In the previous chapter, we discussed the importance of memory and how it can be used to store data inside a computer. We spoke about how memory is reserved for your program using variables, and how we can include different types of information in our variables.
In this chapter, we will talk about how to control the flow of our program and how we can change what code gets executed by branching the code using control flow statements. Here, we'll discuss the different types of control flow, as follows:
- If statements
- How to check whether things are equal using the
==operator - Else statements
- How to test for inequalities (that is, how to check whether one number is greater or smaller than another using the operators >, >=, <, <=, and !=)
- Using logical operators (such as not (!), and (&&), or (||))
- Our first example project with Unreal Engine
- Branching in more than two ways:
- The else if statement
- The switch statement
The computer code we wrote in Chapter 2, Variables and Memory went in one direction: straight down. Sometimes, we might want to be able to skip parts of the code. We might want the code to be able to branch in more than one direction. Schematically, we can represent this in the following manner:
A flowchart
In other words, we want the option to not run certain lines of code under certain conditions. The preceding figure is called a flowchart. According to this flowchart, if and only if we are hungry, then we will go prepare a sandwich, eat it, and then go and rest on the couch. If we are not hungry, then there is no need to make a sandwich, so we will simply rest on the couch.
We'll use flowcharts in this book only sometimes, but in UE4, you can even use flowcharts to program your game (using something called blueprints).