Remove Drawable abstraction.

Instead, use a set of functions to create/update a Renderable
from an mjvGeom.

This completely isolates mjvScene/mjvGeom from SceneView,
making SceneView a more general purpose class.

PiperOrigin-RevId: 899475268
Change-Id: I48a3a45bc8fff3e1f514847c7a1ca8ab3a1ff16e

src/experimental/filament/CMakeLists.txt

@@ -27,8 +27,6 @@ target_sources(${MUJOCO_FILAMENT_TARGET_NAME}
         filament/builtins.h
         filament/color_grading_options.cc
         filament/color_grading_options.h
-        filament/drawable.cc
-        filament/drawable.h
         filament/filament_context.cc
         filament/filament_context.h
         filament/filament_platform_factory.cc
@@ -56,6 +54,8 @@ target_sources(${MUJOCO_FILAMENT_TARGET_NAME}
         filament/renderable.h
         filament/scene_bridge.cc
         filament/scene_bridge.h
+        filament/scene_geom_util.cc
+        filament/scene_geom_util.h
         filament/scene_view.cc
         filament/scene_view.h
         filament/texture.cc

src/experimental/filament/filament/drawable.h

@@ -1,70 +0,0 @@
-// Copyright 2025 DeepMind Technologies Limited
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef MUJOCO_SRC_EXPERIMENTAL_FILAMENT_FILAMENT_DRAWABLE_H_
-#define MUJOCO_SRC_EXPERIMENTAL_FILAMENT_FILAMENT_DRAWABLE_H_
-
-#include <math/mat4.h>
-#include <mujoco/mjmodel.h>
-#include <mujoco/mjtnum.h>
-#include <mujoco/mjvisualize.h>
-#include "experimental/filament/filament/material.h"
-#include "experimental/filament/filament/model_objects.h"
-#include "experimental/filament/filament/object_manager.h"
-#include "experimental/filament/filament/renderable.h"
-
-namespace mujoco {
-
-// Manages the filament Entities and MaterialInstances for a single mjvGeom.
-class Drawable {
- public:
-  Drawable(ModelObjects* model_objects, const mjvScene* scene,
-           const mjvGeom& geom);
-  ~Drawable() noexcept = default;
-
-  Drawable(const Drawable&) = delete;
-  Drawable& operator=(const Drawable&) = delete;
-
-  // Updates the transform of the drawable for rendering.
-  void SetTransform(const mjvGeom& geom);
-
-  // Updates the material parameters of the drawable for rendering.
-  void UpdateMaterial(const mjModel* model, const mjvGeom& geom,
-                      ModelObjects* model_objs, const float headpos[3],
-                      const mjtByte render_flags[mjNRNDFLAG],
-                      ObjectManager::MaterialType* out_material_type);
-
-  // Returns the transform of the drawable.
-  const filament::math::mat4& GetTransform() const { return transform_; }
-
-  // Returns the renderable for the drawable.
-  Renderable& GetRenderable() { return renderable_; }
-
-  // Returns the material for the drawable.
-  Material& GetMaterial() { return renderable_.GetMaterial(); }
-
- private:
-  void AddMesh(ModelObjects* model_objs, int data_id);
-  void AddGeom(ModelObjects* model_objs, const mjvScene* scene,
-               const mjvGeom& geom);
-  void AddHeightField(ModelObjects* model_objs, int hfield_id);
-  void AddShape(ModelObjects* model_objs, ModelObjects::ShapeType shape_type);
-
-  Renderable renderable_;
-  filament::math::mat4 transform_;
-};
-
-}  // namespace mujoco
-
-#endif  // MUJOCO_SRC_EXPERIMENTAL_FILAMENT_FILAMENT_DRAWABLE_H_

src/experimental/filament/filament/scene_bridge.cc

@@ -29,7 +29,6 @@
 #include <filament/RenderTarget.h>
 #include <filament/Skybox.h>
 #include <filament/View.h>
-#include <filament/Viewport.h>
 #include <math/TMatHelpers.h>
 #include <math/mat4.h>
 #include <math/mathfwd.h>
@@ -38,7 +37,6 @@
 #include <math/TVecHelpers.h>
 #include <mujoco/mujoco.h>
 #include "experimental/filament/filament/color_grading_options.h"
-#include "experimental/filament/filament/drawable.h"
 #include "experimental/filament/filament/gui_view.h"
 #include "experimental/filament/filament/light.h"
 #include "experimental/filament/filament/material.h"
@@ -46,6 +44,8 @@
 #include "experimental/filament/filament/model_objects.h"
 #include "experimental/filament/filament/model_util.h"
 #include "experimental/filament/filament/object_manager.h"
+#include "experimental/filament/filament/renderable.h"
+#include "experimental/filament/filament/scene_geom_util.h"
 #include "experimental/filament/filament/scene_view.h"
 
 namespace mujoco {
@@ -164,10 +164,10 @@ SceneBridge::~SceneBridge() {
   }
   lights_.clear();
 
-  for (auto& iter : drawables_) {
+  for (auto& iter : renderables_) {
     scene_view_->RemoveFromScene(iter.get());
   }
-  drawables_.clear();
+  renderables_.clear();
 }
 
 void SceneBridge::SetEnvironmentLight(std::string_view filename,
@@ -305,16 +305,15 @@ void SceneBridge::Update(const mjrRect& viewport, const mjvScene* scene) {
   mju_n2f(headpos, hpos, 3);
   mju_n2f(gazedir, hfwd, 3);
 
-  const mjModel* model = model_objects_->GetModel();
   const mjvGLCamera gl_camera =
       mjv_averageCamera(scene->camera, scene->camera + 1);
   clip_from_world_ = CalculateClipFromWorld(viewport, gl_camera);
 
   // Remove all drawables from previous render and prepare new ones.
-  for (auto& iter : drawables_) {
+  for (auto& iter : renderables_) {
     scene_view_->RemoveFromScene(iter.get());
   }
-  drawables_.clear();
+  renderables_.clear();
   for (int i = 0; i < scene->ngeom; ++i) {
     const mjvGeom* geom = scene->geoms + i;
 
@@ -324,28 +323,12 @@ void SceneBridge::Update(const mjrRect& viewport, const mjvScene* scene) {
       }
     }
 
-    auto drawable =
-        std::make_unique<Drawable>(model_objects_.get(), scene, *geom);
-    drawable->SetTransform(*geom);
+    std::unique_ptr<Renderable> renderable =
+        CreateGeomRenderable(*geom, scene, object_mgr_, model_objects_.get(),
+                             headpos, &fallback_textures_);
 
-    ObjectManager::MaterialType material_type = ObjectManager::kNumMaterials;
-    drawable->UpdateMaterial(model, *geom, model_objects_.get(), headpos,
-                             scene->flags, &material_type);
-
-    Material& material = drawable->GetMaterial();
-    material.SetFallbackTextures(&fallback_textures_);
-    material.SetMaterial(
-        Material::DrawMode::kNormal,
-        object_mgr_->GetMaterial(material_type));
-    material.SetMaterial(
-        Material::DrawMode::kDepth,
-        object_mgr_->GetMaterial(ObjectManager::kUnlitDepth));
-    material.SetMaterial(
-        Material::DrawMode::kSegmentation,
-        object_mgr_->GetMaterial(ObjectManager::kUnlitSegmentation));
-
-    scene_view_->AddToScene(drawable.get());
-    drawables_.push_back(std::move(drawable));
+    scene_view_->AddToScene(renderable.get());
+    renderables_.push_back(std::move(renderable));
   }
 
   bool headlight_enabled = false;

src/experimental/filament/filament/scene_bridge.h

@@ -24,11 +24,11 @@
 #include <math/vec3.h>
 #include <mujoco/mjvisualize.h>
 #include <mujoco/mujoco.h>
-#include "experimental/filament/filament/drawable.h"
 #include "experimental/filament/filament/light.h"
 #include "experimental/filament/filament/material.h"
 #include "experimental/filament/filament/model_objects.h"
 #include "experimental/filament/filament/object_manager.h"
+#include "experimental/filament/filament/renderable.h"
 #include "experimental/filament/filament/scene_view.h"
 
 namespace mujoco {
@@ -72,7 +72,7 @@ class SceneBridge {
   ObjectManager* object_mgr_ = nullptr;
   std::unique_ptr<ModelObjects> model_objects_;
   std::vector<std::unique_ptr<Light>> lights_;
-  std::vector<std::unique_ptr<Drawable>> drawables_;
+  std::vector<std::unique_ptr<Renderable>> renderables_;
   filament::math::mat4 clip_from_world_;
   int default_shadow_map_size_ = 2048;
   float default_vsm_blur_width_ = 0.0f;

src/experimental/filament/filament/scene_geom_util.cc

@@ -12,10 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "experimental/filament/filament/drawable.h"
+#include "experimental/filament/filament/scene_geom_util.h"
 
 #include <cmath>
 #include <cstdint>
+#include <memory>
 #include <numbers>
 
 #include <filament/Material.h>
@@ -81,80 +82,111 @@ static float GetPlaneTileSize(const mjModel* model, int matid,
 }
 
 static bool IsBehind(const float* headpos, const float* pos, const float* mat) {
-  return ((headpos[0] - pos[0]) * mat[2] +
-          (headpos[1] - pos[1]) * mat[5] +
-          (headpos[2] - pos[2]) * mat[8] < 0.0f);
+  return ((headpos[0] - pos[0]) * mat[2] + (headpos[1] - pos[1]) * mat[5] +
+              (headpos[2] - pos[2]) * mat[8] <
+          0.0f);
 }
 
-Drawable::Drawable(ModelObjects* model_objects, const mjvScene* scene,
-                   const mjvGeom& geom)
-    : renderable_(model_objects->GetEngine()) {
-  if (geom.category == mjCAT_DECOR) {
-    renderable_.SetCastShadows(false);
-    renderable_.SetReceiveShadows(false);
+static void AddMesh(Renderable& renderable, ModelObjects* model_objs,
+                    int data_id) {
+  const Mesh* mesh = model_objs->GetMeshBuffer(data_id);
+  if (mesh == nullptr) {
+    mju_error("Unknown mesh %d", data_id);
   }
+  renderable.Append(mesh);
+}
 
+static void AddGeom(Renderable& renderable, ModelObjects* model_objs,
+                    const mjvScene* scene, const mjvGeom& geom) {
+  if (geom.type == mjGEOM_FLEX) {
+    renderable.Append(model_objs->CreateFlexMesh(scene, geom));
+  } else if (geom.type == mjGEOM_SKIN) {
+    renderable.Append(model_objs->CreateSkinMesh(scene, geom));
+  }
+}
+
+static void AddHeightField(Renderable& renderable, ModelObjects* model_objs,
+                           int hfield_id) {
+  const Mesh* mesh = model_objs->GetHeightFieldBuffer(hfield_id);
+  if (mesh == nullptr) {
+    mju_error("Unknown height field %d", hfield_id);
+  }
+  renderable.Append(mesh);
+}
+
+static void AddShape(Renderable& renderable, ModelObjects* model_objs,
+                     ModelObjects::ShapeType shape_type) {
+  const Mesh* mesh = model_objs->GetShapeBuffer(shape_type);
+  if (mesh == nullptr) {
+    mju_error("Unknown shape %d", shape_type);
+  }
+  renderable.Append(mesh);
+}
+
+static void PrepareGeomMeshes(Renderable& renderable, const mjvGeom& geom,
+                              const mjvScene* scene,
+                              ModelObjects* model_objects) {
   switch ((mjtGeom)geom.type) {
     case mjGEOM_MESH:
-      AddMesh(model_objects, geom.dataid);
+      AddMesh(renderable, model_objects, geom.dataid);
       break;
     case mjGEOM_HFIELD:
-      AddHeightField(model_objects, geom.dataid);
+      AddHeightField(renderable, model_objects, geom.dataid);
       break;
     case mjGEOM_PLANE:
-      AddShape(model_objects, ModelObjects::kPlane);
+      AddShape(renderable, model_objects, ModelObjects::kPlane);
       break;
     case mjGEOM_SPHERE:
-      AddShape(model_objects, ModelObjects::kSphere);
+      AddShape(renderable, model_objects, ModelObjects::kSphere);
       break;
     case mjGEOM_ELLIPSOID:
-      AddShape(model_objects, ModelObjects::kSphere);
+      AddShape(renderable, model_objects, ModelObjects::kSphere);
       break;
     case mjGEOM_BOX:
-      AddShape(model_objects, ModelObjects::kBox);
+      AddShape(renderable, model_objects, ModelObjects::kBox);
       break;
     case mjGEOM_CAPSULE:
-      AddShape(model_objects, ModelObjects::kTube);
-      AddShape(model_objects, ModelObjects::kDome);
-      AddShape(model_objects, ModelObjects::kDome);
+      AddShape(renderable, model_objects, ModelObjects::kTube);
+      AddShape(renderable, model_objects, ModelObjects::kDome);
+      AddShape(renderable, model_objects, ModelObjects::kDome);
       break;
     case mjGEOM_CYLINDER:
-      AddShape(model_objects, ModelObjects::kTube);
-      AddShape(model_objects, ModelObjects::kDisk);
-      AddShape(model_objects, ModelObjects::kDisk);
+      AddShape(renderable, model_objects, ModelObjects::kTube);
+      AddShape(renderable, model_objects, ModelObjects::kDisk);
+      AddShape(renderable, model_objects, ModelObjects::kDisk);
       break;
     case mjGEOM_ARROW:
-      AddShape(model_objects, ModelObjects::kTube);
-      AddShape(model_objects, ModelObjects::kCone);
-      AddShape(model_objects, ModelObjects::kDisk);
+      AddShape(renderable, model_objects, ModelObjects::kTube);
+      AddShape(renderable, model_objects, ModelObjects::kCone);
+      AddShape(renderable, model_objects, ModelObjects::kDisk);
       break;
     case mjGEOM_ARROW1:
-      AddShape(model_objects, ModelObjects::kTube);
-      AddShape(model_objects, ModelObjects::kCone);
-      AddShape(model_objects, ModelObjects::kDisk);
-      AddShape(model_objects, ModelObjects::kDisk);
+      AddShape(renderable, model_objects, ModelObjects::kTube);
+      AddShape(renderable, model_objects, ModelObjects::kCone);
+      AddShape(renderable, model_objects, ModelObjects::kDisk);
+      AddShape(renderable, model_objects, ModelObjects::kDisk);
       break;
     case mjGEOM_ARROW2:
-      AddShape(model_objects, ModelObjects::kTube);
-      AddShape(model_objects, ModelObjects::kCone);
-      AddShape(model_objects, ModelObjects::kCone);
-      AddShape(model_objects, ModelObjects::kDisk);
-      AddShape(model_objects, ModelObjects::kDisk);
+      AddShape(renderable, model_objects, ModelObjects::kTube);
+      AddShape(renderable, model_objects, ModelObjects::kCone);
+      AddShape(renderable, model_objects, ModelObjects::kCone);
+      AddShape(renderable, model_objects, ModelObjects::kDisk);
+      AddShape(renderable, model_objects, ModelObjects::kDisk);
       break;
     case mjGEOM_LINE:
-      AddShape(model_objects, ModelObjects::kLine);
+      AddShape(renderable, model_objects, ModelObjects::kLine);
       break;
     case mjGEOM_LINEBOX:
-      AddShape(model_objects, ModelObjects::kLineBox);
+      AddShape(renderable, model_objects, ModelObjects::kLineBox);
       break;
     case mjGEOM_TRIANGLE:
-      AddShape(model_objects, ModelObjects::kTriangle);
+      AddShape(renderable, model_objects, ModelObjects::kTriangle);
       break;
     case mjGEOM_FLEX:
-      AddGeom(model_objects, scene, geom);
+      AddGeom(renderable, model_objects, scene, geom);
       break;
     case mjGEOM_SKIN:
-      AddGeom(model_objects, scene, geom);
+      AddGeom(renderable, model_objects, scene, geom);
       break;
     case mjGEOM_NONE:
     case mjGEOM_LABEL:
@@ -167,56 +199,22 @@ Drawable::Drawable(ModelObjects* model_objects, const mjvScene* scene,
   }
 }
 
-void Drawable::AddMesh(ModelObjects* model_objs, int data_id) {
-  const Mesh* mesh = model_objs->GetMeshBuffer(data_id);
-  if (mesh == nullptr) {
-    mju_error("Unknown mesh %d", data_id);
-  }
-  renderable_.Append(mesh);
-}
-
-void Drawable::AddGeom(ModelObjects* model_objs, const mjvScene* scene,
-                       const mjvGeom& geom) {
-  if (geom.type == mjGEOM_FLEX) {
-    renderable_.Append(model_objs->CreateFlexMesh(scene, geom));
-  } else if (geom.type == mjGEOM_SKIN) {
-    renderable_.Append(model_objs->CreateSkinMesh(scene, geom));
-  }
-}
-
-void Drawable::AddHeightField(ModelObjects* model_objs, int hfield_id) {
-  const Mesh* mesh = model_objs->GetHeightFieldBuffer(hfield_id);
-  if (mesh == nullptr) {
-    mju_error("Unknown height field %d", hfield_id);
-  }
-  renderable_.Append(mesh);
-}
-
-void Drawable::AddShape(ModelObjects* model_objs,
-                        ModelObjects::ShapeType shape_type) {
-  const Mesh* mesh = model_objs->GetShapeBuffer(shape_type);
-  if (mesh == nullptr) {
-    mju_error("Unknown shape %d", shape_type);
-  }
-  renderable_.Append(mesh);
-}
-
-void Drawable::SetTransform(const mjvGeom& geom) {
+static void SetGeomTransform(Renderable& renderable, const mjvGeom& geom) {
   // Flex and skin geometries are in global space.
   if (geom.type == mjGEOM_FLEX || geom.type == mjGEOM_SKIN) {
     return;
   }
 
-  transform_ = mat4(ReadMat3(geom.mat), ReadFloat3(geom.pos));
+  mat4 transform = mat4(ReadMat3(geom.mat), ReadFloat3(geom.pos));
 
   float3 size = ReadFloat3(geom.size);
   filament::TransformManager& tm =
-      renderable_.GetEngine()->getTransformManager();
-  for (int j = 0; j < renderable_.GetNumEntities(); ++j) {
-    const utils::Entity& entity = renderable_[j];
+      renderable.GetEngine()->getTransformManager();
+  for (int j = 0; j < renderable.GetNumEntities(); ++j) {
+    const utils::Entity& entity = renderable[j];
 
     // Update object transform.
-    mat4 entity_transform = transform_;
+    mat4 entity_transform = transform;
 
     // Some built-in drawables are composed of multiple entities. For example,
     // capsules are a combination of a open tube and two dome end caps.
@@ -318,27 +316,34 @@ void Drawable::SetTransform(const mjvGeom& geom) {
   }
 }
 
-void Drawable::UpdateMaterial(const mjModel* model, const mjvGeom& geom,
-                              ModelObjects* model_objs, const float headpos[3],
-                              const mjtByte render_flags[mjNRNDFLAG],
-                              ObjectManager::MaterialType* out_material_type) {
-  const bool use_segid_color = render_flags[mjRND_IDCOLOR];
-  const bool enable_reflection = render_flags[mjRND_REFLECTION];
+static void UpdateGeomMaterial(Renderable& renderable, const mjvGeom& geom,
+                               const mjvScene* scene, ModelObjects* model_objs,
+                               ObjectManager* object_mgr,
+                               const float headpos[3]) {
+  const mjModel* model = model_objs->GetModel();
+  Material& material = renderable.GetMaterial();
+
+  const bool use_segid_color = scene->flags[mjRND_IDCOLOR];
+  const bool enable_reflection = scene->flags[mjRND_REFLECTION];
 
   Material::Params params;
   params.color = ReadFloat4(geom.rgba);
   if (geom.type == mjGEOM_PLANE) {
     if (IsBehind(headpos, geom.pos, geom.mat)) {
       params.color[3] *= 0.3;
-      renderable_.SetReceiveShadows(false);
+      renderable.SetReceiveShadows(false);
       params.reflective = false;
     } else {
-      renderable_.SetReceiveShadows(true);
+      renderable.SetReceiveShadows(true);
       params.reflective =
           enable_reflection && geom.reflectance > 0 && params.color.a == 1.0f;
     }
   }
-  renderable_.SetWireframe(render_flags[mjRND_WIREFRAME]);
+  renderable.SetWireframe(scene->flags[mjRND_WIREFRAME]);
+  if (geom.category == mjCAT_DECOR) {
+    renderable.SetCastShadows(false);
+    renderable.SetReceiveShadows(false);
+  }
 
   Material::Textures textures;
   if (geom.matid >= 0) {
@@ -351,25 +356,26 @@ void Drawable::UpdateMaterial(const mjModel* model, const mjvGeom& geom,
         model_objs->GetTexture(geom.matid, mjTEXROLE_ROUGHNESS);
     textures.occlusion =
         model_objs->GetTexture(geom.matid, mjTEXROLE_OCCLUSION);
-    GetMaterial().UpdateTextures(textures);
+    material.UpdateTextures(textures);
   }
 
+  ObjectManager::MaterialType material_type = ObjectManager::kNumMaterials;
   if (geom.type == mjGEOM_LINE || geom.type == mjGEOM_LINEBOX) {
-    *out_material_type = ObjectManager::kUnlitLine;
+    material_type = ObjectManager::kUnlitLine;
   } else {
     bool material_assigned = false;
     if (geom.matid >= 0) {
       material_assigned = true;
       if (textures.orm) {
-        *out_material_type = ObjectManager::kPbrPacked;
+        material_type = ObjectManager::kPbrPacked;
       } else if (textures.metallic) {
-        *out_material_type = ObjectManager::kPbr;
+        material_type = ObjectManager::kPbr;
       } else if (textures.roughness) {
-        *out_material_type = ObjectManager::kPbr;
+        material_type = ObjectManager::kPbr;
       } else if (model->mat_metallic[geom.matid] >= 0) {
-        *out_material_type = ObjectManager::kPbr;
+        material_type = ObjectManager::kPbr;
       } else if (model->mat_roughness[geom.matid] >= 0) {
-        *out_material_type = ObjectManager::kPbr;
+        material_type = ObjectManager::kPbr;
       } else {
         material_assigned = false;
       }
@@ -388,36 +394,36 @@ void Drawable::UpdateMaterial(const mjModel* model, const mjvGeom& geom,
 
       if (textures.color == nullptr) {
         if (params.color.a < 1.0f) {
-          *out_material_type = ObjectManager::kPhongColorFade;
+          material_type = ObjectManager::kPhongColorFade;
         } else if (params.reflective) {
-          *out_material_type = ObjectManager::kPhongColorReflect;
+          material_type = ObjectManager::kPhongColorReflect;
         } else {
-          *out_material_type = ObjectManager::kPhongColor;
+          material_type = ObjectManager::kPhongColor;
         }
       } else if (textures.color->GetFilamentTexture()->getTarget() ==
-                filament::Texture::Sampler::SAMPLER_CUBEMAP) {
+                 filament::Texture::Sampler::SAMPLER_CUBEMAP) {
         if (params.color.a < 1.0f) {
-          *out_material_type = ObjectManager::kPhongCubeFade;
+          material_type = ObjectManager::kPhongCubeFade;
         } else if (params.reflective) {
-          *out_material_type = ObjectManager::kPhongCubeReflect;
+          material_type = ObjectManager::kPhongCubeReflect;
         } else {
-          *out_material_type = ObjectManager::kPhongCube;
+          material_type = ObjectManager::kPhongCube;
         }
       } else if (has_texcoords) {
         if (params.color.a < 1.0f) {
-          *out_material_type = ObjectManager::kPhong2dUvFade;
+          material_type = ObjectManager::kPhong2dUvFade;
         } else if (params.reflective) {
-          *out_material_type = ObjectManager::kPhong2dUvReflect;
+          material_type = ObjectManager::kPhong2dUvReflect;
         } else {
-          *out_material_type = ObjectManager::kPhong2dUv;
+          material_type = ObjectManager::kPhong2dUv;
         }
       } else {
         if (params.color.a < 1.0f) {
-          *out_material_type = ObjectManager::kPhong2dFade;
+          material_type = ObjectManager::kPhong2dFade;
         } else if (params.reflective) {
-          *out_material_type = ObjectManager::kPhong2dReflect;
+          material_type = ObjectManager::kPhong2dReflect;
         } else {
-          *out_material_type = ObjectManager::kPhong2d;
+          material_type = ObjectManager::kPhong2d;
         }
       }
     }
@@ -522,7 +528,32 @@ void Drawable::UpdateMaterial(const mjModel* model, const mjvGeom& geom,
   params.emissive *= model_objs->GetEmissiveMultiplier();
   params.specular *= model_objs->GetSpecularMultiplier();
   params.glossiness *= model_objs->GetShininessMultiplier();
+  material.UpdateParams(params);
 
-  GetMaterial().UpdateParams(params);
+  material.SetMaterial(
+      Material::DrawMode::kNormal,
+      object_mgr->GetMaterial(material_type));
+  material.SetMaterial(
+      Material::DrawMode::kDepth,
+      object_mgr->GetMaterial(ObjectManager::kUnlitDepth));
+  material.SetMaterial(
+      Material::DrawMode::kSegmentation,
+      object_mgr->GetMaterial(ObjectManager::kUnlitSegmentation));
+}
+
+std::unique_ptr<Renderable> CreateGeomRenderable(
+    const mjvGeom& geom, const mjvScene* scene, ObjectManager* object_mgr,
+    ModelObjects* model_objs, const float headpos[3],
+    Material::Textures* fallback_textures) {
+  auto renderable = std::make_unique<Renderable>(model_objs->GetEngine());
+
+  // The order of these calls is important. e.g. We need to create the filament
+  // renderable entities before we can set their transform.
+  PrepareGeomMeshes(*renderable, geom, scene, model_objs);
+  SetGeomTransform(*renderable, geom);
+  renderable->GetMaterial().SetFallbackTextures(fallback_textures);
+  UpdateGeomMaterial(*renderable, geom, scene, model_objs, object_mgr, headpos);
+
+  return renderable;
 }
 }  // namespace mujoco

src/experimental/filament/filament/scene_geom_util.h

@@ -0,0 +1,36 @@
+// Copyright 2025 DeepMind Technologies Limited
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef MUJOCO_SRC_EXPERIMENTAL_FILAMENT_FILAMENT_SCENE_GEOM_UTIL_H_
+#define MUJOCO_SRC_EXPERIMENTAL_FILAMENT_FILAMENT_SCENE_GEOM_UTIL_H_
+
+#include <memory>
+
+#include <mujoco/mjvisualize.h>
+#include "experimental/filament/filament/material.h"
+#include "experimental/filament/filament/model_objects.h"
+#include "experimental/filament/filament/object_manager.h"
+#include "experimental/filament/filament/renderable.h"
+
+namespace mujoco {
+
+// Creates a Renderable from the given mjvGeom.
+std::unique_ptr<Renderable> CreateGeomRenderable(
+    const mjvGeom& geom, const mjvScene* scene, ObjectManager* object_mgr,
+    ModelObjects* model_objs, const float headpos[3],
+    Material::Textures* fallback_textures);
+
+}  // namespace mujoco
+
+#endif  // MUJOCO_SRC_EXPERIMENTAL_FILAMENT_FILAMENT_SCENE_GEOM_UTIL_H_

src/experimental/filament/filament/scene_view.cc

@@ -40,7 +40,6 @@
 #include <utils/EntityManager.h>
 #include <mujoco/mujoco.h>
 #include "experimental/filament/filament/color_grading_options.h"
-#include "experimental/filament/filament/drawable.h"
 #include "experimental/filament/filament/light.h"
 #include "experimental/filament/filament/material.h"
 #include "experimental/filament/filament/math_util.h"
@@ -162,11 +161,11 @@ SceneView::~SceneView() {
   for (auto& light : lights_) {
     light->RemoveFromScene(scene_);
   }
-  for (auto& drawable : drawables_) {
-    drawable->GetRenderable().RemoveFromScene(scene_);
+  for (auto& renderable : renderables_) {
+    renderable->RemoveFromScene(scene_);
   }
   lights_.clear();
-  drawables_.clear();
+  renderables_.clear();
   reflect_targets_.clear();
   engine_->destroyCameraComponent(reflect_camera_->getEntity());
   engine_->destroy(reflect_view_);
@@ -192,22 +191,22 @@ void SceneView::RemoveFromScene(Light* light) {
   }
 }
 
-void SceneView::AddToScene(Drawable* drawable) {
-  if (drawables_.insert(drawable).second) {
-    drawable->GetRenderable().AddToScene(scene_);
-    if (drawable->GetMaterial().GetParams().reflective) {
-      AddReflectiveDrawable(drawable);
+void SceneView::AddToScene(Renderable* renderable) {
+  if (renderables_.insert(renderable).second) {
+    renderable->AddToScene(scene_);
+    if (renderable->GetMaterial().GetParams().reflective) {
+      AddReflectiveRenderable(renderable);
     }
   }
 }
 
-void SceneView::RemoveFromScene(Drawable* drawable) {
-  if (drawables_.erase(drawable)) {
-    auto it = std::find(reflectives_.begin(), reflectives_.end(), drawable);
+void SceneView::RemoveFromScene(Renderable* renderable) {
+  if (renderables_.erase(renderable)) {
+    auto it = std::find(reflectives_.begin(), reflectives_.end(), renderable);
     if (it != reflectives_.end()) {
       reflectives_.erase(it);
     }
-    drawable->GetRenderable().RemoveFromScene(scene_);
+    renderable->RemoveFromScene(scene_);
   }
 }
 
@@ -246,11 +245,9 @@ void SceneView::Render(filament::Renderer* renderer,
 
   SetupCamera(request.camera, viewport, camera_);
 
-  for (auto& iter : drawables_) {
+  for (auto& iter : renderables_) {
     Material& material = iter->GetMaterial();
-    Renderable& renderable = iter->GetRenderable();
-    renderable.SetMaterialInstance(
-        material.GetMaterialInstance(request.draw_mode));
+    iter->SetMaterialInstance(material.GetMaterialInstance(request.draw_mode));
   }
 
   filament::View* view = views_[static_cast<int>(request.draw_mode)];
@@ -266,13 +263,17 @@ void SceneView::Render(filament::Renderer* renderer,
 
   // Render reflection passes.
   if (request.draw_mode == DrawMode::kNormal) {
+    filament::TransformManager& tm = engine_->getTransformManager();
     for (size_t i = 0; i < reflectives_.size(); ++i) {
-      Drawable* drawable = reflectives_[i];
+      Renderable* renderable = reflectives_[i];
 
-      SetupReflectionCamera(drawable->GetTransform(), camera_, reflect_camera_);
+      // We assume the 0th entity is the reflective entity.
+      const utils::Entity entity = (*renderable)[0];
+      const mat4 transform(tm.getTransform(tm.getInstance(entity)));
+      SetupReflectionCamera(transform, camera_, reflect_camera_);
 
       // Hide reflective surface from its own reflection pass.
-      drawable->GetRenderable().SetLayerMask(0x00);
+      renderable->SetLayerMask(0x00);
 
       // Render the reflection to its render target.
       reflect_view_->setRenderTarget(
@@ -280,7 +281,7 @@ void SceneView::Render(filament::Renderer* renderer,
       renderer->render(reflect_view_);
 
       // Unhide the reflective surface.
-      drawable->GetRenderable().SetLayerMask(0x01);
+      renderable->SetLayerMask(0x01);
     }
   }
 
@@ -293,24 +294,24 @@ void SceneView::Render(filament::Renderer* renderer,
   }
 }
 
-void SceneView::AddReflectiveDrawable(Drawable* drawable) {
+void SceneView::AddReflectiveRenderable(Renderable* renderable) {
   const int index = reflectives_.size();
-  reflectives_.push_back(drawable);
+  reflectives_.push_back(renderable);
 
   // Ensure we have the same number of render targets as we do reflective
-  // drawables.
+  // renderables.
   while (reflect_targets_.size() < reflectives_.size()) {
     reflect_targets_.push_back(std::make_unique<RenderTarget>(
         engine_, RenderTargetTextureType::kReflectionColor,
         RenderTargetTextureType::kDepth));
   }
 
-  // Prepare a render target for the reflective drawable.
+  // Prepare a render target for the reflective renderable.
   auto viewport = reflect_view_->getViewport();
   auto& target = reflect_targets_[index];
   target->Prepare(viewport.width, viewport.height);
 
-  Material& material = drawable->GetMaterial();
+  Material& material = renderable->GetMaterial();
   Material::Textures textures = material.GetTextures();
   textures.reflection = target->GetColorTexture();
   material.UpdateTextures(textures);

src/experimental/filament/filament/scene_view.h

@@ -27,9 +27,9 @@
 #include <filament/View.h>
 #include <mujoco/mujoco.h>
 #include "experimental/filament/filament/color_grading_options.h"
-#include "experimental/filament/filament/drawable.h"
 #include "experimental/filament/filament/light.h"
 #include "experimental/filament/filament/material.h"
+#include "experimental/filament/filament/renderable.h"
 #include "experimental/filament/filament/render_target.h"
 
 namespace mujoco {
@@ -47,8 +47,8 @@ class SceneView {
   // Adds/removes entities from the scene.
   void AddToScene(Light* light);
   void RemoveFromScene(Light* light);
-  void AddToScene(Drawable* drawable);
-  void RemoveFromScene(Drawable* drawable);
+  void AddToScene(Renderable* renderable);
+  void RemoveFromScene(Renderable* renderable);
   void AddToScene(filament::Skybox* skybox);
   void RemoveFromScene(filament::Skybox* skybox);
   void AddToScene(filament::IndirectLight* indirect_light);
@@ -85,9 +85,9 @@ class SceneView {
   SceneView& operator=(const SceneView&) = delete;
 
  private:
-  // Marks a drawable as reflective. Reflective drawables have to be rendered
-  // in their own passes to create the reflective texture.
-  void AddReflectiveDrawable(Drawable* drawable);
+  // Marks a renderable as reflective. Reflective renderables have to be
+  // rendered in their own passes to create the reflective texture.
+  void AddReflectiveRenderable(Renderable* renderable);
 
   filament::Engine* engine_ = nullptr;
   filament::Scene* scene_ = nullptr;
@@ -99,7 +99,7 @@ class SceneView {
 
   // Scene objects.
   std::unordered_set<Light*> lights_;
-  std::unordered_set<Drawable*> drawables_;
+  std::unordered_set<Renderable*> renderables_;
   filament::Skybox* skybox_ = nullptr;
   filament::IndirectLight* indirect_light_ = nullptr;
 
@@ -107,8 +107,8 @@ class SceneView {
   filament::View* reflect_view_ = nullptr;
   filament::Camera* reflect_camera_ = nullptr;
 
-  // The list of reflective drawables and their corresponding render targets.
-  std::vector<Drawable*> reflectives_;
+  // The list of reflective renderables and their corresponding render targets.
+  std::vector<Renderable*> reflectives_;
   std::vector<std::unique_ptr<RenderTarget>> reflect_targets_;
 };
 }  // namespace mujoco