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-rw-r--r--graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceAbsoluteValue.lua94
-rw-r--r--graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceCanvasDistance.lua201
-rw-r--r--graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceCanvasPosition.lua117
-rw-r--r--graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceGraphDistance.lua205
-rw-r--r--graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForcePullToGrid.lua123
-rw-r--r--graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForcePullToPoint.lua119
6 files changed, 859 insertions, 0 deletions
diff --git a/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceAbsoluteValue.lua b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceAbsoluteValue.lua
new file mode 100644
index 0000000000..4634b70123
--- /dev/null
+++ b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceAbsoluteValue.lua
@@ -0,0 +1,94 @@
+-- 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. Forces of this kind simply add an
+-- absolute value set in the force data to each vertex' $x$ and $y$ coordinate
+
+-- 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
+
+-- Implementation starts here:
+
+local ForceAbsoluteValue = lib.class { base_class = ForceTemplate }
+
+function ForceAbsoluteValue:constructor ()
+ ForceTemplate.constructor(self)
+ self.p = {}
+end
+
+
+-- This force class works on a vertex array that is part of the force data
+-- defined when adding the force. This array is copied into p. All vertices of
+-- the graph are saved in the local variable |ver|.
+--
+-- @param v The vertices of the graph we are trying to find a layout for.
+
+function ForceAbsoluteValue:preprocess(v)
+ self.ver = v
+ self.p = self.force.vertices
+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 ForceAbsoluteValue:applyTo(data)
+ -- locals for speed
+ local cap = self.force.cap
+ local value = self.force.value
+ local net_forces = data.net_forces
+ local t_max = self.options["maximum time"]
+ local t_now = data.t_now
+ local p = self.p
+ local time_fun = self.force.time_fun
+
+ -- Evaluate time function
+ local time_factor = time_fun(t_max, t_now)
+ if time_factor == 0 then
+ return
+ end
+
+ for _,v in ipairs(self.ver) do
+ for _, i in ipairs (self.p) do
+ -- Is the vertex in the list?
+ if v.name == i then
+
+ local f = value * time_factor
+
+ -- cap effect if necessary
+ if cap then
+ if f <= 0 then
+ x = max(-cap, f)
+ else
+ x = min(cap, f)
+ end
+ end
+
+ -- add calculated effect to net forces
+ local c1 = net_forces[v]
+ c1.x = c1.x + f
+ c1.y = c1.y + f
+ end
+ end
+ end
+end
+
+return ForceAbsoluteValue \ No newline at end of file
diff --git a/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceCanvasDistance.lua b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceCanvasDistance.lua
new file mode 100644
index 0000000000..8cea1aec6a
--- /dev/null
+++ b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceCanvasDistance.lua
@@ -0,0 +1,201 @@
+-- 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 between
+-- vertex pairs. The forces depend on the canvas distance of the vertices in
+-- the pair. This class is e.~g.~ used for electric forces.
+
+-- 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
+
+-- Implementation starts here:
+local ForceCanvasDistance = lib.class { base_class = ForceTemplate }
+
+function ForceCanvasDistance:constructor ()
+ ForceTemplate.constructor(self)
+ self.p = {}
+end
+
+
+-- This force class works on all pairwise disjoint vertex pairs. This
+-- function generates a new graph object containing all vertices from the
+-- original graph and arcs between all pairwise disjoint vertex pairs. The
+-- arcs-table of this new object will be saved in the variable |p|.
+--
+-- @param v The vertices of the graph we are trying to find a layout for.
+
+function ForceCanvasDistance:preprocess(v)
+ self.p = Preprocessing.allPairs(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 ForceCanvasDistance:applyTo(data)
+ -- locals for speed
+ local cap = self.force.cap
+ local fun_u = self.force.fun_u
+ local fun_v = self.force.fun_v
+ local net_forces = data.net_forces
+ local t_max = self.options["maximum time"]
+ local t_now = data.t_now
+ local k = data.k
+ local p = self.p
+ local time_fun = self.force.time_fun
+ local fw_attributes = self.fw_attributes
+
+ -- Evaluate time function
+ local time_factor = time_fun(t_max, t_now)
+ if time_factor == 0 then
+ return
+ end
+
+ if not fun_v then
+ local data = { k = k, attributes = fw_attributes }
+ for _, i in ipairs(p) do
+ -- dereference
+ local p2 = i.head
+ local p1 = i.tail
+ local p2_pos = p2.pos
+ local p1_pos = p1.pos
+
+ -- calculate distance between two points
+ local x = p2_pos.x - p1_pos.x
+ local y = p2_pos.y - p1_pos.y
+ local d = max(sqrt(x*x+y*y),0.1)
+
+ -- apply force function
+ data.u = p2
+ data.v = p1
+ data.d = d
+ local e = fun_u(data)
+
+ -- Include time function
+ local f = e * time_factor / d
+
+ -- calculate effect on x/y
+ local g = x * f
+ local h = y * f
+
+ -- cap effect if necessary
+ if cap then
+ if g <= 0 then
+ x = max(-cap, g)
+ else
+ x = min(cap, g)
+ end
+
+ if h <= 0 then
+ y = max(-cap, h)
+ else
+ y = min(cap, h)
+ end
+ else
+ x = g
+ y = h
+ end
+
+ -- add calculated effect to net forces
+ local c1 = net_forces[p1]
+ c1.x = c1.x - x
+ c1.y = c1.y - y
+ local c2 = net_forces[p2]
+ c2.x = c2.x + x
+ c2.y = c2.y + y
+ end
+ else
+ -- There are different functions for head and tail vertex
+ local data = { k = k, attributes = fw_attributes }
+ for _, i in ipairs(p) do
+ -- dereference
+ local p2 = i.head
+ local p1 = i.tail
+ local p2_pos = p2.pos
+ local p1_pos = p1.pos
+
+ -- calculate distance between two points
+ local x = p2_pos.x - p1_pos.x
+ local y = p2_pos.y - p1_pos.y
+ local d = max(sqrt(x*x+y*y),0.1)
+
+ -- apply force function to distance and k (natural spring length
+ data.u = p2
+ data.v = p1
+ data.d = d
+ local e_head = fun_u(data)
+ local e_tail = fun_v(data)
+
+ -- Include time function
+ local f_head = time_factor * e_head / d
+ local f_tail = time_factor * e_tail / d
+
+ -- calculate effect on x/y
+ local g_head = x * f_head
+ local g_tail = x * f_tail
+ local h_head = y * f_head
+ local h_tail = y * f_tail
+
+ -- cap effect if necessary
+ local x_head, x_tail, y_head, y_tail
+ if cap then
+ if g_head <= 0 then
+ x_head = max(-cap, g_head)
+ else
+ x_head = min(cap, g_head)
+ end
+
+ if g_tail <= 0 then
+ x_tail = max(-cap, g_tail)
+ else
+ x_tail = min(cap, g_tail)
+ end
+
+ if h_head <= 0 then
+ y_head = max(-cap, h_head)
+ else
+ y_head = min(cap, h_head)
+ end
+
+ if h_tail <= 0 then
+ y_tail = max(-cap, h_tail)
+ else
+ y_tail = min(cap, h_tail)
+ end
+ else
+ x_head = g_head
+ x_tail = g_tail
+ y_head = h_head
+ y_tail = h_tail
+ end
+
+ -- add calculated effect to net forces
+ local c1 = net_forces[p1]
+ c1.x = c1.x - x_tail
+ c1.y = c1.y - y_tail
+ local c2 = net_forces[p2]
+ c2.x = c2.x + x_head
+ c2.y = c2.y + y_head
+ end
+ end
+end
+
+return ForceCanvasDistance \ No newline at end of file
diff --git a/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceCanvasPosition.lua b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceCanvasPosition.lua
new file mode 100644
index 0000000000..41edaba358
--- /dev/null
+++ b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceCanvasPosition.lua
@@ -0,0 +1,117 @@
+-- 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. The forces depend on the canvas position
+-- of the vertices. This class is e.~g.~ used for gravitational forces.
+
+local ForceTemplate = require "pgf.gd.force.jedi.base.ForceTemplate"
+local lib = require "pgf.gd.lib"
+
+local ForceCanvasPosition = lib.class { base_class = ForceTemplate }
+
+-- Localize math functions
+local max = math.max
+local sqrt = math.sqrt
+local min = math.min
+
+-- Implementation starts here:
+
+function ForceCanvasPosition: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 ForceCanvasPosition: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 ForceCanvasPosition:applyTo(data)
+ --localize
+ local cap = self.force.cap
+ local fun_u = self.force.fun_u
+ local net_forces = data.net_forces
+ local t_max = self.options["maximum time"]
+ local t_now = data.t_now
+ local p = self.p
+ local time_fun = self.force.time_fun
+ local initial_gravity = self.options["gravity"]
+ local fw_attributes = self.fw_attributes
+
+ -- evaluate time function
+ local time_factor = time_fun(t_max, t_now)
+ if time_factor == 0 then
+ return
+ end
+
+ -- Find midpoint of all vertices since they will be attracted to this point
+ local centroid_x, centroid_y = 0,0
+ for _, v in ipairs(p) do
+ local pos = v.pos
+ centroid_x = centroid_x + pos.x
+ centroid_y = centroid_y + pos.y
+ end
+ centroid_x = centroid_x/#p
+ centroid_y = centroid_y/#p
+
+ -- Iterate over the precomputed vertex list
+ for _, v in ipairs(p) do
+ -- localize
+ local p1 = v.pos
+
+ -- apply force function
+ local factor = fun_u{attributes = fw_attributes, u = v}
+
+ -- calculate distance between vertex and centroid
+ local x = centroid_x - p1.x
+ local y = centroid_y - p1.y
+
+ -- calculate effect on x/y
+ local h = factor * time_factor
+ x = x * h
+ y = y * h
+
+ -- cap effect if necessary
+ if cap then
+ if x <= 0 then
+ x = max(-cap, x)
+ else
+ x = min(cap, x)
+ end
+ if y <= 0 then
+ y = max(-cap, y)
+ else
+ y = min(cap, y)
+ end
+ end
+
+ -- add calculated effect to net forces
+ local c = net_forces[v]
+ c.x = c.x + x
+ c.y = c.y + y
+ end
+end
+
+return ForceCanvasPosition \ No newline at end of file
diff --git a/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceGraphDistance.lua b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceGraphDistance.lua
new file mode 100644
index 0000000000..86d67f2678
--- /dev/null
+++ b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForceGraphDistance.lua
@@ -0,0 +1,205 @@
+-- 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 between
+-- vertex pairs. The forces depend on the graph distance of the vertices in
+-- the pair. This class is e.\,g.\ used for spring forces.
+
+
+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
+
+-- Implementation starts here:
+
+local ForceGraphDistance = lib.class { base_class = ForceTemplate }
+
+function ForceGraphDistance:constructor ()
+ ForceTemplate.constructor(self)
+ self.p = {}
+end
+
+
+-- This force class works on all pairwise disjoint vertex pairs connected by
+-- a path of length maximum $n$. The parameter $n$ is given by the engineer in
+-- the force declaration. This function generates a new graph object
+-- containing all vertices from the original graph and arcs between all
+-- pairwise disjoint vertex pairs. The arcs-table of this new object will be
+-- saved in the variable |p|.
+--
+-- @param v The vertices of the graph we are trying to find a layout for.
+
+function ForceGraphDistance:preprocess(v, a)
+ self.p = Preprocessing.overExactlyNPairs(v, a, self.force.n)
+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 ForceGraphDistance:applyTo(data)
+ -- locals for speed
+ local cap = self.force.cap
+ local fun_u = self.force.fun_u
+ local fun_v = self.force.fun_v
+ local net_forces = data.net_forces
+ local t_max = self.options["maximum time"]
+ local t_now = data.t_now
+ local k = data.k
+ local p = self.p
+ local time_fun = self.force.time_fun
+ local fw_attributes = self.fw_attributes
+
+ -- Evaluate time function
+ local time_factor = time_fun(t_max, t_now)
+ if time_factor == 0 then
+ return
+ end
+
+ if not fun_v then
+ local data = { k = k, attributes = fw_attributes }
+ for _, i in ipairs(p) do
+ -- dereference
+ local p2 = i.head
+ local p1 = i.tail
+ local p2_pos = p2.pos
+ local p1_pos = p1.pos
+
+ -- calculate distance between two points
+ local x = p2_pos.x - p1_pos.x
+ local y = p2_pos.y - p1_pos.y
+ local d = max(sqrt(x*x+y*y),0.1)
+
+ -- apply force function to distance and k (natural spring length)
+ data.u = p2
+ data.v = p1
+ data.d = d
+ local e = fun_u(data)
+
+ -- Include time function
+ local f = e * time_factor / d
+
+ -- calculate effect on x/y
+ local g = x * f
+ local h = y * f
+
+ -- cap effect if necessary
+ if cap then
+ if g <= 0 then
+ x = max(-cap, g)
+ else
+ x = min(cap, g)
+ end
+
+ if g <= 0 then
+ y = max(-cap, h)
+ else
+ y = min(cap, h)
+ end
+ else
+ x = g
+ y = h
+ end
+
+ -- add calculated effect to net forces
+ local c1 = net_forces[p1]
+ c1.x = c1.x - x
+ c1.y = c1.y - y
+ local c2 = net_forces[p2]
+ c2.x = c2.x + x
+ c2.y = c2.y + y
+ end
+ else
+ -- There are different functions for head and tail vertex
+ local data = { k = k, attributes = fw_attributes }
+ for _, i in ipairs(p) do
+ -- dereference
+ local p2 = i.head
+ local p1 = i.tail
+ local p2_pos = p2.pos
+ local p1_pos = p1.pos
+
+ -- calculate distance between two points
+ local x = p2_pos.x - p1_pos.x
+ local y = p2_pos.y - p1_pos.y
+
+ local d = max(sqrt(x*x+y*y),0.1)
+
+ -- apply force function to distance and k (natural spring length
+ data.u = p2
+ data.v = p1
+ data.d = d
+ local e_head = fun_u(data)
+ local e_tail = fun_v(data)
+
+ -- Include time function
+ local f_head = time_factor * e_head / d
+ local f_tail = time_factor * e_tail / d
+
+ -- calculate effect on x/y
+ local g_head = x * f_head
+ local g_tail = x * f_tail
+ local h_head = y * f_head
+ local h_tail = y * f_tail
+
+ -- cap effect if necessary
+ local x_head, x_tail, y_head, y_tail
+ if cap then
+ if g_head <= 0 then
+ x_head = max(-cap, g_head)
+ else
+ x_head = min(cap, g_head)
+ end
+
+ if g_tail <= 0 then
+ x_tail = max(-cap, g_tail)
+ else
+ x_tail = min(cap, g_tail)
+ end
+
+ if h_head <= 0 then
+ y_head = max(-cap, h_head)
+ else
+ y_head = min(cap, h_head)
+ end
+
+ if h_tail <= 0 then
+ y_tail = max(-cap, h_tail)
+ else
+ y_tail = min(cap, h_tail)
+ end
+ else
+ x_head = g_head
+ x_tail = g_tail
+ y_head = h_head
+ y_tail = h_tail
+ end
+
+ -- add calculated effect to net forces
+ local c1 = net_forces[p1]
+ c1.x = c1.x - x_tail
+ c1.y = c1.y - y_tail
+ local c2 = net_forces[p2]
+ c2.x = c2.x + x_head
+ c2.y = c2.y + y_head
+ end
+ end
+end
+
+return ForceGraphDistance \ No newline at end of file
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
--- /dev/null
+++ b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForcePullToGrid.lua
@@ -0,0 +1,123 @@
+-- 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
diff --git a/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForcePullToPoint.lua b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForcePullToPoint.lua
new file mode 100644
index 0000000000..985b8eec2e
--- /dev/null
+++ b/graphics/pgf/base/tex/generic/graphdrawing/lua/pgf/gd/force/jedi/forcetypes/ForcePullToPoint.lua
@@ -0,0 +1,119 @@
+-- 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 specific point on the
+-- canvas. This point is given by the |desired at| option. The forces depend
+-- on the canvas position of the vertices relative to the canvas point it is
+-- pulled to.
+
+
+-- 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
+
+-- Implementation starts here:
+
+local ForcePullToPoint = lib.class { base_class = ForceTemplate }
+
+function ForcePullToPoint:constructor ()
+ ForceTemplate.constructor(self)
+ self.p = {}
+end
+
+-- This force class works on individual vertices and depends on their
+-- current position as well as the point it is desired at. Thus all vertices
+-- where the |desired at| option is set are added to the table |p| together
+-- with the point where they are wanted.
+--
+-- @param v The vertices of the graph we are trying to find a layout for.
+
+function ForcePullToPoint:preprocess(v)
+ for _,vertex in ipairs(v) do
+ if vertex.options then
+ local da = vertex.options["desired at"]
+ if da then
+ self.p[vertex]= {da}
+ end
+ end
+ end
+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 ForcePullToPoint:applyTo(data)
+ -- locals for speed
+ local cap = self.force.cap
+ local net_forces = data.net_forces
+ local t_max = self.options["maximum time"]
+ local t_now = data.t_now
+ local p = self.p
+ local time_fun = self.force.time_fun
+
+ -- Evaluate time function
+ local time_factor = time_fun(t_max, t_now)
+ if time_factor == 0 then
+ return
+ end
+
+ for v, point in pairs(p) do
+ -- dereference
+ local p1 = v.pos
+ local p2 = point[1]
+
+ -- calculate distance between vertex and centroid
+ local x = p1.x - p2.x
+ local y = p1.y - p2.y
+ local d = max(sqrt(x*x+y*y),0.1)
+
+ -- Include time function
+ local h = d * 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 ForcePullToPoint \ No newline at end of file