모듈:사용자:Darkbosal/HSV

local p = {}

function rgb2hsv(r, g, b)

local max = math.max(r, g, b)

local min = math.min(r, g, b)

local c = max - min

-- calculate hue

local h

if c == 0 then

h = 0

elseif max == r then

h = 60 * (0 + ((g - b)/c))

elseif max == g then

h = 60 * (2 + ((b - r)/c))

elseif max == b then

h = 60 * (4 + ((r - g)/c))

end

if h < 0 then h = h + 360 end

-- calculate value

local v = max

-- calculate luminance

-- local l = (max + min) / 2

-- calculate saturation

local s

if c == 0 then

s = 0

else

s = c/v

end

return h, s, v
end

function hsv2rgb(h, s, v)

local hi = math.floor(h / 60)

local f = ((h / 60) - hi)

local p = v * (1 - s)

local q = v * (1 - s * f)

local t = v * (1 - s * (1 - f))

if hi == 1 then

return q, v, p

elseif hi == 2 then

return p, v, t

elseif hi == 3 then

return p, q, v

elseif hi == 4 then

return t, p, v

elseif hi == 5 then

return v, p, q

else

return v, t, p

end

end

function decodeRGBHex(rgb)

local r = string.sub(rgb, 1, 2)

local g = string.sub(rgb, 3, 4)

local b = string.sub(rgb, 5, 6)

return tonumber(r, 16), tonumber(g, 16), tonumber(b, 16)

end

function getRGB(args)

local r, g, b, i

if string.len(args[1]) == 6 then

r, g, b = decodeRGBHex(args[1])

i = 2

else

r = args[1]

g = args[2]

b = args[3]

i = 4

end

return r / 255, g / 255, b / 255, i

end

--[[toHSV
Description: Converts a RGB color to a HSV color.

Usage: or

Output: hue [0°..360°]/saturation [0..1]/value [0..1]
]]
function p.toHSV(frame)

local r, g, b = getRGB(frame.args)

local h, s, v = rgb2hsv(r, g, b)

return h .. "/" .. s .. "/" .. v

end

--[[hue
Description: Returns the hue of a RGB color.

Usage: or

Output: hue [0°..360°]
]]
function p.hue(frame)

local r, g, b = getRGB(frame.args)

local h, s, v = rgb2hsv(r, g, b)

return h

end

--[[saturation
Description: Returns the saturation of a RGB color.

Usage: or

Output: saturation [0..1]
]]
function p.saturation(frame)

local r, g, b = getRGB(frame.args)

local h, s, v = rgb2hsv(r, g, b)

return s

end

--[[value
Description: Returns the hue of a RGB color.

Usage: or

Output: value [0..1]
]]
function p.value(frame)

local r, g, b = getRGB(frame.args)

local h, s, v = rgb2hsv(r, g, b)

return v

end

--[[saturate
Description: Saturates a RGB color by a given factor.

Usage: or
Optionally "factor" can be followed by another parameter with the value "hex" can be given to return the RGB color in a hexadecimal representation.

Output: saturated RGB
]]
function p.saturate(frame)

local r, g, b, i = getRGB(frame.args)

-- convert to HSV

local h, s, v = rgb2hsv(r, g, b)

-- saturate

s = s * frame.args[i]

if s < 0 then

s = 0

elseif s > 1 then

s = 1

end

-- convert back to RGB

local r, g, b = hsv2rgb(h, s, v)

r = math.floor(r * 255 + 0.5)

g = math.floor(g * 255 + 0.5)

b = math.floor(b * 255 + 0.5)

-- return values

if frame.args[i + 1] == "hex" then

return string.format("%.2X%.2X%.2X", r, g, b)

else

return r .. "/" .. g .. "/" .. b

end

end

--[[toRGB
Description: Converts a HSV color to a RGB color.

Usage: with H in [0°..360°], S in [0..1] and V in [0..1].
Optionally a 4th parameter with the value "hex" can be given to return the RGB color in a hexadecimal representation.

Output: R/G/B
]]
function p.toRGB(frame)

local r, g, b = hsv2rgb(frame.args[1], frame.args[2], frame.args[3])

-- transform from real [0..1] to integer [0..255]

r = math.floor(r * 255 + 0.5)

g = math.floor(g * 255 + 0.5)

b = math.floor(b * 255 + 0.5)

-- return values

if frame.args[4] == "hex" then

return string.format("%.2X%.2X%.2X", r, g, b)

else

return r .. "/" .. g .. "/" .. b

end

end

return p