Fish eye forest from above - codea lua

--# Main
displayMode(FULLSCREEN)
supportedOrientations(PORTRAIT)

function setup()
    print("Hello World!")
    t=Trees()
    mx = 0
    my = 0
    lt = ElapsedTime
end

function draw()
    background(25, 32, 26, 255)
    t:draw()
    t:move(mx,my)
    fill(195, 39, 39, 255)
    --text(1/(ElapsedTime - lt),100,100)
    lt = ElapsedTime
end

function touched(touch)
    if touch.state == BEGAN then
        if touch.x > WIDTH/2 + WIDTH/4 then
            mx = mx - 1
        elseif touch.x < WIDTH/2 - WIDTH/4 then
            mx = mx + 1
        end
        if touch.y > HEIGHT/2 + HEIGHT/4 then
            my = my - 1
        elseif touch.y < HEIGHT/2 - HEIGHT/4 then
            my = my + 1
        end
    end
end
--# Tree
Tree = class()

function Tree:init()
    self.x = math.random(WIDTH+200)-100
    self.y = math.random(HEIGHT+200)
    self.tl = 16
    self.tw = 8
    self.tb = self.tw * 1.2
    self.lw = 32
end

function Tree:drawTrunk()
    stroke(125, 81, 37, 255)
    fill(125, 81, 37, 255)
    strokeWidth(self.tw)
    local v1 = vec2(self.x,self.y)
    local v2 = vec2(WIDTH/2,HEIGHT/2)
    local v3 = v2 - v1
    local v4 = v3:normalize()
    local d = v1:dist(v2)
    local ttx = self.x-(v4.x*(d/self.tl))
    local tty = self.y-(v4.y*(d/self.tl))
    line(self.x,self.y,ttx,tty)
    ellipse(self.x,self.y,self.tb,self.tb)
end

function Tree:drawLeaves()
    noStroke()
    fill(39, 133, 29, 127 + 64)
    local v1 = vec2(self.x,self.y)
    local v2 = vec2(WIDTH/2,HEIGHT/2)
    local v3 = v2 - v1
    local v4 = v3:normalize()
    local d = v1:dist(v2)
    local ttx = self.x-(v4.x*(d/self.tl))
    local tty = self.y-(v4.y*(d/self.tl))

    ellipse(ttx,tty,self.lw,self.lw)

end

--# Trees
Trees = class()

function Trees:init(n)
    if n == nil then self.n = 128 else self.n = n end
    self.t = {}
    for i = 1, self.n do
        self.t[i] = Tree()
    end
end

function Trees:draw()
    for i = 1, self.n do
        self.t[i]:drawTrunk()
    end
    for i = 1, self.n do
        self.t[i]:drawLeaves()
    end

end

function Trees:move(x,y)
    for i = 1, self.n do
        self.t[i].x = self.t[i].x + x
        self.t[i].y = self.t[i].y + y
        if self.t[i].y < -100 then
            self.t[i].x = math.random(WIDTH+200)-100
            self.t[i].y = HEIGHT + 100
        elseif self.t[i].y > HEIGHT + 100 then
            self.t[i].x = math.random(WIDTH+200)-100
            self.t[i].y = -100
        elseif self.t[i].x < -100 then
            self.t[i].y = math.random(HEIGHT+200)-100
            self.t[i].x = WIDTH + 100
        elseif self.t[i].x > WIDTH + 100 then
            self.t[i].y = math.random(HEIGHT+200)-100
            self.t[i].x = -100
        end
    end
end