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4.2. Manifest constants

The constant MAX_PARAM defines the maximum value for a color parameter. For example, black is represented as the triple (0,0,0), while white is represented as (65535,65535,65535).

# Manifest constants

MAX_PARAM  =  65535

The constant N_PARAMS is the number of parameters in a color model. This will always be three, but we use a manifest constant so that readers will not have to look at a literal “3” and try to figure out three of what.

N_PARAMS  =  3

The constant MAX_BYTE is the largest number that can be stored in a byte as an unsigned integer.

MAX_BYTE  =  255

Also global are the names of the fonts used throughout the application. BUTTON_FONT is used more or less everywhere; MONO_FONT is used where a monospaced font is required.

BUTTON_FONT  =  ('times', 12)
MONO_FONT  =  ('lucidatypewriter', 14, 'bold')