From be2587c5f87adc9216d432352c3e3fb549b6712b Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Mon, 25 Aug 2025 10:23:55 +0200
Subject: [PATCH 01/15] add solution to load collada

---
 .../pinocchio/visualize/viser_visualizer.py   | 103 +++++++++++++++---
 1 file changed, 89 insertions(+), 14 deletions(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index 603fc701c1..77f83354c4 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -1,4 +1,5 @@
 import time
+import os
 
 try:
     import hppfcl
@@ -7,12 +8,15 @@
 
 import numpy as np
 
+from trimesh.exchange import dae
 from .. import pinocchio_pywrap_default as pin
 from . import BaseVisualizer
 
 try:
     import trimesh  # Required by viser
     import viser
+    import collada
+
 except ImportError:
     import_viser_succeed = False
 else:
@@ -214,21 +218,92 @@ def loadViewerGeometryObject(self, geometry_object, prefix="", color=None):
 
         self.frames[name] = frame
 
-    def _add_mesh_from_path(self, name, mesh_path, color):
-        """
-        Load a mesh from a file.
-        """
-        mesh = trimesh.load_mesh(mesh_path)
+    def _add_mesh_from_path(self, name, mesh_path, color=None):
+        
+        ext = os.path.splitext(mesh_path)[1].lower()
+        extracted_color = None
+        
+        if ext == ".dae":
+            try:
+                # Load the .dae file using pycollada
+                mesh_collada = collada.Collada(mesh_path)
+                
+                # Method 1: Via pycollada
+                for effect in mesh_collada.effects:
+                    if hasattr(effect, 'diffuse') and effect.diffuse is not None:
+                        # Check if it's a Color object (not a texture)
+                        if hasattr(effect.diffuse, 'color') and effect.diffuse.color is not None:
+                            color_values = effect.diffuse.color
+                            if len(color_values) == 3:
+                                extracted_color = list(color_values) + [1.0]
+                            elif len(color_values) == 4:
+                                extracted_color = list(color_values)
+                            print(f"[INFO] Extracted color from DAE: {extracted_color}")
+                            break
+                        # Alternative: direct access if it's a color array
+                        elif hasattr(effect.diffuse, '__iter__') and len(effect.diffuse) >= 3:
+                            color_values = effect.diffuse
+                            if len(color_values) == 3:
+                                extracted_color = list(color_values) + [1.0]
+                            else:
+                                extracted_color = list(color_values)
+                            print(f"[INFO] Extracted color from DAE (direct): {extracted_color}")
+                            break
+                
+                # Method 2: If pycollada didn't work, parse XML directly
+                if extracted_color is None:
+                    import xml.etree.ElementTree as ET
+                    tree = ET.parse(mesh_path)
+                    root = tree.getroot()
+                    
+                    # Find diffuse tags with color
+                    for diffuse in root.iter():
+                        if diffuse.tag.endswith('diffuse'):
+                            color_elem = diffuse.find('.//color')
+                            if color_elem is not None and color_elem.text:
+                                color_text = color_elem.text.strip().split()
+                                if len(color_text) >= 3:
+                                    try:
+                                        color_values = [float(x) for x in color_text[:4]]
+                                        if len(color_values) == 3:
+                                            extracted_color = color_values + [1.0]
+                                        else:
+                                            extracted_color = color_values
+                                        print(f"[INFO] Extracted color from DAE via XML: {extracted_color}")
+                                        break
+                                    except ValueError:
+                                        continue
+                            
+            except Exception as e:
+                print(f"[ERROR] Failed to extract color from DAE {mesh_path} : {e}")
+                extracted_color = [0.9, 0.9, 0.9, 1.0]  # fallback
+        
+        # Use the extracted color if no color was provided as parameter
         if color is None:
-            return self.viewer.scene.add_mesh_trimesh(name, mesh)
-        else:
-            return self.viewer.scene.add_mesh_simple(
-                name,
-                mesh.vertices,
-                mesh.faces,
-                color=color[:3],
-                opacity=color[3],
-            )
+            color = extracted_color
+        
+        # General case for all formats
+        try:
+            mesh = trimesh.load(mesh_path, force='mesh')
+            
+            if color is None:
+                # No color specified, use the default mesh
+                return self.viewer.scene.add_mesh_trimesh(name, mesh)
+            else:
+                color = [.25,.25,.25,1.]
+                # Specified color (extracted or provided)
+                return self.viewer.scene.add_mesh_simple(
+                    name,
+                    mesh.vertices,
+                    mesh.faces,
+                    color=color[:3],
+                    opacity=color[3]
+                )
+                
+        except Exception as e:
+            print(f"[ERROR] Failed to create mesh {mesh_path} : {e}")
+            return None
+
 
     def _add_mesh_from_convex(self, name, geom, color):
         """

From f7609067fd54b1179394f2ac5c17a934105246fc Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Mon, 25 Aug 2025 10:30:08 +0200
Subject: [PATCH 02/15] add solution to load collada

---
 bindings/python/pinocchio/visualize/viser_visualizer.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index 77f83354c4..03282ea3b9 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -290,7 +290,7 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                 # No color specified, use the default mesh
                 return self.viewer.scene.add_mesh_trimesh(name, mesh)
             else:
-                color = [.25,.25,.25,1.]
+                color = [.25,.25,.20,1.]
                 # Specified color (extracted or provided)
                 return self.viewer.scene.add_mesh_simple(
                     name,

From 2347877eb0e6fe92ebb611fa394e00943c8f52d2 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Tue, 2 Sep 2025 09:14:42 +0200
Subject: [PATCH 03/15] fix default color handling in viser_visualizer.py

---
 .../pinocchio/visualize/viser_visualizer.py   | 121 ++++++------------
 1 file changed, 36 insertions(+), 85 deletions(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index 03282ea3b9..2ce232922b 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -218,92 +218,43 @@ def loadViewerGeometryObject(self, geometry_object, prefix="", color=None):
 
         self.frames[name] = frame
 
-    def _add_mesh_from_path(self, name, mesh_path, color=None):
-        
-        ext = os.path.splitext(mesh_path)[1].lower()
-        extracted_color = None
-        
-        if ext == ".dae":
-            try:
-                # Load the .dae file using pycollada
-                mesh_collada = collada.Collada(mesh_path)
-                
-                # Method 1: Via pycollada
-                for effect in mesh_collada.effects:
-                    if hasattr(effect, 'diffuse') and effect.diffuse is not None:
-                        # Check if it's a Color object (not a texture)
-                        if hasattr(effect.diffuse, 'color') and effect.diffuse.color is not None:
-                            color_values = effect.diffuse.color
-                            if len(color_values) == 3:
-                                extracted_color = list(color_values) + [1.0]
-                            elif len(color_values) == 4:
-                                extracted_color = list(color_values)
-                            print(f"[INFO] Extracted color from DAE: {extracted_color}")
-                            break
-                        # Alternative: direct access if it's a color array
-                        elif hasattr(effect.diffuse, '__iter__') and len(effect.diffuse) >= 3:
-                            color_values = effect.diffuse
-                            if len(color_values) == 3:
-                                extracted_color = list(color_values) + [1.0]
-                            else:
-                                extracted_color = list(color_values)
-                            print(f"[INFO] Extracted color from DAE (direct): {extracted_color}")
-                            break
-                
-                # Method 2: If pycollada didn't work, parse XML directly
-                if extracted_color is None:
-                    import xml.etree.ElementTree as ET
-                    tree = ET.parse(mesh_path)
-                    root = tree.getroot()
-                    
-                    # Find diffuse tags with color
-                    for diffuse in root.iter():
-                        if diffuse.tag.endswith('diffuse'):
-                            color_elem = diffuse.find('.//color')
-                            if color_elem is not None and color_elem.text:
-                                color_text = color_elem.text.strip().split()
-                                if len(color_text) >= 3:
-                                    try:
-                                        color_values = [float(x) for x in color_text[:4]]
-                                        if len(color_values) == 3:
-                                            extracted_color = color_values + [1.0]
-                                        else:
-                                            extracted_color = color_values
-                                        print(f"[INFO] Extracted color from DAE via XML: {extracted_color}")
-                                        break
-                                    except ValueError:
-                                        continue
-                            
-            except Exception as e:
-                print(f"[ERROR] Failed to extract color from DAE {mesh_path} : {e}")
-                extracted_color = [0.9, 0.9, 0.9, 1.0]  # fallback
-        
-        # Use the extracted color if no color was provided as parameter
-        if color is None:
-            color = extracted_color
-        
-        # General case for all formats
-        try:
-            mesh = trimesh.load(mesh_path, force='mesh')
-            
-            if color is None:
-                # No color specified, use the default mesh
-                return self.viewer.scene.add_mesh_trimesh(name, mesh)
-            else:
-                color = [.25,.25,.20,1.]
-                # Specified color (extracted or provided)
-                return self.viewer.scene.add_mesh_simple(
-                    name,
-                    mesh.vertices,
-                    mesh.faces,
-                    color=color[:3],
-                    opacity=color[3]
-                )
-                
-        except Exception as e:
-            print(f"[ERROR] Failed to create mesh {mesh_path} : {e}")
-            return None
+   def _add_mesh_from_path(self, name, mesh_path, color=None):
+        """
+        Load a mesh from a file and add it to the scene.
+        """
+        mesh_collada = collada.Collada(mesh_path)
 
+        for i, (geometry, effect) in enumerate(
+            zip(mesh_collada.geometries, mesh_collada.effects)
+        ):
+            try:
+                # extraction des données
+                vertices = geometry.primitives[0].sources["VERTEX"][0][4].data
+                indices = geometry.primitives[0].indices
+
+                # indices 3D ou 2D
+                if indices.ndim == 3:
+                    faces = indices[:, :, 0]
+                else:
+                    faces = indices
+
+                # gestion de la couleur
+                color = getattr(effect, "diffuse", None)
+
+                if color is None:
+                    mesh = trimesh.load_mesh(mesh_path)
+                    self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
+                else:
+                    self.viewer.scene.add_mesh_simple(
+                        f"{name}_{i}",
+                        vertices,
+                        faces,
+                        color=color[:3],
+                        opacity=color[3],
+                    )
+            except Exception:
+                mesh = trimesh.load_mesh(mesh_path)
+                self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
 
     def _add_mesh_from_convex(self, name, geom, color):
         """

From ea797d480246bd662d4d875edf53650c3c1eceac Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Mon, 22 Sep 2025 09:16:39 +0200
Subject: [PATCH 04/15] change the default robot in viser-viewer.py to test

---
 examples/gepetto-viewer.py |   4 ++--
 examples/viser-viewer.py   |   4 ++--
 leap.mp4                   | Bin 0 -> 8 bytes
 3 files changed, 4 insertions(+), 4 deletions(-)
 create mode 100644 leap.mp4

diff --git a/examples/gepetto-viewer.py b/examples/gepetto-viewer.py
index 95faf6ed3b..b996b9b946 100644
--- a/examples/gepetto-viewer.py
+++ b/examples/gepetto-viewer.py
@@ -11,8 +11,8 @@
 # Load the URDF model.
 model_path = Path(os.environ.get("EXAMPLE_ROBOT_DATA_MODEL_DIR"))
 mesh_dir = model_path.parent.parent
-urdf_filename = "talos_reduced.urdf"
-urdf_model_path = model_path / "talos_data/robots" / urdf_filename
+urdf_filename = "panda.urdf"
+urdf_model_path = model_path / "panda_description/urdf" / urdf_filename
 
 model, collision_model, visual_model = pin.buildModelsFromUrdf(
     urdf_model_path, mesh_dir, pin.JointModelFreeFlyer()
diff --git a/examples/viser-viewer.py b/examples/viser-viewer.py
index dd4fbe20e1..33971c6470 100644
--- a/examples/viser-viewer.py
+++ b/examples/viser-viewer.py
@@ -17,8 +17,8 @@
 mesh_dir = pinocchio_model_dir
 # urdf_filename = "talos_reduced.urdf"
 # urdf_model_path = join(join(model_path,"talos_data/robots"),urdf_filename)
-urdf_filename = "solo.urdf"
-urdf_model_path = model_path / "solo_description/robots" / urdf_filename
+urdf_filename = "tiago.urdf"
+urdf_model_path = model_path / "tiago_description/robots" / urdf_filename
 
 model, collision_model, visual_model = pin.buildModelsFromUrdf(
     urdf_model_path, mesh_dir, pin.JointModelFreeFlyer()
diff --git a/leap.mp4 b/leap.mp4
new file mode 100644
index 0000000000000000000000000000000000000000..997c69fe8f92889a927c5ad5de83611677d727a9
GIT binary patch
literal 8
McmebD)M5Yu00m0`y#N3J

literal 0
HcmV?d00001


From 68c539c95649961c2206f4a421db7668d140a66b Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Tue, 30 Sep 2025 09:56:07 +0200
Subject: [PATCH 05/15] change the function add_mesh_from_path to load color
 with collada

---
 .../pinocchio/visualize/viser_visualizer.py   | 84 ++++++++++++-------
 1 file changed, 52 insertions(+), 32 deletions(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index 2ce232922b..6f1c0f20dd 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -218,43 +218,63 @@ def loadViewerGeometryObject(self, geometry_object, prefix="", color=None):
 
         self.frames[name] = frame
 
-   def _add_mesh_from_path(self, name, mesh_path, color=None):
-        """
-        Load a mesh from a file and add it to the scene.
-        """
-        mesh_collada = collada.Collada(mesh_path)
-
-        for i, (geometry, effect) in enumerate(
-            zip(mesh_collada.geometries, mesh_collada.effects)
-        ):
-            try:
-                # extraction des données
-                vertices = geometry.primitives[0].sources["VERTEX"][0][4].data
-                indices = geometry.primitives[0].indices
+    def _add_mesh_from_path(self, name, mesh_path, color=None):
+        ext = os.path.splitext(mesh_path)[1].lower()
+        print(f"[DEBUG] _add_mesh_from_path: {mesh_path} (ext={ext})")
 
-                # indices 3D ou 2D
-                if indices.ndim == 3:
-                    faces = indices[:, :, 0]
-                else:
-                    faces = indices
+        if ext not in [".dae", ".stl", ".obj"]:
+            print(f"[WARNING] Ignoring non-mesh file: {mesh_path}")
+            return
 
-                # gestion de la couleur
-                color = getattr(effect, "diffuse", None)
+        if ext == ".dae":
+            try:
+                mesh_collada = collada.Collada(mesh_path)
 
-                if color is None:
+                if len(mesh_collada.effects) < len(mesh_collada.geometries):
                     mesh = trimesh.load_mesh(mesh_path)
-                    self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
-                else:
-                    self.viewer.scene.add_mesh_simple(
-                        f"{name}_{i}",
-                        vertices,
-                        faces,
-                        color=color[:3],
-                        opacity=color[3],
-                    )
-            except Exception:
+                    self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
+                    return
+
+                for i, (geometry, effect) in enumerate(
+                    zip(mesh_collada.geometries, mesh_collada.effects)
+                ):
+                    try:
+                        vertices = geometry.primitives[0].sources["VERTEX"][0][4].data
+                        indices = geometry.primitives[0].indices
+
+                        if indices.ndim == 3:
+                            faces = indices[:, :, 0]
+                        else:
+                            faces = indices
+
+                        color = getattr(effect, "diffuse", None)
+
+                        if color is None:
+                            mesh = trimesh.load_mesh(mesh_path)
+                            self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
+                        else:
+                            self.viewer.scene.add_mesh_simple(
+                                f"{name}_{i}",
+                                vertices,
+                                faces,
+                                color=color[:3],
+                                opacity=color[3],
+                            )
+
+                    except Exception as e:
+                        print(f"[ERROR] Collada parsing failed: {e}")
+                        mesh = trimesh.load_mesh(mesh_path)
+                        self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
+
+            except Exception as e:
+                print(f"[ERROR] Failed to load {mesh_path} as .dae: {e}")
                 mesh = trimesh.load_mesh(mesh_path)
-                self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
+                self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
+
+        else:
+            # Cas STL / OBJ → directement avec trimesh
+            mesh = trimesh.load_mesh(mesh_path)
+            self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
 
     def _add_mesh_from_convex(self, name, geom, color):
         """

From ac14f5f6556ea27b753b74d8872aad2673c62f54 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Tue, 7 Oct 2025 15:12:42 +0200
Subject: [PATCH 06/15] Ensure all geometry types are correctly handled to
 prevent NoneType errors.

---
 bindings/python/pinocchio/visualize/viser_visualizer.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index 6f1c0f20dd..ca9104bfc6 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -220,8 +220,7 @@ def loadViewerGeometryObject(self, geometry_object, prefix="", color=None):
 
     def _add_mesh_from_path(self, name, mesh_path, color=None):
         ext = os.path.splitext(mesh_path)[1].lower()
-        print(f"[DEBUG] _add_mesh_from_path: {mesh_path} (ext={ext})")
-
+        
         if ext not in [".dae", ".stl", ".obj"]:
             print(f"[WARNING] Ignoring non-mesh file: {mesh_path}")
             return
@@ -272,7 +271,6 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                 self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
 
         else:
-            # Cas STL / OBJ → directement avec trimesh
             mesh = trimesh.load_mesh(mesh_path)
             self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
 

From 9decb6c1b71fc592c22febb4b2d846a653462e8c Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Tue, 7 Oct 2025 15:24:36 +0200
Subject: [PATCH 07/15] Ensure all geometry types are correctly handled to
 prevent NoneType errors.

---
 bindings/python/pinocchio/visualize/viser_visualizer.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index ca9104bfc6..eec9c32dd0 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -220,7 +220,7 @@ def loadViewerGeometryObject(self, geometry_object, prefix="", color=None):
 
     def _add_mesh_from_path(self, name, mesh_path, color=None):
         ext = os.path.splitext(mesh_path)[1].lower()
-        
+
         if ext not in [".dae", ".stl", ".obj"]:
             print(f"[WARNING] Ignoring non-mesh file: {mesh_path}")
             return

From 7e2e7a929f5a775044e0046f664ef3f62eb72396 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Fri, 10 Oct 2025 09:54:50 +0200
Subject: [PATCH 08/15] handle incorrect faces array shape in COLLADA mesh
 loading

---
 .../pinocchio/visualize/viser_visualizer.py   | 68 ++++++++++++-------
 1 file changed, 44 insertions(+), 24 deletions(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index eec9c32dd0..a0c81b410a 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -219,60 +219,80 @@ def loadViewerGeometryObject(self, geometry_object, prefix="", color=None):
         self.frames[name] = frame
 
     def _add_mesh_from_path(self, name, mesh_path, color=None):
+        """
+        Load a mesh from a file
+        """
         ext = os.path.splitext(mesh_path)[1].lower()
-
-        if ext not in [".dae", ".stl", ".obj"]:
-            print(f"[WARNING] Ignoring non-mesh file: {mesh_path}")
-            return
-
         if ext == ".dae":
             try:
                 mesh_collada = collada.Collada(mesh_path)
-
                 if len(mesh_collada.effects) < len(mesh_collada.geometries):
                     mesh = trimesh.load_mesh(mesh_path)
-                    self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
-                    return
-
+                    return self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
+                
+                frames = []
                 for i, (geometry, effect) in enumerate(
                     zip(mesh_collada.geometries, mesh_collada.effects)
                 ):
                     try:
                         vertices = geometry.primitives[0].sources["VERTEX"][0][4].data
                         indices = geometry.primitives[0].indices
-
+                        
                         if indices.ndim == 3:
                             faces = indices[:, :, 0]
-                        else:
+                        elif indices.ndim == 2:
                             faces = indices
-
+                        elif indices.ndim == 1:
+                            faces = indices.reshape(-1, 3)
+                        else:
+                            raise ValueError(f"indices has an unexpected form: {indices.shape}")
+                        
+                        if faces.shape[-1] != 3:
+                            if faces.size % 3 == 0:
+                                faces = faces.reshape(-1, 3)
+                            else:
+                                raise ValueError(f"Unable to reshape faces in (N, 3): {faces.shape}")
+                        
                         color = getattr(effect, "diffuse", None)
-
                         if color is None:
                             mesh = trimesh.load_mesh(mesh_path)
-                            self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
+                            frame = self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
                         else:
-                            self.viewer.scene.add_mesh_simple(
+                            frame = self.viewer.scene.add_mesh_simple(
                                 f"{name}_{i}",
                                 vertices,
                                 faces,
                                 color=color[:3],
                                 opacity=color[3],
                             )
-
+                        
+                        if frame is None:
+                            frame = self.viewer.scene.add_box(
+                                f"{name}_{i}_placeholder",
+                                (0.001, 0.001, 0.001),
+                                color=(200, 200, 200)
+                            )
+                        frames.append(frame)
+                        
                     except Exception as e:
-                        print(f"[ERROR] Collada parsing failed: {e}")
-                        mesh = trimesh.load_mesh(mesh_path)
-                        self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
-
+                        import traceback
+                        try:
+                            mesh = trimesh.load_mesh(mesh_path)
+                            frame = self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
+                            if frame is not None:
+                                frames.append(frame)
+                        except Exception as e2:
+                            pass
+                
+                return frames[0] if frames else None
+                
             except Exception as e:
-                print(f"[ERROR] Failed to load {mesh_path} as .dae: {e}")
+                import traceback
                 mesh = trimesh.load_mesh(mesh_path)
-                self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
-
+                return self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
         else:
             mesh = trimesh.load_mesh(mesh_path)
-            self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
+            return self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
 
     def _add_mesh_from_convex(self, name, geom, color):
         """

From 16c3bed1de7b7e3c1b652a37f2acd4ef606985e0 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Tue, 14 Oct 2025 10:26:04 +0200
Subject: [PATCH 09/15] improved handling of geometry indices (added explicit
 checks and reshaping)

---
 .../pinocchio/visualize/viser_visualizer.py   | 62 +++++++++++++------
 1 file changed, 44 insertions(+), 18 deletions(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index a0c81b410a..a60b2b662a 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -220,15 +220,23 @@ def loadViewerGeometryObject(self, geometry_object, prefix="", color=None):
 
     def _add_mesh_from_path(self, name, mesh_path, color=None):
         """
-        Load a mesh from a file
+        Load a mesh from a file.
         """
         ext = os.path.splitext(mesh_path)[1].lower()
+        
         if ext == ".dae":
             try:
                 mesh_collada = collada.Collada(mesh_path)
+                
                 if len(mesh_collada.effects) < len(mesh_collada.geometries):
                     mesh = trimesh.load_mesh(mesh_path)
-                    return self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
+                    if color is None:
+                        return self.viewer.scene.add_mesh_trimesh(name, mesh)
+                    else:
+                        return self.viewer.scene.add_mesh_simple(
+                            name, mesh.vertices, mesh.faces,
+                            color=color[:3], opacity=color[3]
+                        )
                 
                 frames = []
                 for i, (geometry, effect) in enumerate(
@@ -245,19 +253,23 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                         elif indices.ndim == 1:
                             faces = indices.reshape(-1, 3)
                         else:
-                            raise ValueError(f"indices has an unexpected form: {indices.shape}")
+                            faces = indices.reshape(-1, 3)
                         
                         if faces.shape[-1] != 3:
                             if faces.size % 3 == 0:
                                 faces = faces.reshape(-1, 3)
-                            else:
-                                raise ValueError(f"Unable to reshape faces in (N, 3): {faces.shape}")
                         
-                        color = getattr(effect, "diffuse", None)
-                        if color is None:
-                            mesh = trimesh.load_mesh(mesh_path)
-                            frame = self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
-                        else:
+                        mesh_color = getattr(effect, "diffuse", None)
+                        
+                        if mesh_color is not None:
+                            frame = self.viewer.scene.add_mesh_simple(
+                                f"{name}_{i}",
+                                vertices,
+                                faces,
+                                color=mesh_color[:3],
+                                opacity=mesh_color[3],
+                            )
+                        elif color is not None:
                             frame = self.viewer.scene.add_mesh_simple(
                                 f"{name}_{i}",
                                 vertices,
@@ -265,6 +277,9 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                                 color=color[:3],
                                 opacity=color[3],
                             )
+                        else:
+                            mesh = trimesh.load_mesh(mesh_path)
+                            frame = self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
                         
                         if frame is None:
                             frame = self.viewer.scene.add_box(
@@ -272,27 +287,38 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                                 (0.001, 0.001, 0.001),
                                 color=(200, 200, 200)
                             )
+                        
                         frames.append(frame)
                         
-                    except Exception as e:
-                        import traceback
+                    except Exception:
                         try:
                             mesh = trimesh.load_mesh(mesh_path)
                             frame = self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
                             if frame is not None:
                                 frames.append(frame)
-                        except Exception as e2:
+                        except Exception:
                             pass
                 
                 return frames[0] if frames else None
                 
-            except Exception as e:
-                import traceback
+            except Exception:
                 mesh = trimesh.load_mesh(mesh_path)
-                return self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
+                if color is None:
+                    return self.viewer.scene.add_mesh_trimesh(name, mesh)
+                else:
+                    return self.viewer.scene.add_mesh_simple(
+                        name, mesh.vertices, mesh.faces,
+                        color=color[:3], opacity=color[3]
+                    )
+        
+        mesh = trimesh.load_mesh(mesh_path)
+        if color is None:
+            return self.viewer.scene.add_mesh_trimesh(name, mesh)
         else:
-            mesh = trimesh.load_mesh(mesh_path)
-            return self.viewer.scene.add_mesh_trimesh(f"{name}", mesh)
+            return self.viewer.scene.add_mesh_simple(
+                name, mesh.vertices, mesh.faces,
+                color=color[:3], opacity=color[3]
+            )
 
     def _add_mesh_from_convex(self, name, geom, color):
         """

From e0bfdf164af6430cb374e356a3655f6db59e9e27 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Fri, 17 Oct 2025 09:42:39 +0200
Subject: [PATCH 10/15] use pathlib instead of os.path and add comments

---
 .../pinocchio/visualize/viser_visualizer.py   | 70 ++++++++++---------
 1 file changed, 37 insertions(+), 33 deletions(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index a60b2b662a..5d56020035 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -8,6 +8,7 @@
 
 import numpy as np
 
+from pathlib import Path
 from trimesh.exchange import dae
 from .. import pinocchio_pywrap_default as pin
 from . import BaseVisualizer
@@ -220,14 +221,17 @@ def loadViewerGeometryObject(self, geometry_object, prefix="", color=None):
 
     def _add_mesh_from_path(self, name, mesh_path, color=None):
         """
-        Load a mesh from a file.
+        Load a mesh from a file
         """
-        ext = os.path.splitext(mesh_path)[1].lower()
-        
+        print("on passe la")
+        mesh_path = Path(mesh_path)
+        ext = mesh_path.suffix.lower()
+
         if ext == ".dae":
             try:
                 mesh_collada = collada.Collada(mesh_path)
                 
+                # If there are more geometries than effects, fall back to trimesh
                 if len(mesh_collada.effects) < len(mesh_collada.geometries):
                     mesh = trimesh.load_mesh(mesh_path)
                     if color is None:
@@ -237,71 +241,69 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                             name, mesh.vertices, mesh.faces,
                             color=color[:3], opacity=color[3]
                         )
-                
+
                 frames = []
-                for i, (geometry, effect) in enumerate(
-                    zip(mesh_collada.geometries, mesh_collada.effects)
-                ):
+                for i, (geometry, effect) in enumerate(zip(mesh_collada.geometries, mesh_collada.effects)):
                     try:
+                        # Extract vertices and indices from Collada geometry
                         vertices = geometry.primitives[0].sources["VERTEX"][0][4].data
                         indices = geometry.primitives[0].indices
-                        
+
+                        # Handle different shapes of indices array
                         if indices.ndim == 3:
                             faces = indices[:, :, 0]
-                        elif indices.ndim == 2:
-                            faces = indices
-                        elif indices.ndim == 1:
+                        elif indices.ndim in (1, 2):
                             faces = indices.reshape(-1, 3)
                         else:
                             faces = indices.reshape(-1, 3)
-                        
-                        if faces.shape[-1] != 3:
-                            if faces.size % 3 == 0:
-                                faces = faces.reshape(-1, 3)
-                        
+
+                        # If after reshaping the last dimension isn't 3, try reshaping again
+                        if faces.shape[-1] != 3 and faces.size % 3 == 0:
+                            faces = faces.reshape(-1, 3)
+
                         mesh_color = getattr(effect, "diffuse", None)
-                        
+
+                        # Add mesh with appropriate color
                         if mesh_color is not None:
                             frame = self.viewer.scene.add_mesh_simple(
-                                f"{name}_{i}",
-                                vertices,
-                                faces,
-                                color=mesh_color[:3],
-                                opacity=mesh_color[3],
+                                f"{name}_{i}", vertices, faces,
+                                color=mesh_color[:3], opacity=mesh_color[3]
                             )
                         elif color is not None:
                             frame = self.viewer.scene.add_mesh_simple(
-                                f"{name}_{i}",
-                                vertices,
-                                faces,
-                                color=color[:3],
-                                opacity=color[3],
+                                f"{name}_{i}", vertices, faces,
+                                color=color[:3], opacity=color[3]
                             )
                         else:
+                            # No color available, fallback to trimesh loader
                             mesh = trimesh.load_mesh(mesh_path)
                             frame = self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
-                        
+
+                        # If for some reason the mesh wasn't added, use a tiny placeholder box
                         if frame is None:
                             frame = self.viewer.scene.add_box(
                                 f"{name}_{i}_placeholder",
                                 (0.001, 0.001, 0.001),
                                 color=(200, 200, 200)
                             )
-                        
+
                         frames.append(frame)
-                        
+
                     except Exception:
+                        # Failed to process this geometry manually, fallback to trimesh
                         try:
                             mesh = trimesh.load_mesh(mesh_path)
                             frame = self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
                             if frame is not None:
                                 frames.append(frame)
                         except Exception:
+                            # Totally failed, skip this geometry
                             pass
-                
+
                 return frames[0] if frames else None
-                
+
             except Exception:
+                # Failed to load as Collada, fallback to trimesh for other formats or malformed .dae
                 mesh = trimesh.load_mesh(mesh_path)
                 if color is None:
                     return self.viewer.scene.add_mesh_trimesh(name, mesh)
@@ -310,7 +312,8 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                         name, mesh.vertices, mesh.faces,
                         color=color[:3], opacity=color[3]
                     )
-        
+
+        # For non-Collada files
         mesh = trimesh.load_mesh(mesh_path)
         if color is None:
             return self.viewer.scene.add_mesh_trimesh(name, mesh)
@@ -320,6 +323,7 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                 color=color[:3], opacity=color[3]
             )
 
+
     def _add_mesh_from_convex(self, name, geom, color):
         """
         Load a mesh from triangles stored inside a hppfcl.Convex.

From bcf16810763111a9b4dfe6e9e9f835bb1e1ef224 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Fri, 17 Oct 2025 09:45:15 +0200
Subject: [PATCH 11/15] restore default robot after testing

---
 examples/gepetto-viewer.py | 4 ++--
 examples/viser-viewer.py   | 5 +++--
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/examples/gepetto-viewer.py b/examples/gepetto-viewer.py
index b996b9b946..95faf6ed3b 100644
--- a/examples/gepetto-viewer.py
+++ b/examples/gepetto-viewer.py
@@ -11,8 +11,8 @@
 # Load the URDF model.
 model_path = Path(os.environ.get("EXAMPLE_ROBOT_DATA_MODEL_DIR"))
 mesh_dir = model_path.parent.parent
-urdf_filename = "panda.urdf"
-urdf_model_path = model_path / "panda_description/urdf" / urdf_filename
+urdf_filename = "talos_reduced.urdf"
+urdf_model_path = model_path / "talos_data/robots" / urdf_filename
 
 model, collision_model, visual_model = pin.buildModelsFromUrdf(
     urdf_model_path, mesh_dir, pin.JointModelFreeFlyer()
diff --git a/examples/viser-viewer.py b/examples/viser-viewer.py
index 33971c6470..b5500ddc19 100644
--- a/examples/viser-viewer.py
+++ b/examples/viser-viewer.py
@@ -17,8 +17,9 @@
 mesh_dir = pinocchio_model_dir
 # urdf_filename = "talos_reduced.urdf"
 # urdf_model_path = join(join(model_path,"talos_data/robots"),urdf_filename)
-urdf_filename = "tiago.urdf"
-urdf_model_path = model_path / "tiago_description/robots" / urdf_filename
+urdf_filename = "solo.urdf"
+urdf_model_path = model_path / "solo_description/robots" / urdf_filename
+
 
 model, collision_model, visual_model = pin.buildModelsFromUrdf(
     urdf_model_path, mesh_dir, pin.JointModelFreeFlyer()

From e98d3282b44554e5217dfe21494173d234cc8b59 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Mon, 20 Oct 2025 08:40:06 +0200
Subject: [PATCH 12/15] remove useless print

---
 bindings/python/pinocchio/visualize/viser_visualizer.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index 5d56020035..8bf2004fe5 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -223,7 +223,6 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
         """
         Load a mesh from a file
         """
-        print("on passe la")
         mesh_path = Path(mesh_path)
         ext = mesh_path.suffix.lower()
 

From 446c65892f7a480f20f8ead2a32af9867c71c3f8 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Mon, 20 Oct 2025 08:44:05 +0200
Subject: [PATCH 13/15] remove extra spaces

---
 examples/viser-viewer.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/examples/viser-viewer.py b/examples/viser-viewer.py
index b5500ddc19..dd4fbe20e1 100644
--- a/examples/viser-viewer.py
+++ b/examples/viser-viewer.py
@@ -20,7 +20,6 @@
 urdf_filename = "solo.urdf"
 urdf_model_path = model_path / "solo_description/robots" / urdf_filename
 
-
 model, collision_model, visual_model = pin.buildModelsFromUrdf(
     urdf_model_path, mesh_dir, pin.JointModelFreeFlyer()
 )

From b8e52741a2fc61e9e47b13ffe5bfcd41f95f0707 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Mon, 20 Oct 2025 09:40:06 +0200
Subject: [PATCH 14/15] simplify face indices normalization logic

---
 bindings/python/pinocchio/visualize/viser_visualizer.py | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index 8bf2004fe5..943d812954 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -251,15 +251,10 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                         # Handle different shapes of indices array
                         if indices.ndim == 3:
                             faces = indices[:, :, 0]
-                        elif indices.ndim in (1, 2):
-                            faces = indices.reshape(-1, 3)
                         else:
                             faces = indices.reshape(-1, 3)
 
-                        # If after reshaping the last dimension isn't 3, try reshaping again
-                        if faces.shape[-1] != 3 and faces.size % 3 == 0:
-                            faces = faces.reshape(-1, 3)
-
+                        # Extract color from effect or use provided color
                         mesh_color = getattr(effect, "diffuse", None)
 
                         # Add mesh with appropriate color

From ea7a8810db5170f70cd7446136696f54e6553ed8 Mon Sep 17 00:00:00 2001
From: Alexy Legrand <alexy.legrand@laas.fr>
Date: Tue, 21 Oct 2025 09:29:54 +0200
Subject: [PATCH 15/15] add helper function to make the code more
 understandable

---
 .../pinocchio/visualize/viser_visualizer.py   | 155 ++++++++----------
 1 file changed, 71 insertions(+), 84 deletions(-)

diff --git a/bindings/python/pinocchio/visualize/viser_visualizer.py b/bindings/python/pinocchio/visualize/viser_visualizer.py
index 943d812954..50d0543599 100644
--- a/bindings/python/pinocchio/visualize/viser_visualizer.py
+++ b/bindings/python/pinocchio/visualize/viser_visualizer.py
@@ -221,93 +221,81 @@ def loadViewerGeometryObject(self, geometry_object, prefix="", color=None):
 
     def _add_mesh_from_path(self, name, mesh_path, color=None):
         """
-        Load a mesh from a file
+        Load a mesh from a file.
         """
-        mesh_path = Path(mesh_path)
-        ext = mesh_path.suffix.lower()
-
+        ext = os.path.splitext(mesh_path)[1].lower()
+        
         if ext == ".dae":
-            try:
-                mesh_collada = collada.Collada(mesh_path)
-                
-                # If there are more geometries than effects, fall back to trimesh
-                if len(mesh_collada.effects) < len(mesh_collada.geometries):
-                    mesh = trimesh.load_mesh(mesh_path)
-                    if color is None:
-                        return self.viewer.scene.add_mesh_trimesh(name, mesh)
-                    else:
-                        return self.viewer.scene.add_mesh_simple(
-                            name, mesh.vertices, mesh.faces,
-                            color=color[:3], opacity=color[3]
-                        )
-
-                frames = []
-                for i, (geometry, effect) in enumerate(zip(mesh_collada.geometries, mesh_collada.effects)):
-                    try:
-                        # Extract vertices and indices from Collada geometry
-                        vertices = geometry.primitives[0].sources["VERTEX"][0][4].data
-                        indices = geometry.primitives[0].indices
-
-                        # Handle different shapes of indices array
-                        if indices.ndim == 3:
-                            faces = indices[:, :, 0]
-                        else:
-                            faces = indices.reshape(-1, 3)
-
-                        # Extract color from effect or use provided color
-                        mesh_color = getattr(effect, "diffuse", None)
-
-                        # Add mesh with appropriate color
-                        if mesh_color is not None:
-                            frame = self.viewer.scene.add_mesh_simple(
-                                f"{name}_{i}", vertices, faces,
-                                color=mesh_color[:3], opacity=mesh_color[3]
-                            )
-                        elif color is not None:
-                            frame = self.viewer.scene.add_mesh_simple(
-                                f"{name}_{i}", vertices, faces,
-                                color=color[:3], opacity=color[3]
-                            )
-                        else:
-                            # No color available, fallback to trimesh loader
-                            mesh = trimesh.load_mesh(mesh_path)
-                            frame = self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
-
-                        # If for some reason the mesh wasn't added, use a tiny placeholder box
-                        if frame is None:
-                            frame = self.viewer.scene.add_box(
-                                f"{name}_{i}_placeholder",
-                                (0.001, 0.001, 0.001),
-                                color=(200, 200, 200)
-                            )
-
-                        frames.append(frame)
-
-                    except Exception:
-                        # Failed to process this geometry manually, fallback to trimesh
-                        try:
-                            mesh = trimesh.load_mesh(mesh_path)
-                            frame = self.viewer.scene.add_mesh_trimesh(f"{name}_{i}", mesh)
-                            if frame is not None:
-                                frames.append(frame)
-                        except Exception:
-                            # Totally failed, skip this geometry
-                            pass
-
-                return frames[0] if frames else None
+            return self._load_collada_mesh(name, mesh_path, color)
+        else:
+            return self._load_standard_mesh(name, mesh_path, color)
 
-            except Exception:
-                # Failed to load as Collada, fallback to trimesh for other formats or malformed .dae
+    def _load_collada_mesh(self, name, mesh_path, color):
+        """
+        Load a COLLADA mesh with color support.
+        """
+        try:
+            mesh_collada = collada.Collada(mesh_path)
+            
+            if len(mesh_collada.effects) < len(mesh_collada.geometries):
+                return self._load_standard_mesh(name, mesh_path, color)
+            
+            frames = []
+            for i, (geometry, effect) in enumerate(zip(mesh_collada.geometries, mesh_collada.effects)):
+                frame = self._process_collada_geometry(name, i, geometry, effect, color, mesh_path)
+                if frame:
+                    frames.append(frame)
+            
+            return frames[0] if frames else None
+        except Exception:
+            return self._load_standard_mesh(name, mesh_path, color)
+
+    def _process_collada_geometry(self, name, index, geometry, effect, fallback_color, mesh_path):
+        """
+        Process a single COLLADA geometry with its material.
+        """
+        try:
+            vertices, faces = self._extract_geometry_data(geometry)
+            mesh_color = getattr(effect, "diffuse", None)
+            
+            if mesh_color is not None:
+                return self.viewer.scene.add_mesh_simple(
+                    f"{name}_{index}", vertices, faces,
+                    color=mesh_color[:3], opacity=mesh_color[3]
+                )
+            elif fallback_color is not None:
+                return self.viewer.scene.add_mesh_simple(
+                    f"{name}_{index}", vertices, faces,
+                    color=fallback_color[:3], opacity=fallback_color[3]
+                )
+            else:
                 mesh = trimesh.load_mesh(mesh_path)
-                if color is None:
-                    return self.viewer.scene.add_mesh_trimesh(name, mesh)
-                else:
-                    return self.viewer.scene.add_mesh_simple(
-                        name, mesh.vertices, mesh.faces,
-                        color=color[:3], opacity=color[3]
-                    )
-
-        # For non-Collada files
+                return self.viewer.scene.add_mesh_trimesh(f"{name}_{index}", mesh)
+        except Exception:
+            try:
+                mesh = trimesh.load_mesh(mesh_path)
+                return self.viewer.scene.add_mesh_trimesh(f"{name}_{index}", mesh)
+            except Exception:
+                return None
+
+    def _extract_geometry_data(self, geometry):
+        """
+        Extract vertices and faces from a COLLADA geometry.
+        """
+        vertices = geometry.primitives[0].sources["VERTEX"][0][4].data
+        indices = geometry.primitives[0].indices
+        
+        if indices.ndim == 3:
+            faces = indices[:, :, 0]
+        else:
+            faces = indices.reshape(-1, 3)
+        
+        return vertices, faces
+
+    def _load_standard_mesh(self, name, mesh_path, color):
+        """
+        Load a mesh using trimesh (STL and other formats).
+        """
         mesh = trimesh.load_mesh(mesh_path)
         if color is None:
             return self.viewer.scene.add_mesh_trimesh(name, mesh)
@@ -317,7 +305,6 @@ def _add_mesh_from_path(self, name, mesh_path, color=None):
                 color=color[:3], opacity=color[3]
             )
 
-
     def _add_mesh_from_convex(self, name, geom, color):
         """
         Load a mesh from triangles stored inside a hppfcl.Convex.