Use AbstractFeature<dimensions, T>, AbstractGroupedFeature<...>,
AbstractFeatureGroup<...>, FeatureGroup<...> like before and add two
kinds of aliases instead of only one, one with *Basic* for abstract type
and one for Float type.
Partially reverts commit 572efce3f7.
Use Animable<dimensions, T> and AnimableGroup<dimensions, T> like before
and add two kinds of aliases instead of only one:
BasicAnimable[Group]2D<T>/BasicAnimable[Group]3D<T> for abstract type
and Animable[Group]2D/Animable[Group]3D for Float.
Partially reverts commit c32c12b387.
Removed workarounds for alias templates, variadic templates and
anonymous enums, but 1.8.2 has some bug with forward declarations
causing classes to appear in default namespace, breaking
cross-references.
It prevents unwanted implicit conversions from e.g. nullptr to Camera,
Vector2 to Physics::Point etc. By making all the constructors explicit
it is easier to routinely add the keyword to all new classes instead of
thinking about cases when to add and when not to.
Allows to animate objects, pause, repeat and resume the animations. The
user implements animation step and can perform actions on state changes.
Each Animable is part of some group which is optimized for case when no
animation is running, thus it is possible to create multiple independent
"animation islands" to improve performance.