In the standard (2D) FMX environment, we are used to having TLayout instances acting as invisible containers. This lets the developer easily position and size objects (or groups of them) to achieve responsive UIs (as we discussed in Chapter 9, Building Responsive UIs). TLayout instances are invisible at runtime (and to the end user), yet they can be used to group other components and implement relative positioning and sizing. TDummy is the equivalent of TLayout in the 3D conception.
A TDummy component has a cubic shape and its boundaries are rendered only at design time. You can nest as many instances of TDummy as you like and you can size them as you prefer. They also can host other components and the contained component(s) will be relative to the container in terms of position, rotation, visibility, and other qualities (opacity, for example).
It is quite common to use a TDummy instance as the parent of all other components in the...
