Using a struct to improve our dice.

Objectives

1. Review structures.
2. Employ a structure to improve our implementation of a die.

Notes

• We are working on how to make a reusable, independent die
  • I probably didn't make that clear before, but that is really the goal.
  • We had decided that some form of the following code is bad.

    die1 = rand_r(&seed1) % die1Sides + 1; 

  • We need to keep track of 2 - 3 variables.
  • We need to not mistype the equation
  • And it most likely breaks cohesion, as this is a low level detail
• write a struct that holds the die
  • What is the syntax of a struct?
  • Take a look at the reference at https://en.cppreference.com/w/c/language/struct.html
  • Discussed on page 23 of the book.
  • What do we use a struct for?
    • "... structs are not typically used for OO programming in C++..."
  • Do we have a naming convention for a struct?
• As far as I can see, we have three fields associated with a die
  • The number of sides
  • The seed
  • The current value.
• So the struct

  • struct DieT {
        int sides{6};
        unsigned int seed{1};
        int value;
    }; 

  • This assumes that the most common die is 6 sided.
• How do i
  • Declare a die?
  • Set the sides of a die?
  • print the value of a die?
• Our code should become something like task3pre.cpp.
  • Do you understand all of this code?
• There are some parts that bother me.
  • Initializing the die
    • The value should be set based on the seed, but it is not.
    • An programmer might use a 0 for the value of the die.
    • The seed is set to 1, but I need to remember

      die1.seed = static_cast(rand()); 

  • Rolling the die is messy
• Could we clean this up with some functions?
  • Initialize a die
  • Roll a die
  • Get the value of a die
  • Get the number of sides of a die.
• You might not like the last two, but live with it for now.
• Take a look at task3Bpre.cpp
• Next let's implement a game with this die.