Windows
There are five main types of window in TreeMaker (as well as assorted
dialog boxes). They are:
-
The Design window, in which you construct your
design and TreeMaker constructs the crease pattern. There is one
of these windows for each document.
-
The Inspector window, which displays attributes of
your design and the various objects that make up a TreeMaker
pattern. The Inspector shows information about the active (usually
frontmost) document.
-
The Folded Form window, which displays a
silhouette of the folded base after it is designed. The Folded Form window
shows information about the active document.
-
The View Settings window, which lets you
change how TreeMaker displays and prints the design and crease
pattern. The View Settings window shows the settings for the active
document.
-
The Help window, which displays this documentation,
which can also be printed out.
The following sections describe these windows.
-
Note: all of the screen images are taken from the Macintosh version of
TreeMaker. Windows on other platforms should look similar in
their content, but may have differences in title bars, borders, and/or
size controls.
Each origami design is its own document and is displayed within a single
window. An origami design is composed of a number of interrelated "parts". The
different types of parts are called:
-
node --- represents the endpoint of a flap or a junction between flaps in
the desired base.
-
edge --- represents a flap in the desired base.
-
path --- represents a distance relationship between any two nodes. The
vertices corresponding to any two leaf nodes must have a separation on the
paper greater than or equal to their separation on the tree; a path
captures this requirement.
-
poly --- a polygon, whose corners are nodes and whose edges are (certain)
paths. Polygons get filled with the crease patterns known as
molecules.
-
vertex --- a point in the crease pattern where two or more creases come
together.
-
crease --- a fold line within the crease pattern. Creases can be folded or
unfolded; folded creases can be mountain or valley.
-
facet --- a polygonal region within the crease pattern. The corners of
facets are vertices; the sides of facets are creases.
-
condition --- represents a user-specified relationship among nodes, edges,
and/or paths to impose symmetry or other requirements on the crease pattern
and/or the tree.
Each type of part has a graphical representation in the Design window that can
be turned on or off and otherwise altered in various ways through the View Settings window. Each type of part has a
characteristic color scheme as well. The color scheme and possibilities for
graphical display of each type of part are described below in the View Settings window section.
Figures W-1 to W-4 show four views of a typical window that display all of the
different parts. These images are taken from the Mac version of
TreeMaker, but other platforms should look similar.
Figure W-1 shows a design window after a tree has been defined in Design View.
The visible objects include the nodes and edges of the tree; the paths that
form the convex hull of the leaf nodes of the tree; and circles around each
leaf node that indicate the minimum amount of paper needed to fold the flaps
corresponding to the edges incident on each leaf node. (These are the circles
used in "circle packing" origami design.)

Figure W-1.
Figure W-2 shows a design window after the tree has been optimized, also in
Design View. Optimization finds the positions of the nodes (and their
corresponding crease pattern vertices) that maximizes the size of the resulting
base.

Figure W-2.
Figure W-3 shows a design window after the crease pattern has been constructed,
again in Design View. Visible are nodes, edges, paths, vertices, and creases,
the latter drawn in "AGRH" style. The crease pattern is constructed from the
node positions found in optimization.

Figure W-3.
Figure W-4 shows the same design window after the crease pattern has been
constructed, now in Plan View. Visible are vertices and creases, with mountain,
valley, and unfolded creases identified, and coordinates given for the vertices.

Figure W-4.
These are many different ways of viewing the same design. As is shown in the
next section, you can use the View->Show View Settings/Hide View
Settings command to select which parts are shown and how they are shown.
The bottom of the Design window shows the scale of the current design. The
scale is the relationship between one edge unit and the size of the paper, and
is a measure of how large the folded shape will be relative to the size of the
paper. The rest of the window shows all the parts.
The collection of nodes and edges, which specifies the structure of the desired
base, is known as a tree. Lines between pairs of nodes on the paper
are paths. There is a path between most pairs of nodes, but most paths
are not shown most of the time (or in the windows above). Groups of certain
paths form larger-scale structures called polys ("poly" is short for
"polygon" and I'll use the two terms more or less interchangeably). Each poly
contains a portion of the overall crease pattern. The crease pattern is made up
of vertices, creases, and facets. The design of an
origami base is accomplished in three steps:
-
Construction of a tree and specification of the desired attributes of the
base. This is done by you using various editing tools.
-
Placement of the nodes in a valid configuration. This is computed by
TreeMaker, using a process of optimization, which you can control
by various settings and conditions. The node positions form the "skeleton"
of the crease pattern.
-
Construction of the polys, vertices, and creases, forming the crease
pattern for the base. This is also computed by TreeMaker.
What parts are shown and how they are shown in the main window can be altered
with the View->Show View Settings/Hide View Settings menu command. There
are four predefined combinations of view settings that may be set from the
View menu:
-
Tree View --- this view shows only the tree: nodes, edges, and conditions
upon them.
-
Design View --- this is the standard view, which is typically used when
constructing the tree. It shows the tree and conditions, and if a crease
pattern is present, overlays the crease pattern on top of the tree.
-
Creases View --- this shows just the crease pattern with creases shown as
mountain or valley folds.
-
Plan View --- this is the same as Creases View, but with the addition
that coordinates of some of the vertices are shown. This is particularly
useful for transferring a crease pattern to another sheet of paper by
measuring and marking and/or for constructing folding sequences using a
tool like ReferenceFinder.
Other combinations of settings are posible by going to the View Settings window, see below.
When the document is printed, the first page of the printout will contain
whatever is in the main design window: the tree, a partially-optimized tree, or
the completed crease pattern.
Creating a new Tree
When a window is first opened, it will be in Default View showing a blank
square, as shown in Figure W-5.

Figure W-5. Initial window for a newly-created document shows a blank
square.
You define the tree by pointing and clicking in the square to draw a stick
figure that defines the topology of the desired origami base. Clicking once in
the square produces a node at the location of the click, as shown in Figure
W-6. Leaf nodes (nodes with 0 or 1 incident edge) are shown by default
surrounded by a circle. When a node is selected it (and its surrounding circle)
is highlighted, that is, shown with a slightly larger dot/thicker line/darker
fill than in the unhighlighted case.

Figure W-6. Clicking once in the blank square creates a new node.
If a single node is highlighted, clicking in another location will add a node
with an edge connecting the two, as shown in Figure W-7.

Figure W-7. When a node is highlighted, clicking somewhere else will
add an edge from the highlighted node to the location of the click.
When an edge is first created, it will have a default length of 1 unit. As
already noted, a node with only one edge attached is called a leaf
node. A node with two or more edges attached is called a branch
node.
In this example, node 2 is selected, so clicking in a new location will create
another new node and edge as shown in Figure W-8.

Figure W-8. Clicking again creates a new leaf node and turns node 2
into a branch node.
You can add branches to the tree --- a branch is an edge that emanates from a
branch node --- by selecting the branch node and then clicking elsewhere in the
square, as shown in Figure W-9.

Figure W-9. A tree with three leaf nodes and one branch node.
You can select any visible part in the design window by clicking on the part.
You can select more than one part at a time and more than one type of part.
By holding down the shift and/or modifier keys as you click, you can change
the selection:
-
Clicking on a part (with no modifiers) makes it the current selection;
-
Clicking on an unselected part while holding the shift key down adds it to
the current selection;
-
Clicking on a selected part while holding the shift key down removes it from
the current selection;
An exception to the above comes when you add a node by clicking: if you hold
down the modifier key (Option on Mac, Alt on Windows, Alt or Control on Linux)
while clicking to add a node, the currently selected node is left unchanged.
In this way you can repeatedly add new nodes and edges to the same selected
node.
Between every two tree nodes is a line called a path. Most of the
time, paths are invisible. However, once a third node has been created, the
paths that form the convex hull of the nodes (called border paths)
will be visibly outlined as shown in Figure W-9.
Each edge of the tree corresponds to a flap of the base. The connections
between edges specify the way the flaps are connected. By repeatedly selecting
nodes and clicking, you can build up arbitrarily complex trees with any number
and arrangement of edges, which will specify a tree of the same complexity.
To remove a node or edge, simply select it by clicking on it and do one of the
following:
-
Select the Edit->Cut command
-
Select the Edit->Clear command
-
Hit the backspace, delete or forward delete key
For information about how to edit attributes of nodes and edges, read on.
Editing can happen in three ways:
-
Selecting commands from the menu (or their keyboard equivalents);
-
Clicking and dragging nodes and/or edges in the Design window;
-
Editing the attributes of parts in the Inspector window.
This last is the topic of the next section.
The Inspector window is a floating window that displays attributes of
the currently-selected part, or if no part is selected, attributes of the tree.
If multiple parts are selected, the Inspector shows how many of each
type of part there are in the selection. All parts (nodes, edges, paths, polys,
vertices, and creases) have attributes associated with them. Some are numerical
settings; some describe relationships to other parts. The Inspector
window is toggled on and off with the View->Show Inspector/Hide
Inspector command.
There is only one Inspector; it always displays information for the
active design window. The Inspector displays attributes of the tree or
a part of the tree. Some of the part attributes are user-editable; others are
computed by TreeMaker.
The Inspector displays different panels depending on what object or
objects are selected in the Design View window. The panels are:
The fields of the various inspector panels are described in the following
sections.

Figure W-10. The Tree panel displays settings that affect the entire
tree.
The Tree panel is shown when nothing is selected. The settings are:
-
Paper Width --- the desired width of the paper in dimensionless units. This
is typically 1.0.
-
Paper Height --- the desired height of the paper in dimensionless units.
This is typically 1.0. For rectangular paper, you can change either the
width or the height.
-
Scale --- the length of a tree unit on the square. That is, a 1-unit edge
will have this length relative to the paper. You can edit this value, but
it is usually found by TreeMaker as part of an optimization.
-
Symmetry --- Turns on mirror symmetry for the paper. There are two
predefined symmetry settings: "diag" symmetry makes a design symmetrical
along the diagonal of the square, while "book" symmetry creates a symmetry
line that runs vertically. You can also choose other symmetry lines by
editing the next three parameters, which set the symmetry angle and
identify a single point on the line of symmetry. Note that turning on this
setting this merely defines a line of symmetry; you must still create
conditions to force nodes or pairs of nodes to obey symmetric relationships.
-
X --- Set the x-coordinate of a point on the line of
symmetry.
-
Y --- Set the y-coordinate of a point on the line of
symmetry.
-
Angle --- Set the angle of the line of symmetry (in degrees
counterclockwise from the x-axis).
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
-
Conditions --- This listbox displays all conditions that have been set on
nodes, edges, paths, or combinations thereof. A condition can be edited by
double-clicking on its entry in this list.

Figure W-11. The Node panel displays attributes of a selected node.
A node is identified by its index. The attributes shown in the Node panel are:
-
Node Index --- Every part has an index; indices are numbered consecutively
from 1. Parts can be referenced by their index. The node with index 1 has a
special role: it is the root node, which defines the orientation
of the flaps in the folded base. (The root node corresponds to the tip of
the uppermost flap in the folded form.) If you change the index of a node
in this panel, other nodes will be renumbered accordingly.
-
X --- The x coordinate of the node. If this node is a leaf node,
its coordinates will be used for the coordinates of its corresponding
vertex. In other words, the tip of the flap that corresponds to the tree
edge incident to a leaf node comes from the point on the paper where that
node is located. Only leaf nodes' position is significant; the location of
a branch node has no effect, and you can move branch nodes around for best
visibility. TreeMaker optimization will usually find the positions
of the leaf nodes, but you can also set any node's position using this
panel or by clicking and dragging.
-
Y --- The y coordinate of the node.
-
Label --- This is an optional text label that you can put on a node to
indicate what part of the subject it represents, e.g., "head," "tail,"
"left leg," etc.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
-
Conditions --- This listbox displays all conditions that have been set on
this node. A condition can be edited by double-clicking on its entry in
this list.

Figure W-12. The Edge panel displays attributes of a selected edge.
An edge is identified by its index. The attributes shown in the Edge panel are:
-
Edge Index --- the index of the edge. The value has no effect; it is only
for reference.
-
Length --- the desired length of the associated flap, in tree units. The
actual length of the flap relative to the paper will be the product of the
strained length (see below) with the tree scale.
-
Strain --- a deviation from the desired length. Zero strain makes the edge
(and its associated flap) length equal to the value set in the length box.
If the strain is greater than 1, the flap will be longer; if less than 1,
it will be shorter. Some forms of optimization vary the strain in order to
satisfy additional conditions you may put on the tree.
-
Stiffness --- a measure of the resistance of an edge to strain. Larger
values of stiffness will force the strain to be small relative to other
edges with lower stiffness.
-
Label --- This is an optional text label that you can put on an edge to
indicate what part of the subject it represents, e.g., "head," "tail,"
"left leg," etc.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
-
Conditions --- This listbox displays all conditions that have been set on
this edge. A condition can be edited by double-clicking on its entry in
this list.

Figure W-13. The Path panel displays attributes of a selected path.
A path is identified by its index and by the two nodes that the path
connects. The attributes shown in the Path panel are:
-
Min Tree Length --- the minimum length of this path as measured on the tree.
This is the sum of the strained lengths of all edges in the path.
-
Act Tree Length --- the actual length of this path as measured on the paper,
scaled to the tree. If the actual length is greater than or equal to the
minimum length, the path is said to be feasible. If the two
lengths are equal, the path is said to be active.
-
Path Angle --- the angle that this path makes relative to the x axis.
-
Conditions --- This listbox displays all conditions that have been set on
this path. A condition can be edited by double-clicking on its entry in
this list.
None of the attributes of a path are editable; they are all set by
TreeMaker.

Figure W-14.The Poly panel displays attributes of a selected poly.
A poly is identified by its index. The attributes shown in the Poly panel are:
-
Centroid --- the coordinates of the "center of mass" of this poly. This is
also where its dot is shown when that is enabled in the View Settings window.
-
Ring Nodes --- the indices of the leaf nodes that are the corners of this
poly, given in counterclockwise order.
-
Ring Paths --- the indices of the paths that form the boundary of this
poly, given in counterclockwise order.
None of the attributes of a poly are editable; they are all set by
TreeMaker.
The Condition panel displays attributes of a selected condition. There are
several different condition panels, one for each type of condition. They are:
A condition is identified by its index. All condition panels display the index
of the condition and whether or not the condition is currently feasible. The
panels for the individual types of conditions display additional information
specific to the type of condition, described below.

Figure W-15. The Condition Node Fixed Panel displays attributes
of a Node Fixed condition.
The Node Fixed condition lets you constrain the position of a node in one
of several different ways. The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
Node --- the index of the node that this condition applies to. It will only
have an effect if the node is a leaf node.
-
fFixed to Symmetry Line --- check this box to constrain the node to lie on
the line of symmetry. It will only have an effect if you have checked the
"symmetry" checkbox in the tree inspector. Note that this condition puts
the node on the line of symmetry; to make the node symmetrically
paired with another node, use the Nodes Paired condition, see below.
-
Fixed to Paper Edge --- check this box to constrain the node to lie on any
of the four edges of the paper. The condition is satisfied no matter which
edge the node lies on. To constrain it to a particular edge, use the X or Y
coordinate fixed checkboxes.
-
Fixed to Paper Corner --- check this box to constrain the node to lie on any
of the four corners of the paper.
-
X Fixed to --- check this box to constrain the x coordinate
of the node. The box contains the value it is fixed to, which should lie
within the paper.
-
Y Fixed to --- check this box to constrain the y coordinate
of the node. The box contains the value it is fixed to, which should lie
within the paper.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
The Node Fixed condition replaces the next 4 conditions in this list, which
have been deprecated. TreeMaker will read version 4 files that contain
the old conditions, but you can only create Node Fixed conditions, which
combine the functionality of the version 4 conditions.
Note that it is quite possible to create inconsistent conditions: for example,
checking "fixed to paper corner" and "x coordinate fixed" with a value of 0.5.
If you set inconsistent conditions, TreeMaker will not find a solution.
It is up to you to avoid creating combinations of conditions that
are impossible to satisfy.

Figure W-16. The Condition Node Symmetric Panel displays attributes of
a Node Symmetric condition.
The Node Symmetric condition lets you constrain the position of a node to lie
on the line of symmetry. The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
Node --- the index of the node that this condition applies to. It will only
have an effect if the node is a leaf node.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
This condition has been deprecated; you should use the Node Fixed
condition in new designs.

Figure W-17. The Condition Node On Edge Panel displays attributes of a
Node on Edge condition.
The Node on Edge condition lets you constrain the position of a node to lie on
the edge of the paper (any edge will do). The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
Node --- the index of the node that this condition applies to. It will only
have an effect if the node is a leaf node.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
This condition has been deprecated; you should use the Node Fixed
condition in new designs.

Figure W-18. The Condition Node On Corner (v4) Panel displays
attributes of a Node on Corner condition.
The Node on Corner condition lets you constrain the position of a node to lie
on one of the four corners of the paper. The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
Node --- the index of the node that this condition applies to. It will only
have an effect if the node is a leaf node.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
This condition has been deprecated; you should use the Node Fixed
condition in new designs.

Figure W-19. The Condition Node Fixed (v4) Panel displays attributes
of a Node Position Fixed condition.
The Node Position Fixed condition lets you constrain the X and/or Y coordinate
of a node to a fixed value. The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
Node --- the index of the node that this condition applies to. It will only
have an effect if the node is a leaf node.
-
X Fixed to --- check this box to constrain the x coordinate
of the node. The box contains the value it is fixed to.
-
Y Fixed to --- check this box to constrain the y coordinate
of the node. The box contains the value it is fixed to.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
This condition has been deprecated; you should use the Node Fixed
condition in new designs.

Figure W-20. The Condition Nodes Paired Panel displays attributes of a
Nodes Paired condition.
The Nodes Paired condition lets you constrain two nodes to be mirror images of
one another about the line of symmetry. This condition only takes effect if the
"Symmetry" checkbox is checked in the tree inspector. The attributes shown in
the panel are:
-
Condition Index --- the index of the condition.
-
Node 1 --- the index of one of the nodes that this condition applies to. It
will only have an effect if the node is a leaf node.
-
Node 2 --- the index of the other node that this condition applies to. It
will only have an effect if the node is a leaf node.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.

Figure W-21. The Condition Nodes Collinear Panel displays attributes
of a Nodes Collinear condition.
The Nodes Collinear condition lets you constrain three nodes to lie in a
straight line. The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
Node 1 --- the index of one of the nodes that this condition applies to. It
will only have an effect if the node is a leaf node.
-
Node 2 --- the index of the second node that this condition applies to. It
will only have an effect if the node is a leaf node.
-
Node 3 --- the index of the third node that this condition applies to. It
will only have an effect if the node is a leaf node.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
The three nodes must be distinct leaf nodes of the tree.
By setting multiple such conditions, you can constrain more than three nodes to
lie in a single line.

Figure W-22. The Condition Edge Length Fixed Panel displays attributes
of an Edge Length Fixed condition.
The Edge Length Fixed condition lets you constrain an edge to a fixed length,
i.e., constrain its strain to be zero. The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
Edge --- the index of the edge that this condition applies to.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.

Figure W-23. The Condition Edges Same Strain Panel displays attributes
of an edges same strain condition.
The edges same strain condition lets you constrain two edges to have the same
strain when performing a strain optimization. The attributes shown in the panel
are:
-
Condition Index --- the index of the condition.
-
Edge 1 --- the index of one of the edges that this condition applies to.
-
Edge 2 --- the index of the other edge that this condition applies to.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
By setting multiple such conditions, you can constrain more than two edges to
all have the same strain.

Figure W-24. The Condition Path Active Panel displays attributes of a
Path Active condition.
The Path Active condition lets you constrain the positions of two nodes so that
the path between them is active (and therefore forms an axial crease in the
base). You can also specify additional constraints, forcing the path angle to
be quantized (one of a set of discrete values) or a fixed value.
The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
From Node --- the index of one of the nodes that this condition applies to.
-
To Node --- the index of the other node that this condition applies to.
-
Path Constraints --- these radio buttons let you choose whether to apply
additional constraints on the path angle:
-
Active Only --- forces the path to be active, but sets no constraint on
path angle.
-
Angle Fixed --- forces the path to be active and forces its angle to a
particular value, set in the Fix Angle text box.
-
Angle Quantized --- forces the path to be active and forces its angle
to take on a discrete value specified by the numbers in the
Quantization and Offset text boxes.
-
Fix Angle --- if the Angle Fixed button is selected, this specifies the
angle of the path, measured with respect to the x axis.
-
Quantization --- if the Angle Quantized button is selected, this specifies
the number of divisions of the full circle for angle quantization.
-
Offset --- if the Angle Quantized button is selected, this specifies
the offset angle of the angle quantization, measured with respect to the
x axis.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
Fixing the path angle and angle quantization are useful in forcing the crease
pattern to be more symmetric (and thus more easily foldable). The quantization
is defined as an integral division of 360 degrees; for example, for a path with
quantization of 4, the allowable angles would be separated by 90 degrees. The
offset specifies how the entire pattern is offset from the x axis. For
example, with an offset of 45 degrees, the allowed angles would be 45, 135,
-135, and -45 degrees.
If you use very many of these conditions, it is likely that the problem
will be over-constrained for simple optimization. More commonly, you will first
perform a simple optimization, then set a range of path active conditions and
perform a strain optimization to find the set of edge lengths that satisfies
all of the path activity conditions.
The path quantization condition should be used carefully. If you set
path quantization conditions on every active path in a pattern and don't use
the same quantization number and offset for every path, it may be impossible
to satisfy the conditions for any set of path angles, leading to a failure of
convergence.
In general, you should pick an even integer for the quantization. If you set
the quantization to an odd value, then be aware that the angle of a path depends
on which endpoint comes first in the definition of the path, so a path that
satisfies an odd quantization condition will not if its endpoints are reversed.
Make sure you really understand what you're doing before you try to apply an odd
quantization.
The Path Active condition replaces the next 3 conditions in this list, which
have been deprecated. TreeMaker will read version 4 files that contain
the old conditions, but you can only create Path Active conditions, which
combine the functionality of the version 4 conditions.

Figure W-24. The Condition Path Active (v4) Panel displays attributes
of a Path Active (v4) condition.
The Path Active (v4) condition lets you constrain the positions of two nodes so
that the path between them is active (and therefore forms an axial crease in
the base). It does not set any constraint on the path angle.
-
Condition Index --- the index of the condition.
-
From Node --- the index of one of the nodes that this condition applies to.
-
To Node --- the index of the other node that this condition applies to.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
This condition has been deprecated; you should use the Path Active
condition in new designs.

Figure W-25. The Condition Path Angle Fixed (v4) Panel displays attributes
of a Path Angle Fixed (v4) condition.
The Path Angle Fixed (v4) condition lets you constrain the positions of two nodes so
that the path between them is active and runs at a specified angle.
This is useful in forcing the crease pattern to be more symmetric (and thus
more easily foldable). The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
From Node --- the index of one of the nodes that this condition applies to.
-
To Node --- the index of the other node that this condition applies to.
-
Angle --- the desired angle, measured with respect to the x axis.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
This condition has been deprecated; you should use the Path Active
condition in new designs.

Figure W-26. The Condition Path Quantized Fixed (v4) Panel displays
attributes of a Path Angle Quantized (v4) condition.
The Path Angle Quantized (v4) condition lets you constrain the positions of two
nodes so that the path between them is active and runs at some
multiple of a specified angle. The attributes shown in the panel are:
-
Condition Index --- the index of the condition.
-
From Node --- the index of one of the nodes that this condition applies to.
-
To Node --- the index of the other node that this condition applies to.
-
Quantization --- the number of discrete divisions of the circle.
-
Offset --- the offset of the quantization angle in degrees, measured with
respect to the x axis.
-
Apply --- This button applies any changes you have made in the panel to the
tree. Changes are also applied when you hit the Enter key.
This condition has been deprecated; you should use the Path Active
condition in new designs.

Figure W-27. The Vertex panel displays attributes of a selected
vertex.
A vertex is identified by its index. The attributes shown in the Vertex panel
are:
-
Location --- the coordinates of the vertex.
None of the attributes of a vertex are editable; they are all set by
TreeMaker.

Figure W-28. The Crease panel displays attributes of a selected
crease.
A crease is identified by its index and by the indices of the two vertices
at each end of the crease. The attributes shown in the Crease panel are:
-
Kind --- the structural role played by the crease within the crease pattern:
one of axial, gusset, ridge, folded hinge, unfolded hinge, or pseudohinge.
-
Fold --- the fold status of the crease within the crease pattern: one of
mountain, valley, flat (unfolded), or border (on the boundary of the
creased region).
-
Crease Angle --- the angle of the crease in degrees relative to the
x axis.
None of the attributes of a crease are editable; they are all set by
TreeMaker.

Figure W-29. The Facet panel displays attributes of a selected facet.
A facet is identified by its index. The attributes shown in the Facet panel
are:
-
Color --- whether the white or colored side of the paper is facing up in the
folded form.
-
Centroid --- the coordinates of the centroid (center of mass) of the facet.
-
Vertices --- the indices of the vertices that are the corners of this
facet, taken in counterclockwise order.
-
Creases --- the indices of the creases that are the sides of this facet,
taken in counterclockwise order.
None of the attributes of a facet are editable; they are all set by
TreeMaker.

Figure W-30. The Group Panel is displayed when you have multiple parts
selected.
The Group Panel is displayed when you have selected multiple parts. It shows
the number of each type of part selected and the indices of the selected parts.
The Folded Form window is a floating window that displays a silhouette of the
folded form if a crease pattern has been fully computed. If the crease pattern
is not fully computed, this window will show nothing. The Folded Form window is
toggled on and off with the View->Show Folded Form/Hide Folded Form command.

Figure W-31. The Folded Form window displays a silhouette of the
folded form of the base computed by TreeMaker.
The Folded Form window shows the folded form as an x-ray view; that is, all
creases are shown, even if they would be hidden by layers of paper. All creases
are shown with AGRH coloring; that is, axial creases are shown in black, gusset
creases in gray, ridge creases in red, and hinge creases in blue.
It always shows the entire base; if you resize the window, the image scales to
fill the window. So the size of the folded form image is generally not related
to the size of the crease pattern image.
The Folded Form window is for display only; clicking in it will do nothing.
However, if you select a vertex, crease, or facet in the main window, it will
be shown highlighted in the folded form window. Furthermore, if you select an
edge of the tree in the main window, its corresponding flap (consisting of all
associated facets) will be highlighted in the Folded Form window.
When the document is printed, the second page of the printout will contain an
image of the folded form, if the folded form exists and the Folded Form window
is shown. If the Folded Form window is hidden, only the Design window will be
printed.
The View Settings window is a floating window that controls the display
of parts in the main window. It lets you turn on and off which parts are
displayed and affects how they are displayed.

Figure W-32. The View Settings window displays various settings that
affect what is shown in the Design Window.
The View Settings window contains six preset buttons that turn on and off
various groups of settings, and nine groups of settings that affect how
individual parts are displayed.
View Settings: Presets

Figure W-33. There are six buttons for preset combinations of view
settings.
There are six preset buttons at the top of the window that turn on and off
various groups of settings. These presets, and their function, are as follows:
-
All --- turns on all view settings. This is usually too busy for any but
the simplest of designs.
-
Tree --- turns on just those settings that affect the tree display: nodes,
edges, and their associated conditions. This is the most useful setting
when you are first putting the tree together.

Figure W-34. The Design Window with Tree preset view settings.
-
Design --- an all-purpose view, and the default view when the program starts
up. This will show selected information about the tree, polys, some paths,
and creases, when the crease pattern is constructed. Typically one will
work mostly with the design presets turned on, then switch over to crease
or plan presets once the crease pattern is fully constructed.

Figure W-35. The Design Window with Design preset view settings.
-
Creases --- shows just the crease pattern.

Figure W-36. The Design Window with Creases preset view settings.
-
Plan --- shows the crease pattern, plus the coordinates of important
vertices. This is the most useful view for transferring a pattern to
another sheet by measuring and marking, or for keeping a physical record of
a crease pattern.

Figure W-37. The Design Window with Plan preset view settings.
-
None --- turns off all view settings. This is most useful when you only
want to see one or two types of information. Click the None button to turn
everything off, then turn on just the objects you want to examine.
Each type of part has a characteristic color scheme and graphical
representation. The representation of each part and the individual groups of
settings that affect that representation are described in the following
sections.

Figure W-38. The Nodes group in the View Settings window.
A node represents an endpoint of the initial tree and is drawn as a black dot
with optional text giving its coordinates and other characteristics.
The Nodes group of settings affects how nodes are displayed in the Design
window. The controls are:
-
All --- turns on all settings.
-
None --- turns off all settings.
-
Leaf Nodes --- display leaf nodes, which are tree nodes with one incident
edge
-
Branch Nodes --- display branch nodes, which are tree nodes with two or more
incident edges
-
Sub Nodes --- display nodes that are not part of the tree but that are
constructed in the interior of polys as part of the universal molecule
construction, i.e., inset nodes.
-
Dots --- display a dot for each visible node.
-
Circles --- display a circle around each visible leaf node with a radius
given by the length of the incident edge. This is the circle that arises in
circle-packing.
-
Indices --- show the index of each visible node.
-
Coordinates --- show the x and y coordinates of each
visible node.
-
Elevation --- show the elevation of each visible node, which is the distance
from the axis in the folded form of its associated vertex.
-
Depth --- show the depth of each visible node, which is the distance along
the axis from the root node in the folded form of its associated vertex.
-
Labels --- show the label of each visible node.
-
Flags --- show various flags on each visible node. Each possible flag is
indicated by a letter; capital letters indicate a flag that is set, lower
case indicates a flag that is unset.

Figure W-39. The Edges group in the View Settings window.
An edge represents a flap in the base and is drawn as a light blue line
connecting two nodes, along with a dot near its midpoint and optional text
describing some of its attributes. If an edge is pinned (its length cannot be
changed without causing a path constraint to be violated), it is drawn in a
lighter shade of blue.
The Edges group of settings affects how edges are displayed in the Design
window. The controls are:
-
All --- turns on all settings.
-
None --- turns off all settings.
-
All Edges --- turns on/off the display of all edges independently of the
other settings in this group.
-
Dots --- display a dot on each visible edge.
-
Lines --- display a line for each visible edge connecting its nodes.
-
Indices --- display the index of each visible edge.
-
Lengths --- display the length of each visible edge.
-
Strain --- display the strain and strained length of each visible edge.
-
Labels --- show the label of each visible edge.
-
Flags --- show various flags on each visible edge. Each possible flag is
indicated by a letter; capital letters indicate a flag that is set, lower
case indicates a flag that is unset.

Figure W-40. The Paths group in the View Settings window.
A path represents a distance relationship between two leaf nodes on the tree
and their two corresponding vertices on the paper. A path is drawn as a
straight line connecting the two relevant nodes. There are paths between all
pairs of leaf and/or branch nodes, but only the leaf paths -- paths between
leaf nodes -- correspond to meaningful distance relationships.
Because there are so many paths, generally only a subset of paths will be
shown. Paths are drawn in one of three colors:
-
Red --- for invalid paths, paths for which the corresponding leaf nodes are
too close together;
-
Amber --- for valid paths, paths for which the corresponding leaf nodes are
sufficiently far apart;
-
Green --- for active paths, paths for which the corresponding leaf nodes
are exactly separated by their minimum distance.
Paths can also be displayed with optional text describing some of their
attributes including their associated distance condition and various flags.
The Paths group of settings affects how paths are displayed in the Design
window. The controls are:
-
All --- turns on all settings.
-
None --- turns off all settings.
-
Leaf Paths --- turns on/off the display of leaf paths, which are tree paths
that run between two leaf nodes.
-
Branch Paths --- turns on/off the display of branch paths, which are tree
paths that have a branch node at either end.
-
Sub Paths --- turns on/off the display of sub paths, which are paths that
have a subnode at either end, i.e., paths that are created as part of the
construction of the universal molecule.
-
Active Paths --- turns on the display of active (leaf) paths, independent of
other checkboxes.
-
Border Paths --- turns on the display of border paths, i.e., the paths that
make up the convex hull of the nodes.
-
Polygon Paths --- turns on the display of polygon paths, which are paths
that make up the polygon network (most active paths and border paths).
-
Invalid Paths --- turns on the display of invalid paths, paths whose tree
constraints are violated, independent of other checkboxes.
-
Dots --- display a dot on each visible path.
-
Lines --- display a line for each visible path connecting its nodes.
-
Indices --- display the index of each visible path.
-
Lengths --- display the lengths (both minimum and actual) of each visible
path.
-
Flags --- show various flags on each visible path. Each possible flag is
indicated by a letter; capital letters indicate a flag that is set, lower
case indicates a flag that is unset.

Figure W-41. The Polys group in the View Settings window.
A poly represents a universal molecule, i.e., a portion of the crease pattern
that folds flat with its boundary lying on a single line: the axis, if it is
a major polygon, or a line parallel to the axis, if it is a sub polygon. A poly
is drawn as a pale orange polygon, outlined by slightly darker lines and with
a dark dot at its centroid. The polygon, lines, and/or dot can be individually
turned on and off with the settings described below.
The Polys group of settings affects how polys are displayed in the Design
window. The controls are:
-
All --- turns on all settings.
-
None --- turns off all settings.
-
Tree Polys --- turns on/off the display of tree polygons, each of which
contains a single universal molecule.
-
Sub Polys --- turns on/off the display of subpolygons, which are reduced
polygons within universal molecules that are part of the recursive
construction of the universal molecule.
-
Dots --- display a dot on each visible polygon at its centroid.
-
Lines --- display an outline of each visible polygon.
-
Fills --- display a yellow fill for each visible polygon.
-
Indices --- display the index of each visible polygon.
-
Flags --- show various flags on each visible polygon. Each possible flag is
indicated by a letter; capital letters indicate a flag that is set, lower
case indicates a flag that is unset.

Figure W-42. The Vertices group in the View Settings window.
A vertex is a point where creases come together within the crease pattern. A
vertex is displayed as a black dot with optional text describing some of its
attributes.
The Vertices group of settings affects how vertices are displayed in the Design
window. The controls are:
-
All --- turns on all settings.
-
None --- turns off all settings.
-
Major Vertices --- turns on/off the display of vertices with 3 or more
incident creases.
-
Minor Vertices --- turns on/off the display of vertices with 2 or fewer
incident creases.
-
Dots --- display a dot on each visible vertex at its centroid.
-
Indices --- display the index of each vertex polygon.
-
Coordinates --- display the x and y coordinates of each
visible vertex.
-
Elevation --- display the elevation of each visible vertex, which is the
distance in the folded form from the axis of the base.
-
Depth --- display the depth of each visible vertex, which is the distance in
the folded form along the axis from the root node vertex.
-
Discrete Depth --- display the discrete depth of each visible vertex, which
is the number of hops along the tree from the root node to the tree node of
this vertex. If this vertex does not have a tree node (e.g., it is part of
a pseudohinge), (-1) is displayed instead.
-
Tree Nodes --- display the tree node (if any) that is the tree projection of
this vertex.
-
Flags --- show various flags on each visible vertex. Each possible flag is
indicated by a letter; capital letters indicate a flag that is set, lower
case indicates a flag that is unset.

Figure W-43. The Creases group in the View Settings window.
A crease represents a fold line in the crease pattern. (However, any given
crease may be flat, i.e., unfolded.) A crease is drawn as a line connecting its
two vertices, plus a dot near its midpoint along with optional text describing
some of its attributes.
Creases can be drawn with two different color schemes, described below.
The Creases group of settings affects how creases are displayed in the Design
window. The controls are:
-
All --- turns on all settings.
-
None --- turns off all settings.
-
Major Creases --- turns on/off the display of major creases, which are
axial, gusset, and ridge creases.
-
Minor Creases --- turns on/off the display of minor creases, which are hinge
and pseudohinge creases.
-
Dots --- display a dot on each visible crease.
-
Lines --- display a line for each visible crease connecting its vertices.
-
Coloring --- select the color scheme used for creases. The two possible
schemes are:
-
AGRH Coloring --- creases are distinguished by their structural role,
as follows:
-
Axial Creases --- black
-
Gusset Creases --- gray
-
Ridge Creases --- red
-
Hinge Creases --- blue
-
Pseudohinge Creases --- cyan
-
MVF Coloring --- creases are distinguished by their fold direction, as
follows:
-
Mountain Creases --- black
-
Valley Creases --- magenta, dashed
-
Flat (unfolded) Creases --- light gray
Note that there are situations where TreeMaker cannot
compute the MVF crease assignment; in such cases, all creases will be
shown as Flat under MVF coloring. AGRH coloring is always available, and
in many cases you will still be able to find a valid crease assignment by
hand, using these rules of thumb:
-
Ridge creases are always valley folds.
-
Gusset creases are always mountain folds.
-
Pseudohinge creases are always mountain folds.
-
Axial creases are almost always mountain folds.
The exceptions to the "almost always" can usually be found by trial and
error.
-
Indices --- display the index of each visible crease.
-
Flags --- show various flags on each visible crease. Each possible flag is
indicated by a letter; capital letters indicate a flag that is set, lower
case indicates a flag that is unset.

Figure W-44. The Facets group in the View Settings window.
A facet is a polygonal region of the crease pattern outlined by creases. A
facet is drawn as a filled polygon in one of two shades of purple with a dot
at its centroid and optional text describing some of its attributes. It is also
possible to overlay the facets with a representation of the facet ordering
graph, which describes the overlap order between adjacent facets, and from which
the relative order of any two overlapping facets may be inferred.
The Facets group of settings affects how facets are displayed in the Design
window. The controls are:
-
All --- turns on all settings.
-
None --- turns off all settings.
-
All Facets --- turns on/off the display of facets, independent of other
checkboxes.
-
Dots --- display a dot on each visible facet at its centroid.
-
Arrows --- display the arrows that describe the ordering among facets.
These arrows constitute the "facet ordering graph." The order of any two
overlapping facets may be determined from the unique direction of any path
between the two facets in the facet ordering graph. If there is no directed
path between two facets in the facet ordering graph, then the two facets do
not overlap in the folded form.
-
Fills --- display a colored fill for each visible facet. The fill is one of
two shades of purple, which are relevant if the base is folded from
conventional two-colored origami paper (that has a white and a colored
side). The lighter shade indicates that the facet is white side up in the
folded form; the darker shade indicates that the facet is colored side up
in the folded form.
-
Indices --- display the index of each visible facet.
-
Order --- display the order index for each visible facet. In a well-formed
crease pattern, there is a total ordering on the facets, so that the
relative order between any two facets may be computed in constant time by
comparing their order indices.
-
Corridor Edge --- display the index of the edge whose flap this facet is a
part of.
-
Flags --- show various flags on each visible facet. Each possible flag is
indicated by a letter; capital letters indicate a flag that is set, lower
case indicates a flag that is unset.

Figure W-45. The Conditions group in the View Settings window.
A condition represents a geometric relationship imposed on nodes, edges, and/or
paths by the user above and beyond the requirements of the path conditions.
Conditions are represented in different ways, depending on what objects they
affect, but a common feature is a dot connected by a short flag to a node,
edge, or group of nodes connected by lines. Conditions come in two colors:
light red, if they are not currently feasible (i.e., not currently satisfied),
or light purple if they are currently feasible.
The Conditions group of settings affects how conditions are displayed in the
Design window. The controls are:
-
All --- turns on all settings.
-
None --- turns off all settings.
-
Node Conditions --- turns on/off the display of conditions that are set on
nodes.
-
Edge Conditions --- turns on/off the display of conditions that are set on
edges.
-
Path Conditions --- turns on/off the display of conditions that are set on
paths.
-
Dots --- display a dot for each visible condition. The dot is placed close
to the affected parts.
-
Lines --- display lines connecting the condition dot to the nodes,
edges, and/or paths that are affected by the condition.
-
Indices --- display the index of each visible condition.
-
Types --- display a word indicating the type of condition that is set on the
part.

Figure W-46. The Paper group in the View Settings window.
The Paper group of settings affects how the paper is displayed in the Design
window. The controls are:
-
Symmetry --- display the line of symmetry on the paper.

Figure W-47. The Help window.
The Help window is brought up if you click the Help->Help menu command.
The window is resizeable and searchable, and there is a table of contents bar
along the left side. You can also print each of the major help sections by
clicking on the printer icon within the window, if you would like a hard copy
of this documentation.
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