PRG Mbox Designer Manual 3.9 - Manual (Page 31)

MBOX ® MEDIA SERVER USER MANUAL 23
Object Effects
Whereas shader-based effects work on individual pixels, Object Effects work on the entire composition of a layer.
This means that Object Effects can work outside the original pixel boundaries of content, allowing them to move the
content without it being cropped. Object Effects can move, rotate, crop, or strobe the content, and can also add
complex openGL manipulations to the 3D aspects of the layer.
Note: Object Effects must be created by PRG's Mbox Development Team.
Transitions
One of Mbox's most powerful features is its ability to perform a timed transition from one piece of content to another
on the same layer. There are two types of transitions within Mbox - Built-in and Object Dissolve. There are about 60
different built-in transitions, but only one Object Dissolve. The built-in transitions are based on shaders, just like the
majority of the layer effects.
Built-In
As with the shader-based Layer effects, the built-in transitions can only work within the original pixel boundaries of
the layer's content. What this means is that if the outgoing and incoming content share the exact same pixel size the
transition can work seamlessly. However, if the two pieces of content are different sizes, the transition will happen in
a frame whose size is defined by that of the larger piece of content. In most cases this should be fine, as the majority
of the built-in transitions still work well like this.
One consideration is that the built-in transitions may not work as desired when other parameters such as position,
rotation, scale, etc. are modified at the same time as the content is changed. In such cases, the other parameters will
change based on the cue timing, while the transition uses the transition timing parameter. This can mean that
parameter changes can precede or lag behind the content transition.
Note: Built-in transitions between different sizes of content will likely produce unexpected results when used with 3D
objects.
Like Effect shaders, built-in transitions can be created by anyone and imported for use in Mbox.
Object Dissolve
The Object Dissolve transition type is special within Mbox. It is not a built-in shader-based transition, but rather it uses
Mbox's ability to support two playback/rendering engines on each layer. When an Object Dissolve transition is
initiated, Mbox automatically begins an opacity crossfade between the two pieces of content, just like you might
perform manually using two different layers.
Because it works like a two-layer opacity crossfade, the Object Dissolve transition can seamlessly move between
content of different sizes and with different values for parameters like position, scale, rotation, and so on.
IMPORTANT! Note that setting the Transition Type parameter to a value of 255 actually tells Mbox to use the
currently selected Object Transition Type! This means that if you are using any 3D object on the layer and the Object
Transition Type parameter is not set to its default value of 0, you will not get an Object Dissolve (i.e., an opacity
crossfade), but instead the specified object transition.