mtpaint/init.lua

paint = {}
paint.loopmax=50
paint.loops=0

minetest.register_alias("pencil", "mtpaint:pencil")
minetest.register_alias("fill", "mtpaint:fill")
minetest.register_alias("bucket", "mtpaint:fill")
minetest.register_alias("eraser", "mtpaint:eraser")
minetest.register_alias("gum", "mtpaint:eraser")
minetest.register_alias("picker", "mtpaint:picker")
minetest.register_alias("colorpicker", "mtpaint:picker")
minetest.register_alias("nodepicker", "mtpaint:picker")

--function

paint.has_air = function(pos)
  print("check for air")
  for i=-1,1,2 do
    local p = {x=pos.x+i, y=pos.y, z=pos.z}
    local n = minetest.env:get_node(p).name
    print(n)
    if minetest.registered_nodes[n].walkable == false then
      return true
    end
  end
  for i=-1,1,2 do
    local p = {x=pos.x, y=pos.y+i, z=pos.z}
    local n = minetest.env:get_node(p).name
    print(n)
    if minetest.registered_nodes[n].walkable == false then
      return true
    end
  end
  for i=-1,1,2 do
    local p = {x=pos.x, y=pos.y, z=pos.z+i}
    local n = minetest.env:get_node(p).name
    print(n)
    if minetest.registered_nodes[n].walkable == false then
      return true
    end
  end
  print("doesnothaveair")
  return false
end

paint.replace = function(user, position, replace, replacer, full)
  
  if not minetest.registered_nodes[replacer] then return end
  if replace == replacer then return end
  if paint.loops > 2000 then return end
  local pos = position
  if full == false then
   if paint.has_air(pos) == false then return end
  end
  paint.loops = paint.loops + 1

  local node = replacer
  
  minetest.env:set_node(pos,{name=node})
    
  for i=-1,1,2 do
    local p = {x=pos.x+i, y=pos.y, z=pos.z}
    local n = minetest.env:get_node(p).name
    if n == replace then
      minetest.env:set_node(pos,{name=node})
      paint.replace(user,p, replace, replacer, full)
    end
  end

  for i=-1,1,2 do
    local p = {x=pos.x, y=pos.y+i, z=pos.z}
    local n = minetest.env:get_node(p).name
  if n == replace then
      minetest.env:set_node(pos,{name=node})
      paint.replace(user,p, replace, replacer, full)
    end
  end
  for i=-1,1,2 do
    local p = {x=pos.x, y=pos.y, z=pos.z+i}
    local n = minetest.env:get_node(p).name
    if n == replace then
      minetest.env:set_node(pos,{name=node})
      paint.replace(user,p, replace, replacer, full)
    end
  end
end

--tools
minetest.register_tool("mtpaint:eraser", {
  description = "Eraser",
  inventory_image = "paint_eraser.png",
  on_use = function(itemstack, user, pointed_thing)
    if pointed_thing.type == "node" then
      minetest.env:remove_node(pointed_thing.under)
    end
  end,
})

minetest.register_tool("mtpaint:pencil", {
  description = "Pencil",
  inventory_image = "paint_pencil.png",
  on_use = function(itemstack, user, pointed_thing)
    if pointed_thing.type == "node" then
      local node = user:get_inventory():get_stack("main", 1):get_name()
      if user:get_player_control().sneak then
        minetest.env:set_node(pointed_thing.under,{name=node})
      else
        minetest.env:set_node(pointed_thing.above,{name=node})
      end
    end
    return
  end,
  on_place = function(self, user, pointed_thing)
    if pointed_thing.type == "node" then
      local node = user:get_inventory():get_stack("main", 2):get_name()
      if user:get_player_control().sneak then
        minetest.env:set_node(pointed_thing.under,{name=node})
      else
        minetest.env:set_node(pointed_thing.above,{name=node})
      end
    end
    return
  end,
})

minetest.register_tool("mtpaint:picker", {
  description = "Picker",
  inventory_image = "paint_picker.png",
  on_use = function(itemstack, user, pointed_thing)
    if pointed_thing.type == "node" then
      local node = minetest.env:get_node(pointed_thing.under).name
      if node == nil or node == "ignore" then return end
      local oldnode = user:get_inventory():get_stack("main", 1):get_name()
      local stack = ItemStack(oldnode)
      local inv = user:get_inventory()
      inv:set_stack("main", 1, node)
      if inv:contains_item("main", oldnode) then
      else
        if inv:room_for_item("main", stack) then
          inv:add_item("main", oldnode.." 1")
        end
      end
    end
    return
  end,
  on_place = function(self, user, pointed_thing)
    if pointed_thing.type == "node" then
      local node = minetest.env:get_node(pointed_thing.under).name
      if node == nil or node == "ignore" then return end
      local oldnode = user:get_inventory():get_stack("main", 2):get_name()
      local stack = ItemStack(oldnode)
      local inv = user:get_inventory()
      inv:set_stack("main", 2, node)
      if inv:contains_item("main", oldnode) then
      else
        if inv:room_for_item("main", stack) then
          inv:add_item("main", oldnode.." 1")
        end
      end
    end
    return
  end,
})

minetest.register_tool("mtpaint:fill", {
  description = "Fill",
  inventory_image = "paint_fill.png",
  on_use = function(itemstack, user, pointed_thing)
    if pointed_thing.type == "node" then
      local pos = pointed_thing.under
      local replace = minetest.env:get_node(pos).name
      local replacer = user:get_inventory():get_stack("main", 1):get_name()
      paint.loops = 0
      if user:get_player_control().sneak then
        paint.replace(user, pos, replace, replacer, true)
      else
        paint.replace(user, pos, replace, replacer, false)
      end
    end
    return
  end,
  on_place = function(itemstack, user, pointed_thing)
    if pointed_thing.type == "node" then
      local pos = pointed_thing.under
      local replace = minetest.env:get_node(pos).name
      local replacer = user:get_inventory():get_stack("main", 2):get_name()
      paint.loops = 0
      if user:get_player_control().sneak then
        paint.replace(user, pos, replace, replacer, true)
      else
        paint.replace(user, pos, replace, replacer, false)
      end
    end
    return
  end,
  
})

--[[WIP
minetest.register_tool("mtpaint:select_square", {
  description = "Square selection",
  inventory_image = "paint_select_square.png",
  on_use = function(itemstack, user, pointed_thing)
    if pointed_thing.under then
      minetest.env:remove_node(pointed_thing.under)
    end
  end,
})

minetest.register_tool("mtpaint:select_ellipse", {
  description = "Ellipse selection",
  inventory_image = "paint_select_ellipse.png",
  on_use = function(itemstack, user, pointed_thing)
    if pointed_thing.under then
      minetest.env:remove_node()
    end
  end,
})
]]--