Ogre 3D 1.7 Beginner's Guide

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Time for action — creating a directional light

Delete all the old code in createScene(), except for the plane-related code.

Create a light and set the light type to directional light:

Ogre::Light* light = mSceneMgr->createLight("Light1");
light->setType(Ogre::Light::LT_DIRECTIONAL);

Set the light to a white color and the light direction to shine in a down-right direction:

light->setDiffuseColour(Ogre::ColourValue(1.0f,1.0f,1.0f));
light->setDirection(Ogre::Vector3(1,-1,0));

Compile and run the application.

What just happened?

We created a directional light and set it to shine down and rightwards with setDirection(1,-1,0). In the previous examples, we always had a rather black plane and a small part of the plane was illuminated by our pointlight or spotlight. Here, we used a directional light and hence the complete plane is illuminated. As said before, a directional light can be thought of as the sun, and the sun doesn't have a falloff radius or anything else. So when it shines, it illuminates everything there is; the same is true for our directional light.

Pop quiz — different light types

Recall all three light types that Ogre 3D has and state the differences.