
+    max_faces = max(f.shape[0] for f in faces)
+
+    packed_vertices = vertices[0].new_zeros((batch_size, max_vertices, vertices[0].shape[1]))
+    packed_faces = faces[0].new_zeros((batch_size, max_faces, faces[0].shape[1]))
+    vertex_counts = torch.tensor([v.shape[0] for v in vertices], device=vertices[0].device, dtype=torch.int64)
+    face_counts = torch.tensor([f.shape[0] for f in faces], device=faces[0].device, dtype=torch.int64)
+
+    for i, (v, f) in enumerate(zip(vertices, faces)):
+        packed_vertices[i, :v.shape[0]] = v
+        packed_faces[i, :f.shape[0]] = f
+
+    packed_colors = None
+    if colors is not None:
+        packed_colors = colors[0].new_zeros((batch_size, max_vertices, colors[0].shape[1]))
+        for i, c in enumerate(colors):
+            assert c.shape[0] == vertices[i].shape[0], (
+                f"vertex_colors[{i}] has {c.shape[0]} entries, expected {vertices[i].shape[0]} (1:1 with vertices)"
+            )
+            packed_colors[i, :c.shape[0]] = c
+
+    packed_uvs = None
+    if uvs is not None:
+        packed_uvs = uvs[0].new_zeros((batch_size, max_vertices, uvs[0].shape[1]))
+        for i, u in enumerate(uvs):
+            assert u.shape[0] == vertices[i].shape[0], (
+                f"uvs[{i}] has {u.shape[0]} entries, expected {vertices[i].shape[0]} (1:1 with vertices)"
+            )
+            packed_uvs[i, :u.shape[0]] = u
+
+    return Types.MESH(packed_vertices, packed_faces,
+                      uvs=packed_uvs, vertex_colors=packed_colors, texture=texture,
+                      vertex_counts=vertex_counts, face_counts=face_counts)
+
+
+def get_mesh_batch_item(mesh, index):
+    # Returns (vertices, faces, colors, uvs) for batch index, slicing to real lengths
+    # if the mesh carries per-item counts (variable-size batch).
+    v_colors = getattr(mesh, "vertex_colors", None)
+    v_uvs = getattr(mesh, "uvs", None)
+    if getattr(mesh, "vertex_counts", None) is not None:
+        vertex_count = int(mesh.vertex_counts[index].item())
+        face_count = int(mesh.face_counts[index].item())
+        vertices = mesh.vertices[index, :vertex_count]
+        faces = mesh.faces[index, :face_count]
+        colors = v_colors[index, :vertex_count] if v_colors is not None else None
+        uvs = v_uvs[index, :vertex_count] if v_uvs is not None else None
+        return vertices, faces, colors, uvs
+
+    colors = v_colors[index] if v_colors is not None else None
+    uvs = v_uvs[index] if v_uvs is not None else None
+    return mesh.vertices[index], mesh.faces[index], colors, uvs
+
+
+def save_glb(vertices, faces, filepath, metadata=None,
+             uvs=None, vertex_colors=None, texture_image=None):
+    """
+    Save PyTorch tensor vertices and faces as a GLB file without external dependencies.
+
+    Parameters:
+    vertices: torch.Tensor of shape (N, 3) - The vertex coordinates
+    faces: torch.Tensor of shape (M, 3) - The face indices (triangle faces)
+    filepath: str - Output filepath (should end with .glb)
+    metadata: dict - Optional asset.extras metadata
+    uvs: torch.Tensor of shape (N, 2) - Optional per-vertex texture coordinates
+    vertex_colors: torch.Tensor of shape (N, 3) or (N, 4) - Optional per-vertex colors in [0, 1]
+    texture_image: PIL.Image - Optional baseColor texture, embedded as PNG
+    """
+
+    # Convert tensors to numpy arrays
+    vertices_np = vertices.cpu().numpy().astype(np.float32)
+    faces_signed = faces.cpu().numpy().astype(np.int64)
+    uvs_np = uvs.cpu().numpy().astype(np.float32) if uvs is not None else None
+    colors_np = vertex_colors.cpu().numpy().astype(np.float32) if vertex_colors is not None else None
+    if colors_np is not None:
+        colors_np = np.clip(colors_np, 0.0, 1.0)
+
+    n_verts = vertices_np.shape[0]
+    if n_verts == 0:
+        raise ValueError("save_glb: vertices is empty")
+    if faces_signed.size > 0:
+        fmin = int(faces_signed.min())
+        fmax = int(faces_signed.max())
+        if fmin < 0 or fmax >= n_verts:
+            raise ValueError(
+                f"save_glb: face index out of range [0, {n_verts}): min={fmin}, max={fmax}"
+            )
+    if uvs_np is not None and uvs_np.shape[0] != n_verts:
+        raise ValueError(
+            f"save_glb: uvs has {uvs_np.shape[0]} entries but vertex count is {n_verts}"
+        )
+    if colors_np is not None and colors_np.shape[0] != n_verts:
+        raise ValueError(
+            f"save_glb: vertex_colors has {colors_np.shape[0]} entries but vertex count is {n_verts}"
+        )
+    faces_np = faces_signed.astype(np.uint32)
+    texture_png_bytes = None
+    if texture_image is not None:
+        buf = BytesIO()
+        texture_image.save(buf, format="PNG")
+        texture_png_bytes = buf.getvalue()
+
+    vertices_buffer = vertices_np.tobytes()
+    indices_buffer = faces_np.tobytes()
+    uvs_buffer = uvs_np.tobytes() if uvs_np is not None else b""
+    colors_buffer = colors_np.tobytes() if colors_np is not None else b""
+    texture_buffer = texture_png_bytes if texture_png_bytes is not None else b""
+
+    def pad_to_4_bytes(buffer):
+        padding_length = (4 - (len(buffer) % 4)) % 4
+        return buffer + b'\x00' * padding_length
+
+    vertices_buffer_padded = pad_to_4_bytes(vertices_buffer)
+    indices_buffer_padded = pad_to_4_bytes(indices_buffer)
+    uvs_buffer_padded = pad_to_4_bytes(uvs_buffer)
+    colors_buffer_padded = pad_to_4_bytes(colors_buffer)
+    texture_buffer_padded = pad_to_4_bytes(texture_buffer)
+
+    buffer_data = b"".join([
+        vertices_buffer_padded,
+        indices_buffer_padded,
+        uvs_buffer_padded,
+        colors_buffer_padded,
+        texture_buffer_padded,
+    ])
+
+    vertices_byte_length = len(vertices_buffer)
+    vertices_byte_offset = 0
+    indices_byte_length = len(indices_buffer)
+    indices_byte_offset = len(vertices_buffer_padded)
+    uvs_byte_offset = indices_byte_offset + len(indices_buffer_padded)
+    colors_byte_offset = uvs_byte_offset + len(uvs_buffer_padded)
+    texture_byte_offset = colors_byte_offset + len(colors_buffer_padded)
+
+    buffer_views = [
+        {
+            "buffer": 0,
+            "byteOffset": vertices_byte_offset,
+            "byteLength": vertices_byte_length,
+            "target": 34962  # ARRAY_BUFFER
+        },
+        {
+            "buffer": 0,
+            "byteOffset": indices_byte_offset,
+            "byteLength": indices_byte_length,
+            "target": 34963  # ELEMENT_ARRAY_BUFFER
+        }
+    ]
+    accessors = [
+        {
+            "bufferView": 0,
+            "byteOffset": 0,
+            "componentType": 5126,  # FLOAT
+            "count": len(vertices_np),
+            "type": "VEC3",
+            "max": vertices_np.max(axis=0).tolist(),
+            "min": vertices_np.min(axis=0).tolist()
+        },
+        {
+            "bufferView": 1,
+            "byteOffset": 0,
+            "componentType": 5125,  # UNSIGNED_INT
+            "count": faces_np.size,
+            "type": "SCALAR"
+        }
+    ]
+    primitive_attributes = {"POSITION": 0}
+
+    if uvs_np is not None and len(uvs_np) > 0:
+        buffer_views.append({
+            "buffer": 0,
+            "byteOffset": uvs_byte_offset,
+            "byteLength": len(uvs_buffer),
+            "target": 34962
+        })
+        accessor_idx = len(accessors)
+        accessors.append({
+            "bufferView": len(buffer_views) - 1,
+            "byteOffset": 0,
+            "componentType": 5126,
+            "count": len(uvs_np),
+            "type": "VEC2",
+        })
+        primitive_attributes["TEXCOORD_0"] = accessor_idx
+
+    if colors_np is not None and len(colors_np) > 0:
+        buffer_views.append({
+            "buffer": 0,
+            "byteOffset": colors_byte_offset,
+            "byteLength": len(colors_buffer),
+            "target": 34962
+        })
+        accessor_idx = len(accessors)
+        accessors.append({
+            "bufferView": len(buffer_views) - 1,
+            "byteOffset": 0,
+            "componentType": 5126,
+            "count": len(colors_np),
+            "type": "VEC3" if colors_np.shape[1] == 3 else "VEC4",
+        })
+        primitive_attributes["COLOR_0"] = accessor_idx
+
+    primitive = {
+        "attributes": primitive_attributes,
+        "indices": 1,
+        "mode": 4  # TRIANGLES
+    }
+
+    images = []
+    textures = []
+    samplers = []
+    materials = []
+    if texture_png_bytes is not None and "TEXCOORD_0" in primitive_attributes:
+        buffer_views.append({
+            "buffer": 0,
+            "byteOffset": texture_byte_offset,
+            "byteLength": len(texture_buffer),
+        })
+        images.append({"bufferView": len(buffer_views) - 1, "mimeType": "image/png"})
+        samplers.append({"magFilter": 9729, "minFilter": 9729, "wrapS": 33071, "wrapT": 33071})
+        textures.append({"source": 0, "sampler": 0})
+        materials.append({
+            "pbrMetallicRoughness": {
+                "baseColorTexture": {"index": 0, "texCoord": 0},
+                "metallicFactor": 0.0,
+                "roughnessFactor": 1.0,
+            },
+            "doubleSided": True,
+        })
+        primitive["material"] = 0
+
+    gltf = {
+        "asset": {"version": "2.0", "generator": "ComfyUI"},
+        "buffers": [{"byteLength": len(buffer_data)}],
+        "bufferViews": buffer_views,
+        "accessors": accessors,
+        "meshes": [{"primitives": [primitive]}],
+        "nodes": [{"mesh": 0}],
+        "scenes": [{"nodes": [0]}],
+        "scene": 0,
+    }
+    if images:
+        gltf["images"] = images
+    if samplers:
+        gltf["samplers"] = samplers
+    if textures:
+        gltf["textures"] = textures
+    if materials:
+        gltf["materials"] = materials
+
+    if metadata:
+        gltf["asset"]["extras"] = metadata
+
+    # Convert the JSON to bytes
+    gltf_json = json.dumps(gltf).encode('utf8')
+
+    def pad_json_to_4_bytes(buffer):
+        padding_length = (4 - (len(buffer) % 4)) % 4
+        return buffer + b' ' * padding_length
+
+    gltf_json_padded = pad_json_to_4_bytes(gltf_json)
+
+    # Create the GLB header (a 4-byte ASCII magic identifier glTF)
+    glb_header = struct.pack('<4sII', b'glTF', 2, 12 + 8 + len(gltf_json_padded) + 8 + len(buffer_data))
+
+    # Create JSON chunk header (chunk type 0)
+    json_chunk_header = struct.pack('<II', len(gltf_json_padded), 0x4E4F534A)  # "JSON" in little endian
+
+    # Create BIN chunk header (chunk type 1)
+    bin_chunk_header = struct.pack('<II', len(buffer_data), 0x004E4942)  # "BIN\0" in little endian
+
+    # Write the GLB file
+    with open(filepath, 'wb') as f:
+        f.write(glb_header)
+        f.write(json_chunk_header)
+        f.write(gltf_json_padded)
+        f.write(bin_chunk_header)
+        f.write(buffer_data)
+
+    return filepath
+
+
+class SaveGLB(IO.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return IO.Schema(
+            node_id="SaveGLB",
+            display_name="Save 3D Model",
+            search_aliases=["export 3d model", "save mesh"],
+            category="3d",
+            essentials_category="Basics",
+            is_output_node=True,
+            inputs=[
+                IO.MultiType.Input(
+                    IO.Mesh.Input("mesh"),
+                    types=[
+                        IO.File3DGLB,
+                        IO.File3DGLTF,
+                        IO.File3DOBJ,
+                        IO.File3DFBX,
+                        IO.File3DSTL,
+                        IO.File3DUSDZ,
+                        IO.File3DAny,
+                    ],
+                    tooltip="Mesh or 3D file to save",
+                ),
+                IO.String.Input("filename_prefix", default="3d/ComfyUI"),
+            ],
+            hidden=[IO.Hidden.prompt, IO.Hidden.extra_pnginfo]
+        )
+
+    @classmethod
+    def execute(cls, mesh: Types.MESH | Types.File3D, filename_prefix: str) -> IO.NodeOutput:
+        full_output_folder, filename, counter, subfolder, filename_prefix = folder_paths.get_save_image_path(filename_prefix, folder_paths.get_output_directory())
+        results = []
+
+        metadata = {}
+        if not args.disable_metadata:
+            if cls.hidden.prompt is not None:
+                metadata["prompt"] = json.dumps(cls.hidden.prompt)
+            if cls.hidden.extra_pnginfo is not None:
+                for x in cls.hidden.extra_pnginfo:
+                    metadata[x] = json.dumps(cls.hidden.extra_pnginfo[x])
+
+        if isinstance(mesh, Types.File3D):
+            # Handle File3D input - save BytesIO data to output folder
+            ext = mesh.format or "glb"
+            f = f"{filename}_{counter:05}_.{ext}"
+            mesh.save_to(os.path.join(full_output_folder, f))
+            results.append({
+                "filename": f,
+                "subfolder": subfolder,
+                "type": "output"
+            })
+            counter += 1
+        else:
+            # Handle Mesh input - save vertices and faces as GLB; carry optional UVs / colors / texture.
+            texture_b = getattr(mesh, "texture", None)
+            texture_np = None
+            if texture_b is not None:
+                texture_np = (texture_b.clamp(0.0, 1.0).cpu().numpy() * 255).astype(np.uint8)
+                assert texture_np.ndim == 4 and texture_np.shape[-1] == 3, (
+                    f"texture must be (B, H, W, 3) RGB, got shape {tuple(texture_np.shape)}"
+                )
+            for i in range(mesh.vertices.shape[0]):
+                vertices_i, faces_i, v_colors, uvs_i = get_mesh_batch_item(mesh, i)
+                if vertices_i.shape[0] == 0 or faces_i.shape[0] == 0:
+                    logging.warning(f"SaveGLB: skipping empty mesh at batch index {i}")
+                    continue
+                tex_img = Image.fromarray(texture_np[i], mode="RGB") if texture_np is not None else None
+                f = f"{filename}_{counter:05}_.glb"
+                save_glb(vertices_i, faces_i, os.path.join(full_output_folder, f), metadata,
+                         uvs=uvs_i,
+                         vertex_colors=v_colors,
+                         texture_image=tex_img)
+                results.append({
+                    "filename": f,
+                    "subfolder": subfolder,
+                    "type": "output"
+                })
+                counter += 1
+        return IO.NodeOutput(ui={"3d": results})
+
+
+class Save3DExtension(ComfyExtension):
+    @override
+    async def get_node_list(self) -> list[type[IO.ComfyNode]]:
+        return [SaveGLB]
+
+
+async def comfy_entrypoint() -> Save3DExtension:
+    return Save3DExtension()
diff --git a/nodes.py b/nodes.py
index 78aaaef74..2b63f9fbb 100644
--- a/nodes.py
+++ b/nodes.py
@@ -2436,6 +2436,7 @@ async def init_builtin_extra_nodes():
         "nodes_void.py",
         "nodes_wandancer.py",
         "nodes_hidream_o1.py",
+        "nodes_save_3d.py",
     ]
 
     import_failed = []