-- Textured Polygon Demo
-- request love2d 11.3
--
-- Original xXxMoNkEyMaNxXx
-- fork drunken_munki
-- fork mieki256

function love.load()
  tp = require 'Perspective'

  love.graphics.setDefaultFilter("linear", "linear", 2)

  img = love.graphics.newImage('textures/uvcheckermap01-512.png')
  -- img = love.graphics.newImage('textures/ff nub.png')
  -- img = love.graphics.newImage('textures/lenaC.jpg')

  vert = {{100, 100}, {400, 100}, {400, 400}, {100, 400}}

  -- Try uncommenting one of these! 600 is the image size.--
  -- tp:setRepeat({0.25,0.25},{0.75,0.75})
  -- tp:setRepeat({253/600,50/600},{80/600,80/600})

  -- Dragging Vertices & Colour (for demonstration purposes)--
  love.graphics.setBackgroundColor(0.2, 0.2, 1, 1)

  dragging = nil
  offset = {0, 0}
  rgba = {1, 1, 1, 1}
end

function love.update(dt)
  -- drag vertex
  local x, y = love.mouse.getPosition()
  local b1d = love.mouse.isDown(1)

  if dragging then
    vert[dragging][1] = x + offset[1]
    vert[dragging][2] = y + offset[2]
    if not b1d then dragging = nil end
  elseif b1d then
    local vc
    local best = math.huge
    for i, v in next, vert do
      local dis = math.sqrt((v[1] - x) ^ 2 + (v[2] - y) ^ 2)
      if dis < best then vc, best = i, dis end
    end
    dragging = vc
    offset[1] = vert[vc][1] - x
    offset[2] = vert[vc][2] - y
  end

  -- change color
  local t = love.timer.getTime() % math.pi
  rgba[1] = math.sin(t) ^ 2
  rgba[2] = math.sin(t + math.pi / 3) ^ 2
  rgba[3] = math.sin(t + 2 * math.pi / 3) ^ 2
  rgba[4] = math.cos(love.timer.getTime() * 2 ^ 0.5) ^ 2
end

function love.draw()
  -- Yep, that's it!
  love.graphics.setColor(rgba[1], rgba[2], rgba[3], rgba[4])
  tp:quad(img, vert[1], vert[2], vert[3], vert[4])

  love.graphics.setColor(1, 1, 1, 1)
  love.graphics.print("FPS: " .. love.timer.getFPS(), 8, 8)
end

function love.keypressed(key, isrepeat)
  -- ESC to exit
  if key == "escape" then love.event.quit() end
end