Compute optimal scene hierarchy width

Author: Meakk

application/F3DOptionsTools.h

@@ -122,7 +122,7 @@ static inline const std::map<std::string_view, std::string_view> LibOptionsNames
   { "fps", "ui.fps" },
   { "filename", "ui.filename" },
   { "metadata", "ui.metadata" },
-  { "scene-hierarchy", "ui.scene_hierarchy" },
+  { "scene-hierarchy", "ui.scene_hierarchy.enable" },
   { "notifications", "ui.notifications.enable" },
   { "hdri-filename", "ui.hdri_filename" },
   { "blur-background", "render.background.blur.enable" },

doc/libf3d/03-OPTIONS.md

@@ -576,13 +576,17 @@ Set the opacity of the backdrop behind the UI elements. Value is between 0.0 (fu
 
 CLI: `--backdrop-opacity`.
 
-### `ui.scene_hierarchy` (_bool_, default: `false`)
+### `ui.scene_hierarchy.enable` (_bool_, default: `false`)
 
 Display the _scene hierarchy_ as a tree representing the internal structure of the model, with checkboxes allowing to hide or show individual parts.
 By default the tree is only expanded enough to show nodes that have meaningful names, but all nodes can be fully expanded manually.
 
 CLI: `--scene-hierarchy`.
 
+### `ui.scene_hierarchy.max_width` (_int_, default: `600`)
+
+Maximum initial width of the _scene hierarchy_ widget.
+
 ### `ui.notifications.enable` (_bool_, default: `false`)
 
 Show notifications at the bottom left of the viewport.

library/options.json

@@ -296,8 +296,14 @@
       "default_value": "false"
     },
     "scene_hierarchy": {
-      "type": "bool",
-      "default_value": "false"
+      "enable": {
+         "type": "bool",
+         "default_value": "false"
+      },
+      "max_width": {
+        "type": "int",
+        "default_value": "600"
+      }
     },
     "notifications": {
       "enable": {

library/src/interactor_impl.cxx

@@ -1714,7 +1714,7 @@ interactor& interactor_impl::initBindings()
   this->addBinding({mod_t::NONE, "N"}, "toggle ui.filename","Scene", std::bind(docTgl, "Filename", std::cref(opts.ui.filename)), f3d::interactor::BindingType::TOGGLE);
   this->addBinding({mod_t::NONE, "M"}, "toggle ui.metadata","Scene", std::bind(docTgl, "Metadata", std::cref(opts.ui.metadata)), f3d::interactor::BindingType::TOGGLE);
   this->addBinding({mod_t::SHIFT, "N"}, "toggle ui.hdri_filename","Scene", std::bind(docTgl, "HDRI filename", std::cref(opts.ui.hdri_filename)), f3d::interactor::BindingType::TOGGLE);
-  this->addBinding({mod_t::SHIFT, "H"}, "toggle ui.scene_hierarchy","Scene", std::bind(docTgl, "Scene hierarchy", std::cref(opts.ui.scene_hierarchy)), f3d::interactor::BindingType::TOGGLE);
+  this->addBinding({mod_t::SHIFT, "H"}, "toggle ui.scene_hierarchy.enable","Scene", std::bind(docTgl, "Scene hierarchy", std::cref(opts.ui.scene_hierarchy.enable)), f3d::interactor::BindingType::TOGGLE);
   this->addBinding({mod_t::NONE, "Z"}, "toggle ui.fps","Scene", std::bind(docTgl, "FPS Counter", std::cref(opts.ui.fps)), f3d::interactor::BindingType::TOGGLE);
 #endif
 #if F3D_MODULE_RAYTRACING

library/src/window_impl.cxx

@@ -459,7 +459,8 @@ void window_impl::UpdateDynamicOptions()
   renderer->SetFilenameInfo(opt.ui.filename_info);
   renderer->ShowMetaData(opt.ui.metadata);
   renderer->ShowHDRIFilename(opt.ui.hdri_filename);
-  renderer->ShowSceneHierarchy(opt.ui.scene_hierarchy);
+  renderer->ShowSceneHierarchy(opt.ui.scene_hierarchy.enable);
+  renderer->SetSceneHierarchyMaxWidth(opt.ui.scene_hierarchy.max_width);
   renderer->ShowCheatSheet(opt.ui.cheatsheet);
   renderer->ShowConsole(opt.ui.console);
   renderer->ShowMinimalConsole(opt.ui.minimal_console);

vtkext/private/module/vtkF3DImguiActor.cxx

@@ -239,6 +239,61 @@ class vtkF3DRenderDataAssemblyVisitor : public vtkDataAssemblyVisitor
 };
 vtkStandardNewMacro(vtkF3DRenderDataAssemblyVisitor);
 
+/**
+ * Visitor used to traverse a full tree (one per importer).
+ * It will take care of estimate the maximum width of the tree nodes in order to set the width of
+ * the scene hierarchy UI widget.
+ */
+class vtkF3DMaxWidthAssemblyVisitor : public vtkDataAssemblyVisitor
+{
+public:
+  static vtkF3DMaxWidthAssemblyVisitor* New();
+  vtkTypeMacro(vtkF3DMaxWidthAssemblyVisitor, vtkDataAssemblyVisitor);
+
+  float GetMaxWidth() const
+  {
+    return this->MaxWidth;
+  }
+
+protected:
+  bool GetTraverseSubtree(int nodeid) override
+  {
+    return this->GetAssembly()->GetAttributeOrDefault(nodeid, "f3d_collapsed", 0) == 0;
+  }
+
+  void Visit(int nodeid) override
+  {
+    const char* defaultLabel =
+      this->GetAssembly()->GetNumberOfChildren(nodeid) > 0 ? "<group>" : "<object>";
+
+    float width =
+      ImGui::CalcTextSize(this->GetAssembly()->GetAttributeOrDefault(nodeid, "label", defaultLabel))
+        .x;
+
+    // arrow or bullet
+    width += ImGui::GetFontSize();
+
+    // spacing between arrow/bullet and checkbox
+    width += ImGui::GetStyle().ItemSpacing.x;
+
+    // checkbox
+    width += ImGui::GetFontSize() + ImGui::GetStyle().ItemInnerSpacing.x;
+
+    // indentation for parent nodes
+    while (nodeid != vtkDataAssembly::GetRootNode())
+    {
+      width += ImGui::GetStyle().IndentSpacing;
+      nodeid = this->GetAssembly()->GetParent(nodeid);
+    }
+
+    this->MaxWidth = std::max(this->MaxWidth, width);
+  }
+
+private:
+  float MaxWidth = 0.f;
+};
+vtkStandardNewMacro(vtkF3DMaxWidthAssemblyVisitor);
+
 }
 
 struct vtkF3DImguiActor::Internals
@@ -586,8 +641,14 @@ void vtkF3DImguiActor::RenderSceneHierarchy(vtkOpenGLRenderWindow* renWin)
   const ImGuiViewport* viewport = ImGui::GetMainViewport();
   assert(viewport);
 
+  vtkF3DRenderer* ren = vtkF3DRenderer::SafeDownCast(renWin->GetRenderers()->GetFirstRenderer());
+  assert(ren != nullptr);
+
+  vtkF3DMetaImporter* importer = ren->GetMetaImporter();
+  assert(importer != nullptr);
+
   constexpr float margin = F3DStyle::GetDefaultMargin();
-  constexpr float defaultWidth = 200.f;
+  float defaultWidth = this->CalculateHierarchyWidth(importer);
   float winHeight = viewport->WorkSize.y - 2.0f * margin;
 
   float posX = margin;
@@ -608,12 +669,6 @@ void vtkF3DImguiActor::RenderSceneHierarchy(vtkOpenGLRenderWindow* renWin)
 
   ImGui::Begin("Scene Hierarchy", nullptr, flags);
 
-  vtkF3DRenderer* ren = vtkF3DRenderer::SafeDownCast(renWin->GetRenderers()->GetFirstRenderer());
-  assert(ren != nullptr);
-
-  vtkF3DMetaImporter* importer = ren->GetMetaImporter();
-  assert(importer != nullptr);
-
   for (int i = 0; i < importer->GetImporterInfoCount(); i++)
   {
     vtkF3DMetaImporter::ImporterInfo info = importer->GetImporterInfo(i);
@@ -629,6 +684,30 @@ void vtkF3DImguiActor::RenderSceneHierarchy(vtkOpenGLRenderWindow* renWin)
   ImGui::End();
 }
 
+//----------------------------------------------------------------------------
+float vtkF3DImguiActor::CalculateHierarchyWidth(vtkF3DMetaImporter* importer)
+{
+  float maxWidth = 0.0f;
+  const float indentPerLevel = ImGui::GetStyle().IndentSpacing;
+  const float treeArrowWidth = ImGui::GetFontSize();
+  const float checkboxWidth = ImGui::GetFrameHeight() + ImGui::GetStyle().ItemInnerSpacing.x;
+
+  for (int i = 0; i < importer->GetImporterInfoCount(); i++)
+  {
+    vtkF3DMetaImporter::ImporterInfo info = importer->GetImporterInfo(i);
+
+    vtkNew<::vtkF3DMaxWidthAssemblyVisitor> visitor;
+    info.DataAssembly->Visit(vtkDataAssembly::GetRootNode(), visitor);
+
+    maxWidth = std::max(maxWidth, visitor->GetMaxWidth());
+  }
+
+  float totalWidth =
+    maxWidth + 2.0f * ImGui::GetStyle().WindowPadding.x + ImGui::GetStyle().ScrollbarSize;
+
+  return std::min(totalWidth, static_cast<float>(this->SceneHierarchyMaxWidth));
+}
+
 //----------------------------------------------------------------------------
 void vtkF3DImguiActor::RenderDropZone()
 {

vtkext/private/module/vtkF3DImguiActor.h

@@ -12,6 +12,7 @@
 
 #include <memory>
 
+class vtkF3DMetaImporter;
 class vtkOpenGLRenderWindow;
 class vtkWindow;
 
@@ -120,6 +121,11 @@ class vtkF3DImguiActor : public vtkF3DUIActor
    * Compute the width of a badge
    */
   float CalcBadgeWidth(const std::string& text);
+
+  /**
+   * Calculate the default width of the scene hierarchy UI widget
+   */
+  float CalculateHierarchyWidth(vtkF3DMetaImporter* importer);
 };
 
 #endif

vtkext/private/module/vtkF3DRenderer.cxx

@@ -1885,6 +1885,12 @@ void vtkF3DRenderer::ConfigureMetaData()
   this->MetaDataConfigured = true;
 }
 
+//----------------------------------------------------------------------------
+void vtkF3DRenderer::SetSceneHierarchyMaxWidth(const int maxWidth)
+{
+  this->UIActor->SetSceneHierarchyMaxWidth(maxWidth);
+}
+
 //----------------------------------------------------------------------------
 void vtkF3DRenderer::ShowSceneHierarchy(bool show)
 {

vtkext/private/module/vtkF3DRenderer.h

@@ -132,6 +132,7 @@ class vtkF3DRenderer : public vtkOpenGLRenderer
   void SetGridColor(const std::vector<double>& color);
   void SetAxesColor(const std::vector<double>& colorXAxis, const std::vector<double>& colorYAxis,
     const std::vector<double>& colorZAxis);
+  void SetSceneHierarchyMaxWidth(const int width);
   ///@}
 
   /**

vtkext/private/module/vtkF3DUIActor.cxx

@@ -190,6 +190,16 @@ void vtkF3DUIActor::SetBackdropOpacity(const double backdropOpacity)
   }
 }
 
+//----------------------------------------------------------------------------
+void vtkF3DUIActor::SetSceneHierarchyMaxWidth(const int width)
+{
+  if (this->SceneHierarchyMaxWidth != width)
+  {
+    this->SceneHierarchyMaxWidth = width;
+    this->Initialized = false;
+  }
+}
+
 //----------------------------------------------------------------------------
 int vtkF3DUIActor::RenderOverlay(vtkViewport* vp)
 {