Ergonomics - iPhone Game Blueprints - page 70

form of color vision weakness and a camera with the specific color filter will start im-
mediately. The main advantage of this way of simulation is the opportunity to test not
static images, but the dynamic gameplay itself.
There are a lot of online tools that let you upload images and look at their color
transformation. For instance, look at the inclusive design toolkit, which was deve-
loped by the University of Cambridge, Engineering Design Center and sponsored
by BT. Its goal is to let designers produce solutions for a wide range of customers,
which include those with a number of abilities and also those with some special
needs. The online simulator can be found at http://www.inclusivedesigntoolkit.com/
betterdesign2/simsoftware/simsoftware.html . It shows examples of vision affected
not only by color blindness, but also by cataracts, glaucoma, diabetic retinopathy,
and so on.
Look at your game screen through the simulator and try to determine all the weak
points you've got. Don't think much about the background artwork or other elements
of decoration, they will not confuse a player with a color vision weakness; try to fix
all game items that have visual coding based on colors (primarily all the red/green
pairs, then blue/violet, and so on). If the game element uses only a few color signals
to demonstrate its state, the solution is simple: contradictory colors may be replaced
with more secure ones. For example, a red signal can be replaced with a yellow,
and a green with a blue. It is useful to use special color palettes full of reliable color
swatches.
You can find some of the palettes on the website of Christine Rigden at ht-
tp://www.rigdenage.co.uk/safecolours/palettefiles.html . She was the author of the in-
teresting article The Eye of the Beholder—Designing for Colour-Blind Users pub-
lished in British Telecommunications Engineering, Vol. 17 , in January 1999. One of
the ideas described in the article was the creation of special safe palettes for color
blind people, based on the web-safe color palette. The result is presented in the form
of color tables suitable for Adobe Photoshop.
In case the game has game triggers with a lot of color states (for instance, it is a
puzzle with a dozen color balls), another approach can be used. Each trigger can
feature a special graphic icon, which helps to differentiate it from others. There are a
lot of familiar examples from real life using such a method to distinguish objects. For
example, playing cards, which have both colors and symbols; traffic lights for pedes-
trians, where special pictograms (or words) are used (the green light usually displays
the symbol of a walking person, but the red light shows a person standing still). So