Factorio Forums

Code: Select all

character_is_moving = false
path_index = 1
path = nil

-- Determines which direction the character should go.
local function get_direction(start_position, end_position)
    local angle = math.atan2(end_position.y - start_position.y, start_position.x - end_position.x)

    -- Given a circle representing the angles, it is divided into eight octants representing the cardinal directions.
    local octant = (angle + math.pi) / (2 * math.pi) * 8 + 0.5

    if octant < 1 then
        return defines.direction.east
    elseif octant < 2 then
        return defines.direction.northeast
    elseif octant < 3 then
        return defines.direction.north
    elseif octant < 4 then
        return defines.direction.northwest
    elseif octant < 5 then
        return defines.direction.west
    elseif octant < 6 then
        return defines.direction.southwest
    elseif octant < 7 then
        return defines.direction.south
    else
        return defines.direction.southeast
    end
end

function positions_approximately_equal(a, b)
    return math.abs(a.x - b.x) < 0.25 and math.abs(a.y - b.y) < 0.25
end

-- Requests a path when the map is clicked.
script.on_event("mouse-click", function (event)
    local surface = game.get_surface("nauvis")
    local character = game.get_player(1).character
    surface.request_path{
        bounding_box = character.bounding_box,
        collision_mask = character.prototype.collision_mask,
        start = character.position,
        goal = event.cursor_position,
        force = "player"
    }
end)

-- Initializes the movement process when the path is received.
script.on_event(defines.events.on_script_path_request_finished, function (event)
    character_is_moving = true
    path = event.path
    path_index = 1
end)

-- Moves the character.
script.on_event(defines.events.on_tick, function (event)
    local character = game.get_player(1).character
    if character_is_moving and path ~= nil then
        if positions_approximately_equal(character.position, path[path_index].position) then
            -- waypoint reached
            path_index = path_index + 1  -- select the next waypoint
        end

        if path_index == #path then
            character_is_moving = false
            path_index = 1
        else
            -- move the character for one tick
            game.get_player(1).walking_state = {
                walking = true,
                direction = get_direction(character.position, path[path_index].position)
            }
        end
    end
end)