Programming Web Graphics with Perl and GNU Softwar

Colors in GIFgraph

All GIFgraph color routines taking colorname as a parameter expect a string with the name of a valid color. GIFgraph comes bundled with the GIFgraph::colour^[15] package that provides some methods for organizing and manipulating colorname strings. GIFgraph has 29 predefined colorname strings (see Table 6.2); you can define additional strings in an external file by using the read_rgb( )method.

Table 6-2. Predefined GIFgraph Color Names and Numerical Representations

Color Name String	Red	Green	Blue	Hex Representation
white	255	255	255	#FFFFFF
lyellow	255	255	0	#FFFF00
gold	255	215	0	#FFD700
cyan	0	255	255	#00FFFF
pink	255	183	193	#FFB7C1
lgray	191	191	191	#BFBFBF
lorange	255	183	0	#FFB700
lbrown	210	180	140	#D2B48C
lgreen	0	255	0	#00FF00
yellow	191	191	0	#BFBF00
orange	255	127	0	#FF7F00
dpink	255	105	180	#FF69B4
green	0	191	0	#00BF00
marine	127	127	255	#7F7FFF
gray	127	127	127	#7F7F7F
dyellow	127	127	0	#7F7F00
dgreen	0	127	0	#007F00
lpurple	255	0	255	#FF00FF
dbrown	165	42	42	#A52A2A
dgray	63	63	63	#3F3F3F
purple	191	0	191	#BF00BF
lred	255	0	0	#FF0000
red	191	0	0	#BF0000
dpurple	127	0	127	#7F007F
dred	127	0	0	#7F0000
lblue	0	0	255	#0000FF
blue	0	0	191	#0000BF
dblue	0	0	127	#00007F
black	0	0	0	#000000

Calling the usemethod with the :colourstags will import the _rgb( ), _hue( ), and _luminance() functions. The :lists ...