Version aq: mouse wheel support

I've been focusing so much on the mobile/touchscreen experience that I forgot to wire up the mouse wheel. This omission is now fixed, along with a minor bugfix and a few more abbreviations (example 7). Thanks to LÖVE Forum user milon for reminding me of this.

This might also be a good time to share a couple of programs I've been building using Lua Carousel over the past week. As you copy them and paste them in, remember to load the abbreviations before running them.

A hilbert curve

x,y = 0,700
dirx,diry = 1,0
n = 10
g.setLineWidth(3)
color(1,0,1, 0.1)
function draw_lsys(s)
  for i=1,#s do
    local c = s:sub(i,i)
    if c == 'F' then
      forward()
    elseif c == '+' then
      left()
    elseif c == '-' then
      right()
    end
  end
end
function forward()
  local x2 = x+dirx*n
  local y2 = y+diry*n
  line(x,y, x2,y2)
  x,y = x2,y2
end
function left()
  if dirx == 0 then
    dirx = diry
    diry = 0
  else
    diry = -dirx
    dirx = 0
  end end
function right()
  if dirx == 0 then
    dirx = -diry
    diry = 0
  else
    diry = dirx
    dirx = 0
  end end
function lsys(s)
  local result = {}
  for i=1,#s do
    local c = s:sub(i,i)
    if c == 'A' then
      table.insert(result, '+BF-AFA-FB+')
    elseif c == 'B' then
      table.insert(result, '-AF+BFB+FA-')
    else
      table.insert(result, c)
    end
  end
  return table.concat(result)
end
s = 'A'
for _ = 1,5 do
  s = lsys(s)
end
draw_lsys(s)

A tree fractal

Iters = 7
Zoom = 10
X0 = Safe_width*3/4
Y0 = Safe_height-10
N = Safe_height/2/Iters/Zoom
Left = -0.3
Right = 0.7
function car.draw()
  x,y = X0,Y0
  Angle = -pi/2
  Stack = {}
  color(1,0,1, 0.4)
  s = '0'
  for _ = 1,Iters do
    s = lsys(s)
  end
  --print(s)
  draw_lsys(s)
end
function draw_lsys(s)
  for i=1,#s do
    local c = s:sub(i,i)
    if c == '0' or c == '1' then
      forward()
    elseif c == '[' then
      push()
    elseif c == ']' then
      pop()
    end
  end
end
function forward()
  local x2 = x + N*cos(Angle)
  local y2 = y + N*sin(Angle)
  line(x,y, x2, y2)
  --print('|', x,y, x2,y2)
  x, y = x2, y2
end
function push()
  table.insert(Stack, {x, y, Angle})
  Angle = Angle+Left
  --print('[', x,y, Angle)
end
function pop()
  x,y, Angle = unpack(Stack[#Stack])
  table.remove(Stack)
  Angle = Angle+Right
  --print(']', x,y, Angle)
end
function lsys(s)
  local result = {}
  for i=1,#s do
    local c = s:sub(i,i)
    if c == '1' then
      table.insert(result, '11')
    elseif c == '0' then
      table.insert(result, '1[0]0')
    else
      table.insert(result, c)
    end
  end
  return table.concat(result)
end
function car.mouse_press(x,y, b)
  --X0,Y0 = x,y
  Left = -x/Safe_width
  Right = y/Safe_height
end
function car.mouse_wheel_move(dx,dy)
    Iters = Iters+dy
    Iters = math.max(Iters, 1)
    Iters = math.min(Iters, 12)
    N = Safe_height/2/Iters/Zoom
end

To connect up with the start of this post, try hiding the editors and then moving the mouse wheel on the tree fractal.