Nodes Database - Learning Unreal Engine iOS Game Development - page 210

Appendix A. Nodes Database
In previous chapters, you've been using lots of nodes to build up the game logic. Of course,
the nodes you used with the examples in this topic are not all of the nodes that Unreal
Engine 4 contains, but they were the most essential ones you needed to build the game lo-
gic. Some of these nodes may be changed in the future while others may be removed.
However, as of now you will have this small appendix as a reference for the most common
nodes used during this topic. You can come here anytime to learn about the usage of a spe-
cific node you found while looking into the project files and blueprints. The most common
nodes are:
• Event Begin Play : Anything connected to this node will start executing itself once
the game starts, or once the actor is spawned into the world.
• Event Tick : Anything connected to this node will be executed in every frame as
long as the game is running.
• InputTouch : This is an event node, which means that it fires itself when the event
takes place. As the name implies, it will be fired when a touch action takes place.
You can execute some functions when the touch is pressed or released, and this can
be done using data such as the touch location or the finger index
• Event Begin Input Touch : This is an event node that fires itself when a touch ac-
tion is initiated, and can only pass the finger index.
• Event End Input Touch : This is an event node that fires itself when a touch action
ends, and can only pass the finger index.
• Event Touch Enter : This is an event node that fires itself when a touch input
enters a collision area, such as the start of overlapping of a collider. This can only
pass the finger index.
• Event Touch Leave : This is an event node that fires itself when a touch input
leaves a collision area, such as completion of overlapping of a collider. This can
only pass the finger index.
• Get Dynamic Material Instance : If the current mesh has a dynamic material, then
accessing it with this node is the best way to start changing some values (such as
color) of this material. The node needs a target mesh and source material as inputs.
• Set Vector Parameter Value : This is a node that is usually used with dynamic ma-
terials to set its parameter. It needs a target, parameter name, and a value to be set
to.
• Custom Event : This is an empty node that represents a set of procedurals to be
called. You can imagine it to be a function.