Miscellaneous HowTos

How to write text into console

Urho implements its own functions for writing text (logging) into console. If you want to use them, first you need to include Log.h

#include "Urho3D/IO/Log.h"

Writing info messages:

LOGINFO(text);

Writing debug messages:

LOGDEBUG(text);

Writing error messages:

LOGERROR(text);

Creating and using your own subsystems

If you have a class inherited from Urho's Object class, you can create a subsystem out of it. The subsystems are helpful, for example, when you want to make a class instance available to every other class inheriting from Object. In this HowTo I will create a subsystem of a class called Settings.

First things to note in subsystem creation (this text is copied from the Urho documentation):

Any Object can be registered to the Context as a subsystem, by using the function RegisterSubsystem(). They can then be accessed by any other Object inside the same context by calling GetSubsystem(). Only one instance of each object type can exist as a subsystem.

So, we can create our own subsystem in just a few steps:

1. Create an instance of your desired class inheriting from Object. I'm using a class called Settings:

Settings* gs = new Settings(context_);

2. Register it to the Context:

context_->RegisterSubsystem(gs);

So now we have created our own subsystem. We can now use it from any Object class we want by using GetSubsystem<NameOfSubsystem>()

Settings* settings = context_->GetSubsystem<Settings>();

How To Enable Post Process Effects

Urho comes with several post process effects (screen effects). Some are listed here: http://urho3d.prophpbb.com/topic55.html

You can enable them like this:

RenderPath* effectRenderPath=viewport->GetRenderPath();
effectRenderPath->Append(cache->GetResource<XMLFile>("PostProcess/AutoExposure.xml"));
effectRenderPath->Append(cache->GetResource<XMLFile>("PostProcess/BloomHDR.xml"));
effectRenderPath->Append(cache->GetResource<XMLFile>("PostProcess/FXAA2.xml"));

The linked forum post uses the Clone() function, that crashed when I use it and just appending the effect to the current RenderPath works too.

The difference between the three effects being appended and not: (I configured the effects to be stronger as per default in their .xml so they may be different if you try it.)