How to use the Automatic Fader
The embedded Automatic Fader can easily manage the cross-fading between two songs loaded inside two different players (also know as "decks"): the Fader object, internally implemented as a COM object, is dedicated to this purpose and can be accessed through the control's
Fader property.
When you need using the
Fader object inside your development, you need to initialise it through a call to the
Fader.Init method, passing the
fading type and the two involved players identifiers.
The fading type can be:
single song based: In this case the cross-fading between the two involved players is performed through the respective loaded songs.
double playlist based: In this case the cross-fading between the two involved players is performed getting sounds from the respective loaded playlists.
single playlist based: In this case the cross-fading between the two involved players is performed getting sounds from the playlist loaded inside one single player: the specific player whose playlist will be used can be set through a call to the Fader.PlayListUseSingle method.
Once the Fader object has been initialised you can configure its behaviour through a set of dedicated properties that will manage the fade-in/fade-out transition.
As you can see on the graphic below, by default cross-fading is based upon a Time/Volume combination:
we have also added a Time/Playback-rate combination that allows the creation of the so called "Breakdown effect" that simulates the switch off of the deck rotor engine: you can choose this behaviour through the following property:
The available properties are the following:
Fader.FadeStartFromEnd: expressed in milliseconds, determines when the fader will automatically start the cross-fading
Fader.FadeInLength: expressed in milliseconds, determines the duration of the fade-in phase
Fader.FadeInSeekPos: expressed in milliseconds, determines the initial position of the song fading-in: in case that the song fading-in is in "paused" state, this parameter is ignored and the actual position is taken.
In case you should need to give the possibility to start a manual cross-fading, without the need to wait reaching the predisposed position, you can use the
Fader.StartManualFading method.
The total time required for the cross-fading is immediately available inside the
Fader.TotalMixingTime property (read-only).
If you need to disable the use of the Automatic Fader, you will have to call the
Fader.Exit method that will remove the involved synchronisation; a new call to the
Fader.Init method will enable again the Automatic Fader.
You can synchronise the container application with the cross-fading process catching a set of predefined events:
FadingVolumeChanged: occurs several times, for each of the involved players, during the volume sliding: allows to know in real-time the player's volume.
FadeOutStarted: occurs when the song fading-out starts lowering its volume
The Fader.Display property
Another useful feature of the embedded Automatic Fader is the possibility to display its visual representation through the
Fader.Display property that works in a way very similar to the other Visual Feedbacks: this property must be associated, through the call to the
Fader.Display.Create method, to an existing window that will be used as a surface for the graphic rendering; below you can see a screenshot of our Demo application that shows it:
Note that also the
Fader.Display property is internally implemented through the
Fader.Display COM object, so you have full customisation capabilities about the display coloring; here is the set of available properties and methods:
Below you can find a graphic that gives an idea of the involved elements:
A sample of use of the Fader object and of the Fader.Display object in Visual Basic 6 and Visual C++ 6 can be found inside the following sample installed with the product's setup package:
- Fader
