Resolve Studio assets path dynamically.

PiperOrigin-RevId: 931162732
Change-Id: Ib44a74790facfa797ca2c4f107edb0062a89c117

python/mujoco/experimental/studio/native_viewer.cc

@@ -16,11 +16,13 @@
 #include <cstdint>
 #include <cstdlib>
 #include <cstring>
+#include <filesystem>  // NOLINT(build/c++17)
 #include <memory>
 #include <string>
 #include <string_view>
 #include <vector>
 
+
 #include <fstream>
 #include <imgui.h>
 #include <implot.h>
@@ -28,6 +30,7 @@
 #include <mujoco/experimental/platform/hal/graphics_mode.h>
 #include <mujoco/experimental/platform/hal/renderer.h>
 #include <mujoco/experimental/platform/hal/window.h>
+#include <mujoco/experimental/platform/sys_utils.h>
 #include "structs.h"
 #include <pybind11/eval.h>
 #include <pybind11/pybind11.h>
@@ -48,8 +51,15 @@ static bool IsCrd() {
 }
 
 static std::vector<std::byte> LoadAsset(std::string_view path) {
-  std::string file_path = "assets/" +
+  std::string_view subpath = path.substr(path.find(':') + 1);
-      std::string(path.substr(path.find(':') + 1));
+  static const std::string asset_dir = []() {
+    std::string module_dir =
+        mujoco::platform::GetModuleDir((void*)&LoadAsset);
+    return module_dir.empty()
+               ? "assets"
+               : (std::filesystem::path(module_dir) / "assets").string();
+  }();
+  std::string file_path = asset_dir + "/" + std::string(subpath);
 
   std::ifstream file(file_path, std::ios::binary | std::ios::ate);
   if (!file.is_open()) {

src/experimental/platform/CMakeLists.txt

@@ -22,6 +22,8 @@ target_sources(${MUJOCO_PLATFORM_TARGET_NAME}
     PUBLIC
         helpers.cc
         helpers.h
+        sys_utils.cc
+        sys_utils.h
         hal/egl_utils.cc
         hal/egl_utils.h
         hal/graphics_mode.cc

src/experimental/platform/sys_utils.cc

@@ -0,0 +1,59 @@
+// Copyright 2026 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
+//
+//     https://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.
+
+#include "experimental/platform/sys_utils.h"
+
+#include <filesystem>  // NOLINT(build/c++17)
+#include <string>
+#include <system_error>
+#if defined(_WIN32) || defined(__CYGWIN__)
+  #include <windows.h>
+#else
+  #include <dlfcn.h>
+#endif
+
+namespace mujoco::platform {
+
+std::string GetModuleDir(void* addr) {
+#if defined(_WIN32) || defined(__CYGWIN__)
+  HMODULE hModule = NULL;
+  if (GetModuleHandleExA(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |
+                         GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT,
+                         (LPCSTR)addr, &hModule)) {
+    char path[MAX_PATH];
+    DWORD written = GetModuleFileNameA(hModule, path, sizeof(path));
+    if (written > 0 && written < sizeof(path)) {
+      return std::filesystem::path(path).parent_path().string();
+    }
+  }
+  return "";
+#else
+  Dl_info info;
+  if (dladdr(addr, &info) != 0 && info.dli_fname != nullptr) {
+    std::filesystem::path p(info.dli_fname);
+    if (p.is_absolute()) {
+      return p.parent_path().string();
+    }
+    std::error_code ec;
+    std::filesystem::path cwd = std::filesystem::current_path(ec);
+    if (!ec) {
+      return (cwd / p).parent_path().string();
+    }
+    return p.parent_path().string();
+  }
+  return "";
+#endif
+}
+
+}  // namespace mujoco::platform

src/experimental/platform/sys_utils.h

@@ -0,0 +1,27 @@
+// Copyright 2026 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
+//
+//     https://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_PLATFORM_SYS_UTILS_H_
+#define MUJOCO_SRC_EXPERIMENTAL_PLATFORM_SYS_UTILS_H_
+
+#include <string>
+
+namespace mujoco::platform {
+
+// Returns the path to the directory of the current module (exe or shared lib).
+std::string GetModuleDir(void* addr);
+
+}  // namespace mujoco::platform
+
+#endif  // MUJOCO_SRC_EXPERIMENTAL_PLATFORM_SYS_UTILS_H_

src/experimental/studio/main.cc

@@ -16,6 +16,7 @@
 
 #include <cstdlib>
 #include <cstring>
+#include <filesystem>  // NOLINT(build/c++17)
 #include <fstream>
 #include <ios>
 #include <iosfwd>
@@ -27,6 +28,7 @@
 #include <absl/flags/parse.h>
 #include <mujoco/mujoco.h>
 #include "experimental/platform/hal/graphics_mode.h"
+#include "experimental/platform/sys_utils.h"
 #include "experimental/studio/app.h"
 
 ABSL_FLAG(int, window_width, 1400, "Window width");
@@ -36,7 +38,11 @@ ABSL_FLAG(std::string, gfx, "", "Graphics API");
 
 std::string Resolve(std::string_view path) {
   std::string_view subpath = path.substr(path.find(':') + 1);
-  return std::string("assets/") + std::string(subpath);
+  std::filesystem::path exe_dir = mujoco::platform::GetModuleDir((void*)&Resolve);
+  if (exe_dir.empty()) {
+    return std::string("assets/") + std::string(subpath);
+  }
+  return (exe_dir / "assets" / subpath).string();
 }
 
 class FileResource {