Example of using View3D

I’d like to create a view layout in my main window with 4 viewports (similar to CAD programs). I’ve managed to do this by manually giving the default window renderer 4 viewports and sizing them appropriately, but I have noticed that there’s a View3D UI element that can supposedly render a scene. However, when I try to use this, nothing gets drawn to the screen.

void CalliperApplication::Start()
{
	Urho3D::ResourceCache* cache = GetSubsystem<Urho3D::ResourceCache>();
	Urho3D::Graphics* graphics = GetSubsystem<Urho3D::Graphics>();
	Urho3D::UI* ui = GetSubsystem<Urho3D::UI>();

	graphicsWidth_ = graphics->GetWidth();
	graphicsHeight_ = graphics->GetHeight();

	ui->GetRoot()->SetDefaultStyle(cache->GetResource<Urho3D::XMLFile>("UI/DefaultStyle.xml"));

	sampleScene_ = new SampleScene(context_);
	sampleScene_->Initialise();

	// Old code - draws 4 viewports on screen:
	/*Urho3D::Renderer* renderer = GetSubsystem<Urho3D::Renderer>();
	renderer->SetNumViewports(4);

	for ( uint32_t viewportIndex = 0; viewportIndex < 4; ++viewportIndex )
	{
		Urho3D::SharedPtr<Urho3D::Camera> camera = sampleScene_->cameras_[viewportIndex];
		Urho3D::SharedPtr<Urho3D::Viewport> viewport(new Urho3D::Viewport(context_ , sampleScene_->scene_, camera, RectForViewport(viewportIndex)));
		renderer->SetViewport(viewportIndex, viewport);
	}*/

	// New code - everything is black:
	Urho3D::SharedPtr<Urho3D::View3D> view(new Urho3D::View3D(context_));
	view->SetView(sampleScene_->scene_, sampleScene_->cameras_[0], false);
	ui->GetRoot()->AddChild(view);

	SubscribeToEvent(Urho3D::E_BEGINFRAME, URHO3D_HANDLER(CalliperApplication, HandleBeginFrame));
	SubscribeToEvent(Urho3D::E_ENDFRAME, URHO3D_HANDLER(CalliperApplication, HandleEndFrame));
	SubscribeToEvent(Urho3D::E_KEYDOWN, URHO3D_HANDLER(CalliperApplication, HandleKeyDown));
	SubscribeToEvent(Urho3D::E_UPDATE, URHO3D_HANDLER(CalliperApplication, HandleUpdate));
	SubscribeToEvent(Urho3D::E_SCREENMODE, URHO3D_HANDLER(CalliperApplication, HandleScreenModeChanged));
}

I may be using the View3D in the wrong way, I’m not sure. Are there any examples of how it’s supposed to be set up?

From this code, it looks like You’re not setting the size of Your View3D.
View3D element is used several times in the editor, take a look at EditorMaterial.as, EditorParticleEffect.as or EditorResourceBrowser.as - You can find there examples of setting it up (it’s script, but it’s almost the same in c++).
You may also want to go through the EditorView.as - there are implementations of multiple viewports layouts (but it doesn’t use View3D).

Awesome, setting width and height seemed to work! I’d only been searching through C++ files so I hadn’t realised there were View3Ds in script files.