Intro. to Game Programming

Want to program a game?

Very Important Points

• Classroom etiquette• Lab etiquette• Problems with – Teacher– Course content (Course Outline)– Evaluation– Programming for labs– Personal

Basics

• Game Consoles and mobile devices• Hardware, Software and Firmware• 1’s and 0’s• Assembly Language• HLL (High Level Language)

Game Consoles and Mobile

• All game machines share their internals with regular computer architecture

• All game machines have– Input– Output– Processing

Hardware, Software & Firmware

• Hardware refers to a PHYSICAL DEVICE• Software refers to INFORMATION that

commands a device• Firmware refers to EMBEDDED Software –

fixed INSIDE a device

Processing

• Game consoles have microprocessors that understand and perform operations based on a PATTERN of 1’s and 0’s

1’s and 0’s

• Can be COMMANDS (or INSTRUCTIONS) to a device

• Can be DATA for use by a device• Determination of interpretation depends on

the CONTEXT of the 1s and 0s

Machine Code

• Jumping to the address 1024:[ op | target address ] 2 1024 decimal000010 00000 00000 00000 10000 000000

binary

Assembly Code• MOV r0, #0C ;load base address of string into r0

LOAD: MOV r1,(r0) ;load contents into r1CALL PRINT ; call a print routine to print the character in r1INC r0 ;point to next characterJMP LOAD ;load next character

• ALMOST ENGLISH

High Level Language

• Early HLL – Fortran – Cobol• Basic• Pascal• C (from B) Jumping to the address 1024:• C++• Java

Why C++?

• Industry Standard• 70% of Game Developers use this language on

a DAILY basis• Object-oriented• Practical outside of game development in

industry

How do we make a program?

• Compile• Link• Load

COMPILE

• Command Line

cc -c file.c

• GUI (Graphical User Interface)

Go to menu option… Build and select Compile

COMPILE (More)

• Compiling takes English-like language and creates instructions that the computer can follow.

• Calls to other code will be links and need to be resolved in order to build REAL executable 1’s and 0’s

LINK and LOAD

• Command Line

ln file1.o file2.o

• GUI (Graphical User Interface)

Go to menu option… Build and select BUILD

LINK and LOAD (More)

• All calls to other code are resolved into actual locations where the code is now residing.

• Programmers use libraries that contain many commonly requested functions. These are resolved in the LINK and LOAD process as well

• The LOAD process refers to the first part of executing (or running) the program on a computer.

Hello World in C++#include <iostream>

using namespace std;

int main(){ cout << “Hello World" << endl; return 0;}

Hello World in C++

#include <iostream>

• Preprocessor command – starts with ‘#’ • Processed BEFORE actual compile• Effect of including an entire file inside your file

Hello World in C++

using namespace std;

• Declares where to assume you are “using” functions

• “std” means STANDARD and allows a command like “cout” to be understood

Hello World in C++

int main(){}• A function called “main” which returns an “int”

value• “main” MUST be in all C++ programs• “{“ “}” delimit the function (indicate what is

inside the function)

Hello World in C++

cout << “Hello World" << endl;• “cout” is an object that is connected to our

terminal screen by default• “Hello World” is sent to the object for display

on the screen• “endl” is a “manipulator” that adds a

CR LF (Carriage Return and Line Feed)

Compiling Hello World in C++

• Save the contents of the program into a file called “hello.cpp”

• Run the following command

c++ -o hello hello.cpp

• The PROGRAM is created… linking and loading is ALSO performed (by default)

Running the Hello World Program

• In a Unix/MacOS/Linux environment

./hello

• In Windows… the program MUST be named with “.exe” on the end

hello.exe