Löve2d code for loading and drawing a tetured polygon

gistfile1.lua

function love.load()
  -- Load our repeating texture
  local img      = love.graphics.newImage("dirt.png")

  -- Points for our polygon
  local vertices = {12,0, 396,7, 500,375, 195,520, 78,377}
  
  texturedPoly = newTexturedPoly(vertices, img)
end

function newTexturedPoly(vertices, img)
  -- We want our images to tile
  img:setWrap("repeat", "repeat")

  -- We need a quad so the img is repeated
  -- The quad width/height should be the max x/y of the poly
  local quad = love.graphics.newQuad(0, 0, 500, 520, img:getWidth(), img:getHeight())

  -- Set up and store our clipped canvas once as it's expensive
  local canvas = love.graphics.newCanvas()

  love.graphics.setCanvas(canvas)

  -- Our clipping function, we want to render within a polygon shape
  local myStencilFunction = function()
    love.graphics.polygon("fill", unpack(vertices))
  end
  love.graphics.setStencil(myStencilFunction)
  
  -- Setting to premultiplied means that pixels just get overlaid ignoring
  -- their alpha values. Then when we render this canvas object itself, we
  -- will use the alpha of the canvas itself
  love.graphics.setBlendMode("premultiplied")

  -- Draw the repeating image within the quad
  love.graphics.drawq(img, quad, 0, 0)

  -- Reset everything back to normal
  love.graphics.setBlendMode("alpha")
  love.graphics.setStencil()
  love.graphics.setCanvas()
  
  return canvas
end

function love.draw()
  -- Draw our canvas object texturedPoly
  love.graphics.draw(texturedPoly, 50, 50)

  -- showfps
  love.graphics.setColor(255,255,255,200)
  love.graphics.print(tostring(love.timer.getFPS()), love.graphics.getWidth()-30, love.graphics.getHeight()-20)
end