From 83d2ae540e78681c281628570c67981992c3acdd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Pe=C5=82ka?= <michal.pelka@robotec.ai>
Date: Tue, 29 Apr 2025 17:03:23 +0200
Subject: [PATCH] Added possibility to load USD from command line
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Signed-off-by: Michał Pełka <michal.pelka@robotec.ai>
---
 CMakeLists.txt                |  2 +-
 src/main.cpp                  |  8 +++++++-
 src/mainwindow.cpp            | 27 +++++++++++++++++++++++++--
 src/mainwindow.h              | 11 ++++++++++-
 src/views/usdsessionlayer.cpp |  5 +++--
 src/views/usdsessionlayer.h   | 14 ++++++++------
 6 files changed, 54 insertions(+), 13 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6c1a36d..9fff966 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,7 +6,7 @@ include(GNUInstallDirs)
 
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
-
+find_package(X11)
 find_package(pxr REQUIRED)
 find_package(OpenGL REQUIRED)
 
diff --git a/src/main.cpp b/src/main.cpp
index d612ad7..2a43e0c 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -149,7 +149,13 @@ int main(int argc, char** argv)
     glEnable(GL_DEPTH_TEST);
 
     pxr::Model model;
-    pxr::MainWindow mainWindow(&model);
+    std::vector<std::string> params;
+    for (int i =0; i < argc; i++)
+    {
+        params.emplace_back(argv[i]);
+    }
+
+    pxr::MainWindow mainWindow(&model, params);
 
     while (!glfwWindowShouldClose(window)) {
         glfwPollEvents();
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index b506de0..e4c0ce6 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -7,12 +7,23 @@
 #include "views/usdsessionlayer.h"
 #include "views/view.h"
 #include "views/viewport.h"
-
+#include <assert.h>
+#include <iostream>
 PXR_NAMESPACE_OPEN_SCOPE
 
-MainWindow::MainWindow(Model* model) : _model(model)
+MainWindow::MainWindow(Model* model, const std::vector<std::string>& params) : _model(model)
 {
     ResetDefaultViews();
+    if (params.size()>1)
+    {
+        const auto & usdFileName = params[1];
+        auto views = GetViewsOfType(UsdSessionLayer::VIEW_TYPE);
+        assert(!views.empty());
+        UsdSessionLayer* sessionLayerPtr = dynamic_cast<UsdSessionLayer*>(views.front());
+        assert(sessionLayerPtr);
+        std::cout << "Loading "<< usdFileName << std::endl;
+        sessionLayerPtr->LoadUsdStage(usdFileName);
+    }
 };
 
 void MainWindow::Update()
@@ -89,4 +100,16 @@ void MainWindow::AddView(const string viewType)
     }
 }
 
+vector<View*> MainWindow::GetViewsOfType(const string viewType)
+{
+    vector<View*> viewptrs;
+    for (auto &view:_views){
+        if (view->GetViewType() == viewType)
+        {
+            viewptrs.emplace_back(view);
+        }
+    }
+    return viewptrs;
+}
+
 PXR_NAMESPACE_CLOSE_SCOPE
diff --git a/src/mainwindow.h b/src/mainwindow.h
index 5d0b4be..a6c7097 100644
--- a/src/mainwindow.h
+++ b/src/mainwindow.h
@@ -29,8 +29,9 @@ class MainWindow {
          * @brief Construct a new Main Window object
          *
          * @param model the Model of the new Main Window
+         * @param application arguments
          */
-        MainWindow(Model* model);
+        MainWindow(Model* model, const std::vector<std::string>& args);
 
         /**
          * @brief Update the draw call of the main window
@@ -53,7 +54,15 @@ class MainWindow {
          */
         void AddView(const string viewType);
 
+        /**
+        * @brief Gets views of given type
+        *
+        * @param viewType the type of the retrieved view
+        */
+        vector<View*> GetViewsOfType(const string viewType);
+
     private:
+
         vector<View*> _views;
         Model* _model;
 };
diff --git a/src/views/usdsessionlayer.cpp b/src/views/usdsessionlayer.cpp
index f0c58c7..6d1579d 100644
--- a/src/views/usdsessionlayer.cpp
+++ b/src/views/usdsessionlayer.cpp
@@ -34,6 +34,7 @@ UsdSessionLayer::UsdSessionLayer(Model* model, const string label)
     GetModel()->AddSceneIndexBase(sceneIndices.finalSceneIndex);
 
     _SetEmptyStage();
+
 }
 
 const string UsdSessionLayer::GetViewType()
@@ -92,7 +93,7 @@ void UsdSessionLayer::_Draw()
     if (ImGuiFileDialog::Instance()->Display("LoadFile")) {
         if (ImGuiFileDialog::Instance()->IsOk()) {
             string filePath = ImGuiFileDialog::Instance()->GetFilePathName();
-            _LoadUsdStage(filePath);
+            LoadUsdStage(filePath);
         }
         ImGuiFileDialog::Instance()->Close();
     }
@@ -121,7 +122,7 @@ void UsdSessionLayer::_SetEmptyStage()
     GetModel()->SetStage(_stage);
 }
 
-void UsdSessionLayer::_LoadUsdStage(const string usdFilePath)
+void UsdSessionLayer::LoadUsdStage(const string usdFilePath)
 {
     if (!ifstream(usdFilePath)) {
         TF_RUNTIME_ERROR(
diff --git a/src/views/usdsessionlayer.h b/src/views/usdsessionlayer.h
index 474c866..97d6d89 100644
--- a/src/views/usdsessionlayer.h
+++ b/src/views/usdsessionlayer.h
@@ -48,6 +48,13 @@ class UsdSessionLayer : public View {
          */
         ImGuiWindowFlags _GetGizmoWindowFlags() override;
 
+        /**
+        * @brief Load a Usd Stage based on the given Usd file path
+        *
+        * @param usdFilePath a string containing a Usd file path
+        */
+        void LoadUsdStage(const string usdFilePath);
+
     private:
         TextEditor _editor;
         bool _isEditing;
@@ -63,12 +70,7 @@ class UsdSessionLayer : public View {
          */
         void _Draw() override;
 
-        /**
-         * @brief Load a Usd Stage based on the given Usd file path
-         *
-         * @param usdFilePath a string containing a Usd file path
-         */
-        void _LoadUsdStage(const string usdFilePath);
+
 
         /**
          * @brief Set the model to an empty stage