9

FORGE

for further details on how we put this together and
connected it to the Arduino.
The inspiration for this project comes directly
from our previous tutorials, where we used the
screen to show a sideways-scrolling representation
of changes in temperature over time. Sideways-
scrolling backgrounds like this are a traditional game

mechanic, used in classics like the original Defender
from 1979/1980, and Super Mario Bros. But the
game we’re most inspired by for this project is called
Scramble, from 1981. In Scramble you needed to fly
your ship across a cityscape before entering a series
of tunnels. These tunnels became a mini game in
their own right as you tried to position your ship in
the best part of the screen to navigate impossible
turns and an ever-decreasing tunnel height. It’s this
part of Scramble we’re going to loosely emulate
with our own Arduino game, adapting the scrolling
temperature chart we’ve already created into a
tunnel. But to start with, we need to get the joystick
controls working, and for that we need to be able
see (and control) something on the screen.

SHIP SHAPE
Many of the earliest games used simple geometry
to represent a spaceship. One of the best known is
Asteroids, which used an augmented triangle as the

main craft for the player to control, with degrees of

rotation and thrust. This was because the screen

used a ‘vector’ display that could only draw lines

from one point to another. We haven’t suffered the

same restrictions since raster-scanning cathode ray

tubes became commonplace, and flatscreen modern

technology made it all but a distant memory. But

vectors like these are still used when you want an

image to scale, or when you don’t have the memory

for more than two colours, and they’re the basis for

modern scalable graphics like SVG and 3D polygons.

Thanks to the Adafruit graphics library, it only takes

a single command to draw a

triangle (or a rectangle,

or a circle – filled or

empty), and we’ll

revisit the idea when

adding some stars

to our game. But for

now, we’re going

to use a bitmap for

the ship, another

Many of the earliest games

used simple geometry to

represent a spaceship. One of

the best known is Asteroids,

which used an augmented

triangle as the main craft

”

”

PICKING A BOARD

MEMORY

ARDUINO TYPE

Duemilanove (2009) UNO Rev3 Mega Mega 2560

Flash 16 kBytes 32 kBytes 128 kBytes 256 kBytes

SRAM 1024 bytes 2048 bytes 8 kBytes 8 kBytes

Below

The KY-023 module

uses a joystick

very similar to

a PlayStation 2

controller joystick,

which can also be

extracted and used in

the same way

Left

One of the main

differences between

each version of the

Arduino hardware is

the amounts of both

flash memory and

SRAM available