Coding notes - Day one

September 17, 2019

Coding notes - Day one

Here are the notes about coding

Computers don't know what to do, until we tell them. These commands could be simple and like a step by step guide or a recipe.
Commands could also be a little more complicated with conditions and logic. Like only used if we are hungry.
To tell a computer what to do...
We need to understand three elements of a script. Variables
Variables. When programming, we need to deal with lots of data. We store this data inside variables to be called on at a later stage.
There are four main variables. Strings, Int. Float, and Bool.
Strings. Can contain letters, numbers and other characters. Can not be used for calculations. Used for names, text, passwords, etc.
Int. Short for Integer, used for storing numbers with no decimal place. No dots, not 1.1. Used for Mario styled lives like 3 to 0.
Float. Used for storing numbers that can have decimals. Has dots, can be 1.1. Used for RPG style health where it can be between 100% and 0%.
Bool. Short for Boolean. It has one of two possible values. True or False.
Functions
Basically a set of code that runs at certain times depending on what programming language you are using. Any commands we put inside Start will never happen again.
Common functions, Start(), runs at the start of a script. Update(), runs on each frame refresh. FixedUpdate(), same as Update but has a fixed frame rate refresh.
Methods
Commands can be wrapped into a set of instructions called methods. We can reuse this every time we want it.
Synatx
The specific way we write the language a computer understands. Similar to English, we know the end with the (.) The computer knows a line of code has ended is by the (;)
It is important to understand the programming languages syntax as a simple out of place (;) can stop your whole 1000 lines of code from running.
E.g Example of C# for variable private string playerName = "Joe";
Notes. Strings have quotes around their values (""). Private must have a lower case (p). Write the same (n with N and p with p). Must end with (;).
E.g's
public float playerHealth = 100;
public bool isJumping - false;
private sprite heart1In;
private sprite heart1out;
Difference between public and private. Public can be accessed within any variable in the entire script. Private is by the script the variable is in.
E.g's
void Start(){
}
void Update(){
}
void FixedUpdate(){
}
This shows the start and the end of the code/function. Put what you want within the space
E.g's
void Inputs(){
}
private void Inputs(){
}
Can have private or public
Now we have the method, we need to call to it. It is waiting to be referenced. Usually done within one of the main functions. Start() Update() or FixedUpdate().
E.g's
Update(){
Inputs();
}
Extra bits of C#
(==) symbol. We can use this to check if a variable equals something. E.g, If(health ==0)
(If) statements. Use if statements to check the value of something before we run a piece of code
E.g If(health == 0){
GameOver();
}
If the health is not 0 that it will not run
(If else) statements. Like If but has additional conditions and code if the first part is not true
E.g If(velocity.y == 0){
OnGround = true;
}else{
OnGround = false;
}
If the first part of the if statement is meet, the other half will not run
(&&) symbol. We use this if we are trying to check more than one variables before running some code
E.g If(health == 0 && score == 100)
(||) symbol. Means 'or'. We use this to check if one variable or another is true. Only one needs to be true to work
E.g If(health == o || score == 100)
In most cases writing bool variable can be shortened.