Color wheel: Difference between revisions

=={{header|Lua}}==

{{libheader|LÖVE}}

<lang Lua>

local function hsv_to_rgb (h, s, v) -- values in ranges: [0, 360], [0, 1], [0, 1]

local r = math.min (math.max (3*math.abs (((h )/180)%2-1)-1, 0), 1)

local g = math.min (math.max (3*math.abs (((h -120)/180)%2-1)-1, 0), 1)

local b = math.min (math.max (3*math.abs (((h +120)/180)%2-1)-1, 0), 1)

local k1 = v*(1-s)

local k2 = v - k1

return k1+k2*r, k1+k2*g, k1+k2*b -- values in ranges: [0, 1], [0, 1], [0, 1]

end

function love.load()

local w, h, r = 256, 256, 128

local cx, cy = w/2+0.5, h/2+0.5

canvas = love.graphics.newCanvas ()

love.graphics.setCanvas(canvas)

for x = 0, w do

for y = 0, h do

local dx, dy = x-cx, y-cy

if dx*dx + dy*dy <= r*r then

local h = math.deg(math.atan2(dy, dx))

local s = (dx*dx + dy*dy)^0.5/r

local v = 1

love.graphics.setColor (hsv_to_rgb (h, s, v))

love.graphics.points (x, y)

end

end

end

love.graphics.setCanvas()

end

function love.draw()

love.graphics.setColor (1,1,1)

love.graphics.draw (canvas)

end

</lang>