Ogre 3D 1.7 Beginner's Guide

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Time for action — controlling Sinbad

We use the previous code and add this code where we need, as we did before. We will create a WASD control for Sinbad with the following code:

Replace the line where we translate the node in the FrameListener with a zero vector called translate:
```
Ogre::Vector3 translate(0,0,0);
```

Then add the following keyboard query after the escape query:

if(_key->isKeyDown(OIS::KC_W))
{
translate += Ogre::Vector3(0,0,-10);
}

Now add the code to the other three keys. It is basically the same, only the key code and the direction of the vector changes:

if(_key->isKeyDown(OIS::KC_S))
{
translate += Ogre::Vector3(0,0,10);
}
if(_key->isKeyDown(OIS::KC_A))
{
translate += Ogre::Vector3(-10,0,0);
}
if(_key->isKeyDown(OIS::KC_D))
{
translate += Ogre::Vector3(10,0,0);
}

Now use the translate vector to translate the model, and keep in mind to use time-based and not frame-based movement:
```
_node->translate(translate*evt.timeSinceLastFrame);
```
Compile and run the application, and you should be able to control Sinbad with the WASD keys

What just happened?

We added a basic movement control using the WASD keys. We queried all four keys and built the accumulative movement vector. We then applied this vector to the model using time-based movement.

Have a go hero — using a speed factor for movement

One downside of this approach is that when we want to change the movement speed of the model, we have to modify four vectors. A better way would be to use the vectors only to indicate the movement direction and use a float variable as the speed factor and multiply the translate vector by it. Change the code to use a movement-speed variable.