flag.lua

love.graphics.setDefaultFilter("linear", "linear", 16)

function love.load()
  love.window.setMode(800, 600, { msaa = 0 })
end

local triCanvas = love.graphics.newCanvas(2*1792, 2*828, { msaa = 8 })
local function mkCanvas()
  triCanvas:clear()
end

local variance = 0.1
local function uvColor(u, v)
  math.randomseed(u*500 + v)
  local clkSpdR = math.random(5, 10)
  -- local clkSpdG = math.random(5, 10)
  -- local clkSpdB = math.random(5, 10)
  local clkOffR = math.random(0, 50)
  -- local clkOffG = math.random(0, 50)
  -- local clkOffB = math.random(0, 50)

  local colA = { 85/255, 205/255, 252/255 }
  local colB = { 1, 1, 1 }
  local colC = { 247/255, 168/255, 184/255 }
  local pat = { colA, colC, colB, colC, colA }

  -- local r, g, b = u, v, 0.5
  local idx = math.ceil(v * #pat)
  -- print(v)
  if idx == 0 then idx = 1 end
  if idx > #pat then idx = #pat end
  local r, g, b = unpack(pat[idx])

  -- P | B | W | B | P
  local statVar = variance*math.sin(3*clkSpdR*os.clock() + clkOffR)
  -- return {r + variance*math.sin(10*clkSpdR*os.clock() + clkOffR), g + variance*math.sin(10*clkSpdG*os.clock() + clkOffG), b + variance*math.sin(10*clkSpdB*os.clock() + clkOffB)}
  return {r + statVar, g + statVar, b + statVar}
end

local triHeight = (math.sqrt(3)/2)*50
local width = 1792*2/50 + 10--32
local height = 828*2/triHeight + 5

function love.draw() 
  love.graphics.setCanvas(triCanvas)
  do
    love.graphics.clear()
    -- love.graphics.setLineStyle("smooth")
    -- love.graphics.setLineWidth(10)
    -- love.graphics.polygon("fill", 0, 0, 50, 0, 25, (math.sqrt(3)/2)*50)


    for x = 0, width do
      for y = 0, height do
        local cx, cy = x / width, y / height
        love.graphics.setColor(uvColor(cx, cy))

        local yOff = ((y / 4) % 1)

        if y % 2 == 0 then
          local yTri = (y / 2)*triHeight
          -- love.graphics.setColor({1, 1, 1})
          love.graphics.polygon("fill", (x - yOff)*50, yTri, ((x - yOff) + 1)*50, yTri, (x - yOff)*50 + 25, yTri + triHeight)
        else
          local yTri = ((y - 1) / 2)*triHeight
          local xSha = (x + yOff - 0.75)
          -- love.graphics.setColor({0.5, 0.5, 0.5})
          love.graphics.polygon("fill", xSha*50, yTri + triHeight, (xSha + 1)*50, yTri + triHeight, xSha*50 + 25, yTri)
        end
      end
    end
    -- love.graphics.polygon("line", 0, 0, 2*50, 0, 2*25, 2*(math.sqrt(3)/2)*50)
  end
  love.graphics.setCanvas()

  love.graphics.setColor({1, 1, 1})
  love.graphics.draw(triCanvas, 0, 0, 0, 0.5)
end

function love.keypressed(k)
  if k == "up" then
    height = height - 1
  elseif k == "down" then
    height = height + 1
  elseif k == "s" then
    triCanvas:newImageData():encode("png", "tri-" .. math.random(0, 100000000) .. ".png")
  end

  print(height)
end