local mask = love.graphics.newImage("wwe.png")

local mask_shader = love.graphics.newShader[[
   vec4 effect(vec4 color, Image texture, vec2 texture_coords, vec2 screen_coords) {
      if (Texel(texture, texture_coords).rgb == vec3(0.0)) {
         // a discarded pixel wont be applied as the stencil.
         discard;
      }
      return vec4(1.0);
   }
]]

function love.load()
  local canvas = love.graphics.newCanvas(20, 20)
  love.graphics.setCanvas(canvas)
        love.graphics.clear()
        love.graphics.setBlendMode("alpha")
        love.graphics.setColor(1, 1, 1, 0.8)
        love.graphics.circle('fill', 10, 10, 5)
  love.graphics.setCanvas()
  psystem = love.graphics.newParticleSystem(canvas, 1000)
  psystem:setParticleLifetime(2, 8)
  psystem:setEmissionRate(60)
  psystem:setSizeVariation(0.7)
  psystem:setSpeed(5)
  --psystem:setLinearAcceleration(-40, -40, 40, 0)
  psystem:setRadialAcceleration(4,8)
  psystem:setEmissionArea('borderrectangle', 150, 10, 0, false)
  psystem:setColors(
     1,0.35,0,1,
     0.85,  0.85, 0.85, 0
     )
end

local function myStencilFunction()
   love.graphics.setShader(mask_shader)
   love.graphics.draw(mask, 0, 0)
   love.graphics.setShader()
end

function love.draw()
   love.graphics.stencil(myStencilFunction, "increment")
   --love.graphics.setStencilTest("less", 1)
   love.graphics.draw(psystem, love.graphics.getWidth() * 0.5, love.graphics.getHeight() * 0.5)
   love.graphics.setStencilTest()
end

function love.update(dt)
  psystem:update(dt)
end