function board:animate_move_ace_to_well(card, well)
 local slot_layout=self.ruleset.layouts:slot(
  self.ruleset.n_slots\2+1
 )
 local well_layout=self.ruleset.layouts:well(well)

 local start_x,start_y=slot_layout:place_card(1)
 local end_x,end_y=well_layout:place_card(1)  -- index shouldn't matter

 local _self=self
 self:_animate_move_card(
  card,function() _self.wells[well]:add(card) end,
  start_x,start_y,function() return end_x,end_y end
 )
end

function board:animate_move_new_card_to_slot(card, slot)
 local src_layout=self.ruleset.layouts:slot(self.ruleset.n_slots\2+1)
 local dst_layout=self.ruleset.layouts:slot(slot)
 local start_x,start_y=src_layout:place_card(1)
 
 local _self=self
 self:_animate_move_card(
  card,function() _self.slots[slot]:add(card) end,
  start_x,start_y,function()
   return dst_layout:place_card(#_self.slots[slot].contents+1)
  end
 )
end

function board:animate_and_move_to_well(slot, well)
 local slot_layout=self.ruleset.layouts:slot(slot)
 local well_layout=self.ruleset.layouts:well(well)
 local start_x,start_y=slot_layout:place_card(#self.slots[slot].contents)
 local end_x,end_y=well_layout:place_card(1)  -- index shouldn't matter

 local card=self.slots[slot]:pop()

 local _self=self
 self:_animate_move_card(
  card,function() _self.wells[well]:add(card) end,
  start_x,start_y,function() return end_x,end_y end
 )
end

function board:_animate_move_card(card,on_end,start_x,start_y,compute_end)
 local frame=0
 local progress=0.0

 local anim_obj={}

 local end_x,end_y=start_x,start_y
 local _self=self
 function anim_obj:update()
  if (frame==0) end_x,end_y=compute_end()
  frame+=1
  progress=frame/7
  if (progress>=1.0) on_end() return false
  return true
 end
 function anim_obj:draw()
  local x=start_x+(end_x-start_x)*progress
  local y=start_y+(end_y-start_y)*progress
  _self.ruleset.deck:draw_card(x,y,card,false)
 end

 self.animator:add(anim_obj)
end