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diff --git a/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForcePullToGrid.lua b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForcePullToGrid.lua
new file mode 100644
index 0000000000..5f53f5da78
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+++ b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForcePullToGrid.lua
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+-- Copyright 2014 by Ida Bruhns
+--
+-- This file may be distributed and/or modified
+--
+-- 1. under the LaTeX Project Public License and/or
+-- 2. under the GNU Public License
+--
+-- See the file doc/generic/pgf/licenses/LICENSE for more information
+
+
+--- This is a subclass of ForceTemplate, which is used to implement forces
+-- that work on individual vertices and pulls them to a virtual grid with
+-- cells of the size determined by the user options |grid x length| and
+-- |grid y length|. The forces depend on the canvas position
+-- of the vertices relative to th next grid point. This class is e.\,g.\ used
+-- for the post-processing technique |snap to grid|.
+
+
+-- Imports
+local ForceTemplate = require "pgf.gd.force.jedi.base.ForceTemplate"
+local lib = require "pgf.gd.lib"
+local Preprocessing = require "pgf.gd.force.jedi.base.Preprocessing"
+
+-- Localize math functions
+local max = math.max
+local sqrt = math.sqrt
+local min = math.min
+local floor = math.floor
+local round
+function round(number)
+ return floor((number * 10 + 0.5) / 10)
+end
+
+-- Implementation starts here:
+
+local ForcePullToGrid = lib.class { base_class = ForceTemplate }
+
+function ForcePullToGrid:constructor ()
+ ForceTemplate.constructor(self)
+ self.p = {}
+end
+
+-- This force class works on individual vertices and only depends on their
+-- current position. Thus the vertex table of the current graph is simply
+-- copied to the variable |p|.
+--
+-- @param v The vertices of the graph we are trying to find a layout for.
+
+function ForcePullToGrid:preprocess(v)
+ self.p = v
+end
+
+
+-- Applying the force to the vertices and adding the effect to the passed net
+-- force array
+--
+-- @param data The parameters needed to apply the force: The options table,
+-- the current time stamp, an array containing the summed up net
+-- forces
+
+function ForcePullToGrid:applyTo(data)
+ -- locals for speed
+ local cap = self.force.cap
+ local net_forces = data.net_forces
+ local t_max = self.options["maximum time"]
+ local grid_x_distance = self.options["grid x length"]
+ local grid_y_distance = self.options["grid y length"]
+ local t_now = data.t_now
+ local p = self.p
+ local time_fun = self.force.time_fun
+ local length = 5--self.options["node distance"]
+
+ -- Evaluate time function
+ local time_factor = time_fun(t_max, t_now)
+ if time_factor == 0 then
+ return
+ end
+
+ for _, v in ipairs(p) do
+ -- dereference
+ local p1 = v.pos
+ local p2_x = round(p1.x/grid_x_distance)*grid_x_distance
+ local p2_y = round(p1.y/grid_y_distance)*grid_y_distance
+
+ -- calculate distance between vertex and grid point
+ local x = p1.x - p2_x
+ local y = p1.y - p2_y
+ local d = max(sqrt(x*x+y*y),0.1)
+ local l = -d/(length*length)
+
+ -- Include time function
+ local h = l * time_factor
+
+ -- scale effect according to direction
+ local f = x * h
+ local g = y * h
+
+ -- cap effect if necessary
+ if cap then
+ if f <= 0 then
+ x = max(-cap, f)
+ else
+ x = min(cap, f)
+ end
+
+ if g <= 0 then
+ y = max(-cap, g)
+ else
+ y = min(cap, g)
+ end
+ else
+ x = f
+ y = g
+ end
+
+ -- add calculated effect to net forces
+ local c1 = net_forces[v]
+ c1.x = c1.x - x
+ c1.y = c1.y - y
+ end
+end
+
+return ForcePullToGrid \ No newline at end of file