diff --git a/src/experimental/studio/app.cc b/src/experimental/studio/app.cc
index 87cb8c46..a214a092 100644
--- a/src/experimental/studio/app.cc
+++ b/src/experimental/studio/app.cc
@@ -284,9 +284,9 @@ void App::HandleMouseEvents() {
 
   // Left double click.
   if (data && ImGui::IsMouseDoubleClicked(ImGuiMouseButton_Left)) {
-    toolbox::PickResult picked =
-        toolbox::Pick(mouse_x, mouse_y, window_.get(), renderer_.get(),
-                      physics_.get(), vis_options_);
+    toolbox::PickResult picked = toolbox::Pick(
+        model, data, &camera_, mouse_x, mouse_y, window_->GetAspectRatio(),
+        &renderer_->GetScene(), &vis_options_);
     if (picked.body >= 0) {
       perturb_.select = picked.body;
       perturb_.flexselect = picked.flex;
@@ -305,9 +305,9 @@ void App::HandleMouseEvents() {
 
   // Right double click.
   if (ImGui::IsMouseDoubleClicked(ImGuiMouseButton_Right)) {
-    toolbox::PickResult picked =
-        toolbox::Pick(mouse_x, mouse_y, window_.get(), renderer_.get(),
-                      physics_.get(), vis_options_);
+    toolbox::PickResult picked = toolbox::Pick(
+        model, data, &camera_, mouse_x, mouse_y, window_->GetAspectRatio(),
+        &renderer_->GetScene(), &vis_options_);
     mju_copy3(camera_.lookat, picked.point);
     if (picked.body > 0 && io.KeyCtrl) {
       camera_.type = mjCAMERA_TRACKING;
@@ -457,11 +457,11 @@ void App::HandleKeyboardEvents() {
   // Camera shortcuts.
   if (model) {
     if (ImGui_IsChordJustPressed(ImGuiKey_Escape)) {
-      ui_.camera_idx = toolbox::SetCamera(*model, camera_, 0);
+      ui_.camera_idx = toolbox::SetCamera(model, &camera_, 0);
     } else if (ImGui_IsChordJustPressed(ImGuiKey_LeftBracket)) {
-      ui_.camera_idx = toolbox::SetCamera(*model, camera_,ui_.camera_idx - 1);
+      ui_.camera_idx = toolbox::SetCamera(model, &camera_,ui_.camera_idx - 1);
     } else if (ImGui_IsChordJustPressed(ImGuiKey_RightBracket)) {
-      ui_.camera_idx = toolbox::SetCamera(*model, camera_, ui_.camera_idx + 1);
+      ui_.camera_idx = toolbox::SetCamera(model, &camera_, ui_.camera_idx + 1);
     }
   }
 
@@ -570,7 +570,7 @@ void App::SaveSettings() {
 
 void App::SetCamera(int idx) {
   if (Model()) {
-    ui_.camera_idx = ::mujoco::toolbox::SetCamera(*Model(), camera_, idx);
+    ui_.camera_idx = ::mujoco::toolbox::SetCamera(Model(), &camera_, idx);
   }
 }
 
diff --git a/src/experimental/toolbox/interaction.cc b/src/experimental/toolbox/interaction.cc
index 54355d8a..b1425935 100644
--- a/src/experimental/toolbox/interaction.cc
+++ b/src/experimental/toolbox/interaction.cc
@@ -13,45 +13,39 @@
 // limitations under the License.
 
 #include "experimental/toolbox/interaction.h"
+
 #include <algorithm>
 
-#include "experimental/toolbox/physics.h"
-#include "experimental/toolbox/renderer.h"
-#include "experimental/toolbox/window.h"
 #include <mujoco/mujoco.h>
 
 namespace mujoco::toolbox {
 
-PickResult Pick(float x, float y, Window* window, Renderer* renderer,
-                Physics* physics, const mjvOption& vis_options) {
-  const float w = static_cast<float>(window->GetWidth());
-  const float h = static_cast<float>(window->GetHeight());
-  const float aspect_ratio = w / h;
-
+PickResult Pick(const mjModel* m, const mjData* d, const mjvCamera* camera,
+                float x, float y, float aspect_ratio, const mjvScene* scene,
+                const mjvOption* vis_options) {
   PickResult result;
   result.body =
-      mjv_select(physics->GetModel(), physics->GetData(), &vis_options,
-                 aspect_ratio, x, 1.0f - y, &renderer->GetScene(), result.point,
-                 &result.geom, &result.flex, &result.skin);
+      mjv_select(m, d, vis_options, aspect_ratio, x, 1.0f - y, scene,
+                 result.point, &result.geom, &result.flex, &result.skin);
   return result;
 }
 
-int SetCamera(const mjModel& model, mjvCamera& camera, int request_idx) {
+int SetCamera(const mjModel* m, mjvCamera* camera, int request_idx) {
   // 0 = free, 1 = tracking, 2+ = fixed
-  int camera_idx = std::clamp(request_idx, 0, std::max(model.ncam + 1, 0));
+  int camera_idx = std::clamp(request_idx, 0, std::max(m->ncam + 1, 0));
   if (camera_idx == 0) {
-    camera.type = mjCAMERA_FREE;
+    camera->type = mjCAMERA_FREE;
   } else if (camera_idx == 1) {
-    if (camera.trackbodyid >= 0) {
-      camera.type = mjCAMERA_TRACKING;
-      camera.fixedcamid = -1;
+    if (camera->trackbodyid >= 0) {
+      camera->type = mjCAMERA_TRACKING;
+      camera->fixedcamid = -1;
     } else {
-      camera.type = mjCAMERA_FREE;
+      camera->type = mjCAMERA_FREE;
       camera_idx = 0;
     }
   } else {
-    camera.type = mjCAMERA_FIXED;
-    camera.fixedcamid = camera_idx - 2;
+    camera->type = mjCAMERA_FIXED;
+    camera->fixedcamid = camera_idx - 2;
   }
 
   return camera_idx;
diff --git a/src/experimental/toolbox/interaction.h b/src/experimental/toolbox/interaction.h
index 15b486b3..3da9039f 100644
--- a/src/experimental/toolbox/interaction.h
+++ b/src/experimental/toolbox/interaction.h
@@ -15,9 +15,6 @@
 #ifndef MUJOCO_SRC_EXPERIMENTAL_TOOLBOX_INTERACTION_H_
 #define MUJOCO_SRC_EXPERIMENTAL_TOOLBOX_INTERACTION_H_
 
-#include "experimental/toolbox/physics.h"
-#include "experimental/toolbox/renderer.h"
-#include "experimental/toolbox/window.h"
 #include <mujoco/mujoco.h>
 
 namespace mujoco::toolbox {
@@ -32,8 +29,9 @@ struct PickResult {
 };
 
 // Returns information about the object (if any) under the mouse cursor.
-PickResult Pick(float x, float y, Window* window, Renderer* renderer,
-                Physics* physics, const mjvOption& vis_options);
+PickResult Pick(const mjModel* m, const mjData* d, const mjvCamera* camera,
+                float x, float y, float aspect_ratio, const mjvScene* scene,
+                const mjvOption* vis_options);
 
 // Updates the camera according to the requested index using this convention:
 //
@@ -45,7 +43,7 @@ PickResult Pick(float x, float y, Window* window, Renderer* renderer,
 // convention. Note the returned index may differ from the request if the
 // request was invalid (index was out of range or tracking camera was not
 // available).
-int SetCamera(const mjModel& model, mjvCamera& camera, int request_idx);
+int SetCamera(const mjModel* model, mjvCamera* camera, int request_idx);
 
 }  // namespace mujoco::toolbox
 
diff --git a/src/experimental/toolbox/window.h b/src/experimental/toolbox/window.h
index adf6d2b3..9a52851c 100644
--- a/src/experimental/toolbox/window.h
+++ b/src/experimental/toolbox/window.h
@@ -68,10 +68,15 @@ class Window {
   // Sets the title of the window.
   void SetTitle(std::string_view title);
 
-  // Returns the current size of the window.
+  // Returns information related to the current size of the window.
   int GetWidth() const { return width_; }
   int GetHeight() const { return height_; }
   float GetScale() const { return scale_; }
+  float GetAspectRatio() const {
+    return height_ > 0
+               ? static_cast<float>(width_) / static_cast<float>(height_)
+               : 1.0f;
+  }
 
   // Returns the path to a file that was dropped on the window. Once called,
   // the value will be cleared until the next time a file is dropped.