Irrlicht Engine - Easy Tutorial – Basics

This post is part of my tutorial on how to use Irrlicht Engine and a continuation to the article Irrlicht Engine - Easy Tutorial – Intro.

Let’s view the example I used in the previous post. Here is the code:

#include <irrlicht.h>

using namespace irr;

using namespace core;
using namespace scene;
using namespace video;

using namespace io;
using namespace gui;

int main()

{
 IrrlichtDevice *device = createDevice(
   video::EDT_OPENGL,
   dimension2d<u32>(800, 600),
   16, false, false, false, 0);

 if (!device)
  return 1;

 IVideoDriver* driver = device->getVideoDriver();

 ISceneManager* sceneManager =
   device->getSceneManager();

 sceneManager->addCameraSceneNode();

 while(device->run())

 {
  driver->beginScene(
    true, true, SColor(255,50,130,50));

  sceneManager->drawAll();
  driver->endScene();
 }

 device->drop();
 return 0;
}

This is a very basic application. First thing we need to do is to create Irrlicht device with the createDevice function. The first parameter is video::E_DRIVER_TYPE type and can be video::EDT_DIRECT3D9, video::EDT_DIRECT3D8, video::EDT_OPENGL, video::EDT_NULL, video::EDT_SOFTWARE, video::EDT_BURNINGSVIDEO. I’ll use video::EDT_OPENGL because my Irrlicht binaries are from the official site and they are not built with DirectX. (And I am lazy.)

Next parameter as you can assume is the window size. I won’t discuss the other parameters now as they are not important for my tutorial. In fact I can call createDevice this way:

IrrlichtDevice *device = createDevice(

   video::EDT_OPENGL,
   dimension2d<u32>(800, 600));

When you finish using the device don’t forget to call:

device->drop(); 

You can learn more for the Irrlicht device class here - http://irrlicht.sourceforge.net/docu/classirr_1_1_irrlicht_device.html.

And now the cool part – the scene manager object. It manages the scene nodes, meshes, cameras, lights and so on. Your scene is represented as a hierarchical scene graph.
You obtain a reference to the scene manager object through the call:

device->getSceneManager();

Let’s do something fun with our example. I’ll change our camera to FPS mode – FPS camera in Irrlicht is a camera node suited for a first person shooter. It moves with the arrows and rotates with the mouse.
I’ll add some simple scene nodes as cube and sphere.

To add a FPS camera we must call:

ICameraSceneNode *camera = sceneManager->addCameraSceneNodeFPS();

Our cube:

ISceneNode *cube = sceneManager->

        addCubeSceneNode(15.0f, 0, -1, core::vector3df(150,10,10));

To make the camera look at the cube:

camera->setTarget(cube->getAbsolutePosition());

I’ll add a light source with the default parameters. Without it our objects will look ugly and black. Now they will be ugly but with some light on the front side.

Here is the full code:

#include <irrlicht.h>

using namespace irr;

using namespace core;
using namespace scene;
using namespace video;

using namespace io;
using namespace gui;

int main()

{
 IrrlichtDevice *device = createDevice(
   video::EDT_OPENGL,
   dimension2d<u32>(800, 600));

 if (!device)
  return 1;

 IVideoDriver* driver = device->getVideoDriver();

 ISceneManager* sceneManager =
   device->getSceneManager();

 ICameraSceneNode *camera =
   sceneManager->addCameraSceneNodeFPS();

 ISceneNode *cube = sceneManager->
   addCubeSceneNode(15.0f, 0, -1,
     core::vector3df(150,10,10));

 sceneManager->addSphereSceneNode(
   5.0f, 16, 0, -1,
   core::vector3df(100,30,10));

 sceneManager->addLightSceneNode();

 camera->setTarget(cube->getAbsolutePosition());

 while(device->run())
 {
  driver->beginScene(

    true, true, SColor(255,50,130,50));

  sceneManager->drawAll();
  driver->endScene();
 }

 device->drop();
 return 0;
} 

And the result