Irrlicht Engine Tutorial

In the beginning, everything as usual. Include the needed headers, - ask the user for the rendering driver, create the Irrlicht Device:

- - - - -

#include <irrlicht.h>
-#include <iostream>
-
-using namespace irr;
-
-#pragma comment(lib, "Irrlicht.lib")
-
-int main()
-{
-	// let user select driver type
-
-	video::E_DRIVER_TYPE driverType = video::EDT_DIRECT3D9;
-
-	printf("Please select the driver you want for this example:\n"\
		" (a) Direct3D 9.0c\n (b) Direct3D 8.1\n (c) OpenGL 1.5\n"\
		" (d) Software Renderer\n (e) Apfelbaum Software Renderer\n"\
		" (f) NullDevice\n (otherKey) exit\n\n");
-
-	char i;
-	std::cin >> i;
-
-	switch(i)
	{
		case 'a': driverType = video::EDT_DIRECT3D9;break;
		case 'b': driverType = video::EDT_DIRECT3D8;break;
		case 'c': driverType = video::EDT_OPENGL;   break;
		case 'd': driverType = video::EDT_SOFTWARE; break;
		case 'e': driverType = video::EDT_BURNINGSVIDEO;break;
		case 'f': driverType = video::EDT_NULL;     break;
		default: return 1;
	}	
-
-	// create device and exit if creation failed
-
-	IrrlichtDevice *device =
-		createDevice(driverType, core::dimension2d(640, 480),
-		16, false, false);
-
-	if (device == 0)
-		return 1; // could not create selected driver.
-
-	video::IVideoDriver* driver = device->getVideoDriver();
-	scene::ISceneManager* smgr = device->getSceneManager();
-	gui::IGUIEnvironment* env = device->getGUIEnvironment();

Now, we load an animated mesh to be displayed. As in most examples, - we'll take the fairy md2 model. The difference here: We set the shininess
- of the model to a value other than 0 which is the default value. This - enables specular highlights on the model if dynamic lighting is on. - The value influences the size of the highlights.

- - - - -

// load and display animated fairy mesh
-
-	scene::IAnimatedMeshSceneNode* fairy = smgr->addAnimatedMeshSceneNode(
-		smgr->getMesh("../../media/faerie.md2"));
-
-	if (fairy)
-	{
-		fairy->setMaterialTexture(0, driver->getTexture("../../media/faerie2.bmp")); // set diffuse texture
-		fairy->setMaterialFlag(video::EMF_LIGHTING, true); // enable dynamic lighting
-		fairy->getMaterial(0).Shininess = 20.0f; // set size of specular highlights
-		fairy->setPosition(core::vector3df(-10,0,-100));
-	}

To make specular highlights appear on the model, we need a dynamic - light in the scene. We add one directly in vicinity of the model. - In addition, to make the model not that dark, we set the ambient light - to gray.

- - - - -

-	// add white light
-	scene::ILightSceneNode* light = smgr->addLightSceneNode(0,
-		core::vector3df(-15,5,-105), video::SColorf(1.0f, 1.0f, 1.0f));
-
-	// set ambient light
-	driver->setAmbientLight(video::SColor(0,60,60,60));

The next is just some standard stuff: Add a user controlled camera - to the scene, disable mouse cursor, and add a test cube and let it - rotate to make the scene more interesting.

- - - - -

-	// add fps camera
-	scene::ICameraSceneNode* fpsCamera = smgr->addCameraSceneNodeFPS();
-	fpsCamera->setPosition(core::vector3df(-50,50,-150));
-
-	// disable mouse cursor
-	device->getCursorControl()->setVisible(false);
-
-	// create test cube
-	scene::ISceneNode* test = smgr->addCubeSceneNode(60);
-
-	// let the cube rotate and set some light settings
-	scene::ISceneNodeAnimator* anim = smgr->createRotationAnimator(
-		core::vector3df(0.3f, 0.3f,0));
-
-	test->setPosition(core::vector3df(-100,0,-100));
-	test->setMaterialFlag(video::EMF_LIGHTING, false); // disable dynamic lighting
-	test->addAnimator(anim);
-	anim->drop();
-
-	// set window caption
-	device->setWindowCaption(L"Irrlicht Engine - Render to Texture and Specular Highlights example");

To test out the render to texture feature, we need a render target - texture. These are not like standard textures, but need to be created - first. To create one, we call IVideoDriver::createRenderTargetTexture() - and specify the size of the texture. Please don't use sizes bigger - than the frame buffer for this, because the render target shares the - zbuffer with the frame buffer. And because we want to render the scene - not from the user camera into the texture, we add another, fixed camera - to the scene. But before we do all this, we check if the current running - driver is able to render to textures. If it is not, we simply display - a warning text.

- - - - -

// create render target
-	video::ITexture* rt = 0;
-	scene::ICameraSceneNode* fixedCam = 0;
-	
-
-	if (driver->queryFeature(video::EVDF_RENDER_TO_TARGET))
-	{
-		rt = driver->createRenderTargetTexture(core::dimension2d(256,256));
-		test->setMaterialTexture(0, rt); // set material of cube to render target
-
-		// add fixed camera
-		fixedCam = smgr->addCameraSceneNode(0, core::vector3df(10,10,-80),
-			core::vector3df(-10,10,-100));
-	}
-	else
-	{
-		// create problem text
-		gui::IGUISkin* skin = env->getSkin();
-		gui::IGUIFont* font = env->getFont("../../media/fonthaettenschweiler.bmp");
-		if (font)
-			skin->setFont(font);
-
-		gui::IGUIStaticText* text = env->addStaticText(
-			L"Your hardware or this renderer is not able to use the "\
-			L"render to texture feature. RTT Disabled.",
-			core::rect(150,20,470,60));
-
-		text->setOverrideColor(video::SColor(100,255,255,255));
-	}

Nearly finished. Now we need to draw everything. Every frame, we - draw the scene twice. Once from the fixed camera into the render target - texture and once as usual. When rendering into the render target, - we need to disable the visibilty of the test cube, because it has - the render target texture applied to it.
- That's, wasn't quite complicated I hope. :)

- - - - -

while(device->run())
-	if (device->isWindowActive())
-	{
-		driver->beginScene(true, true, 0);
-
-		if (rt)
-		{
-			// draw scene into render target
-			
-			// set render target texture
-			driver->setRenderTarget(rt, true, true, video::SColor(0,0,0,255));     
-
-			// make cube invisible and set fixed camera as active camera
-			test->setVisible(false);
-			smgr->setActiveCamera(fixedCam);
-
-			// draw whole scene into render buffer
-			smgr->drawAll();                 
-
-			// set back old render target
-			driver->setRenderTarget(0);      
-
-			// make the cube visible and set the user controlled camera as active one
-			test->setVisible(true);
-			smgr->setActiveCamera(fpsCamera);
-		}
-		
-		// draw scene normally
-		smgr->drawAll(); 
-		env->drawAll();
-
-		driver->endScene();
-	}
-
-	if (rt)
-		rt->drop(); // drop render target because we created if with a create() method
-
-	device->drop(); // drop device
-	return 0;
-}
-

- -

	- - Tutorial 13. Render to Texture - -
- - This tutorial shows how to render to a texture using Irrlicht. Render - to texture is a feature with which it is possible to create nice special - effects. In addition, this tutorial shows how to enable specular highlights. - The program which is described here will look like this: - - - -