digital literacy for everyone



[lit] fig is a multi-purpose educational language-- graphics output is one of the functions it demonstrates. the language was originally designed to offer 16 colours in the term window or vt, with a compatible 16-colour palette in a graphics window. in 2017, i decided that rather than extend the language, a simple function (rgbcolour) would allow 24-bit colour without any change to the language itself. vsine is one of the early programs that use this function. [img][img] [fig] #### license: creative commons cc0 1.0 (public domain) #### proginf = "v sine 2017 mn" function rgbcolour r g b c python figcgapal[c] = (r, g, b) fig fig v 1 c 400 w 3.14159 divby 2 for r 490 175 -.125 e w minus 0.00413367105263 swap e w # 3.14159 / 4 / (490 - 300) for p -3.14159 3.14159 .003067958984375 t w cos times 380 divby 2 int rc r divby 2.5 int rd 256 minus rc rgbcolour rc rc 32 11 e w sin times t times 2 plus r plus 7 divby 5 x p times 2 cos times e plus c int y p times 2 sin times e plus r minus 50 int m 6.28 plus 1.57 divby 108.503 divby 2 now v plus m swap now v rc r divby 4 int mod 2 iftrue rc now v int mod 2 times 11 pset x y now y2 y minus 1 pset x y2 now fig next now display next now display lineinput
fig main page: [url][url] home: [lit][lit]