Graphics Programs Reference
In-Depth Information
6. Now, we need to parent the derived object to the base object. To do that, let's select
the derived object, then the base object, and then go to
Object → Parent → Set
.
This way we get the parening hierarchy complete.
The reason to organize these four objects in that specific way is because of the kind of
mechanism we are going to create. The base object will serve the purpose of moving around
in space and also rotaing on its Z axis (thus allowing the camera to look to the let or to the
right). The derived object will then inherit the locaion and Z rotaion of the base object,
but it will be rotated on its X axis to allow the camera to look up and down. That's the way
the mechanism works, by spliing the move and rotate tasks between diferent objects in
the setup. The
mainControl
object was added only to hold certain logic, but it doesn't
intervene physically in the mechanism. A good way to visualize the way the mechanism
works is by rotaing the base object on its Z axis and then the derived object on its X axis,
to see how the camera gets oriented around in each case. Remember though, to clear the
rotaions (
Alt + R
) of the base and derived objects before coninuing.
Logic Bricks Setup
7.
Let's now go to the UV/Image Editor and change the type of editor to a Logic Editor.
But before staring to work on the setup, let's take a look at a screenshot showing it
finished; that way we have some idea where we are heading:
What the screenshot shows are the logic bricks organized in three columns. The
first column is for the
sensors
, the second for the
controllers
, and the third for
the
actuators
. The whole idea of the system is this: Sensors can detect events
(for example, a key press) and send acivaion signals to the controllers they are
connected to when the event is detected. A controller is simulated by the acivaion
signal from one or more of the sensors connected to it and the controller's task is to
decide if one or more of the actuators it is connected to must be sent an acivaion
signal or not. Actuators just wait for an acivaion signal from a controller to perform
some task (for example, moving an object, playing a sound, and so on).
