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-- `Camera`
-- Used in drawing.
-- Metatable of `Camera`
Camera = {
x = 0,
y = 0,
dest_x = 0,
dest_y = 0,
scale = 4,
world = nil, -- game world
}
-- Constructor of `Camera`
function Camera:new (world)
local o = {}
setmetatable(o, self)
self.__index = self
o.world = world
return o
end
-- Drawing offsets
function Camera:getOffsets ()
return -self.x,-self.y
end
-- Position
function Camera:setPosition (x, y)
local x = x or 0
local y = y or 0
self.x, self.y = x, y
end
-- Destination
function Camera:setDestination (x, y)
local x = x or 0
local y = y or 0
self.dest_x, self.dest_y = x, y
end
function Camera:getDestination ()
return self.dest_x, self.dest_y
end
-- Move follow
function Camera:follow ()
local x,y,i = 145, 90, 1
for k,point in pairs(self.world.Nauts) do
if point.body:getX() > -20 and point.body:getX() < 310 and
point.body:getY() > -70 and point.body:getY() < 200 then
i = i + 1
x = point.body:getX() + x
y = point.body:getY() + y
end
end
x = x / i - 145
y = y / i - 90
self:setDestination(x,y)
end
-- Update
function Camera:update (dt)
self:follow()
local dx, dy = self:getDestination()
dx = (dx - self.x) * 6 * dt
dy = (dy - self.y) * 6 * dt
self:setPosition(self.x + dx, self.y + dy)
end
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