70 lines
1.8 KiB
Lua
Executable File

#!/usr/bin/env lua
-- a cgi script that draws an analog clock with lua and lua-gd
-- (c) 2004 Alexandre Erwin Ittner
-- $Id: clock.lua,v 1.16 2005/03/06 01:32:35 dermeister Exp $
require "gd"
function createClock(size, hours, minutes)
local im = gd.createTrueColor(size, size)
local white = im:colorAllocate(255, 255, 255)
local gray = im:colorAllocate(128, 128, 128)
local black = im:colorAllocate(0, 0, 0)
local blue = im:colorAllocate(0, 0, 128)
local cxy = size/2
im:filledRectangle(0, 0, size, size, white)
im:setThickness(math.max(1, size/100))
im:arc(cxy, cxy, size, size, 0, 360, black)
local ang = 0
local rang, gsize
while ang < 360 do
rang = math.rad(ang)
if math.mod(ang, 90) == 0 then
gsize = 0.75
else
gsize = 0.85
end
im:line(
cxy + gsize * cxy * math.sin(rang),
size - (cxy + gsize * cxy * math.cos(rang)),
cxy + cxy * 0.9 * math.sin(rang),
size - (cxy + cxy * 0.9 * math.cos(rang)),
gray)
ang = ang + 30
end
im:setThickness(math.max(1, size/50))
im:line(cxy, cxy,
cxy + 0.45 * size * math.sin(math.rad(6*minutes)),
size - (cxy + 0.45 * size * math.cos(math.rad(6*minutes))),
blue)
im:setThickness(math.max(1, size/25))
rang = math.rad(30*hours + minutes/2)
im:line(cxy, cxy,
cxy + 0.25 * size * math.sin(rang),
size - (cxy + 0.25 * size * math.cos(rang)),
blue)
im:setThickness(1)
local sp = math.max(1, size/20)
im:filledArc(cxy, cxy, sp, sp, 0, 360, black, gd.ARC)
return im
end
dh = os.date("*t")
im = createClock(100, dh.hour, dh.min)
print("Content-type: image/png")
print("Refresh: 60") -- Ask browser to reload the image after 60s
print("Pragma: no-cache") -- Can mozilla understand this?
print("Expires: Thu Jan 01 00:00:00 UTC 1970") -- Marks as expired
print("")
io.write(im:pngStr())