##### New

This submenu opens the window of creation of auxiliary lines. The auxiliary lines and auxiliary points (an auxiliary line is nothing more than an orderly succession of auxiliary nodes) are objects that are not part of the structure. They are drawn with a orange and we serve as a reference for the structure.

We can use them as:

- Points where to begin or end a geodesic line.
- Points where to drag other points of the structure, as is done in the form finding state.
- To create apex rings.
- Or simply as reference data.

There are different types of auxiliary objects: Line, Arc, Circle, Point, Apex ring, Parabola, Polyline

**Line**

An auxiliary line is determined by its two endpoints. We can define them in three ways:

- By directly entering the coordinates X, Y, Z of these points in the corresponding
**From**and**To**boxes. - We mark the box with a mouse click. Then selecting the node with the mouse automatically fills boxes X,Y,Z of the node and number of the selected node appears on the right side.
- Doing what we have just discussed in the method 2 and manually modifying the values of the node (for example using the X,Y coordinates but with a different Z ). In this case, we see that the number of the node we originally selected on the right disappears, since now it is not the same node.

Once, start and end nodes are defined, we modify the value of the **number of parts** to split the auxiliary line that we are going to create. (10 is the default value)

**Arc**

An auxiliary arc is determined by its two endpoints and an interior point. We can define them in three ways:

- By directly entering the coordinates X, Y, Z of these points in the corresponding boxes of
**From**,**Interior point**and**To**. - We mark the box with a mouse click. Then selecting the node with the mouse automatically fills boxes X,Y,Z of the node and number of the selected node appears on the right side.
- Doing what we have just discussed in the method 2 and manually modifying the values of the node (for example using the X,Y coordinates but with a different Z ). In this case, we see that the number of the node we originally selected on the right disappears, since now it is not the same node.

Once start, interior point and end points are defined, we modify the value of the **number of parts** to split the auxiliary arc that we are going to create. (10 is the default value).

**Circle**

An auxiliary circle is determined by its three points: one initial and two others who by similarity to the arc we call them as endpoint and interior point. We can define them in three ways:

- By directly entering the coordinates X, Y, Z of these points in the corresponding boxes of
**From**,**Interior point**and**To**. - We mark the box with a mouse click. Then selecting the node with the mouse automatically fills boxes X,Y,Z of the node and number of the selected node appears on the right side.
- Doing what we have just discussed in the method 2 and manually modifying the values of the node (for example using the X,Y coordinates but with a different Z ). In this case, we see that the number of the node we originally selected on the right disappears, since now it is not the same node.

Once start, interior point and end points are defined, we modify the value of the **number of parts** to split the auxiliary circle that we are going to create. (10 is the default value).

It is important to keep in mind that the circle is divided into an integer number of segments. This means that only the starting point is part of the circle. That is, it matches one of the auxiliary points that form the circle. In any case, if the interior point and the endpoint matches, it is a coincidence.

**Point**

If you select the **Point** option, a message will appear in the window and the cursor becomes selection.

From this moment, we can mark with the mouse on any bar in the structure and a new auxiliary node (in orange color) appears just at the marked point. We can create as many auxiliary point as we want or we deem appropriate.

**Apex ring**

This is perhaps the auxiliary line which is more complicated to explain, but at the same time one of the most useful. It draws a circle, but unlike the previous case, this circle not passing through three points but represents the typical apex ring that is usually placed in the upper part of the conoids.

The first point that we have to set is the * Center *of the ring. Usually it doesn’t coincide with the highest part of a mast, but is situated a little further down, such as point A of the figure. We can create his point manually or by using auxiliary point.

Then, we mark the foot of the mast (the * bottom *of the line). In fact, what we are doing is to specify the point B so that the segment AB is perpendicular to the plane of the circle that we are going to create. Therefore A and B can not be the same point.

Then we mark the point C as * Reference*. The apex ring is created using a set of segments, as many as indicated by

*in the box at the bottom. The point C is used to indicate where this set of segments starts. For this reason, the plane of triangle ABC cuts the apex ring just at a point. This will be the point where we begin to plot the set of segments.*

**number of parts to divide**Finally, we set the diameter of the apex ring (in m) and the number of segments that form the ring.

**Parabola**

A parabola, like an auxiliary arc, is determined by its two endpoints and an interior point. We can define them in three ways:

- By directly entering the coordinates X, Y, Z of these points in the corresponding boxes of
**From**,**Interior point**and**To**.

Once start, interior point and end points are defined, we modify the value of the **number of parts** to split the auxiliary parabola that we are going to create. (10 is the default value).

It is important to keep in mind that the parabola is divided into an integer number of similar segments. This means that the inner point that has served to create the parabola may not be one of the nodes that define the parable.

**Polyline**

A Polyline is a broken line that joins different points. These points are any of the existing ones on the screen, are points of the membrane, points geodesic line or auxiliary points.

As we go by clicking on the nodes, these nodes appear one by one in the box on the right. If we want to insert some node or delete, we should click on the node in the box. This will display the menu “Insert before | Insert after | Delete”. If you want to modify a node, remove it first and then insert the new.

##### Edit

By pressing this submenu, we can select any auxiliary line with the mouse and get the same window that we have used for its creation. Then, we can modify the endpoints, the central point, the number of parts, etc. This is a very useful option when we want to check a given auxiliary and adjust it to our desire.

If the line auxiliary was created with an older version it may not be possible to edit (see image on the right).

##### Info

By pressing this submenu, we can select any auxiliary with the mouse and get a basic information about it:

- Auxiliary number
- Type
- Number of segments that the auxiliary is divided into
- Total length (sum of each of the straight segment that form the auxiliary)

##### Delete by numbers

Pressing this submenu displays the dialog box that asks us the numbers of auxiliary lines we want to delete. We can use the comma dash code:

1,2-5,9 equals to 1, 2, 3, 4, 5 and 9.

##### Delete graphically

Through this menu, the mouse cursor changes to selection finger so that we can delete the auxiliary lines by pressing the left mouse button on the auxiliary line we want to delete.

##### Delete auxiliary nodes

When we create an auxiliary line (arc line, circle, … ), we create auxiliary points. Deleting the line deletes these auxiliary points. However, if we directly created auxiliary points, we need a command to be able to delete them and this is precisely what this submenu does.

##### Import DXF

Using this submenu, we can open a DXF file and import the majority of the entities of this file. It must be kept in mind that WinTess3 imports only entities. So all the entity groups that exist in the DXF should be exploded.

At the moment only these can be imported: LINES, 2D and 3D POLYLINES, POINTS and 3DFACES.

In the near future, importing arcs and circles is also expected as broken down into polylines.

##### Auxiliary lines -> Rigid bars

We have already seen in the section of form finding that we could use the auxiliary lines to form an arc. Well, often after using this auxiliary arc, we want to transform it into a true structural arc. As this is very common, this submenu has been created to perform this task automatically.

As indicated the pop-up note, we click on the auxiliary line that we wish to make rigid bar, and see how it turns to blue indicating that it is now a set of rigid bars forming a group. Immediately, we open the editing window of bars so that we can define the tube that form these rigid bars.

##### Bezier boltropes

This submenu generates curves similar to ropes through auxiliary lines (all formed by a set of auxiliary points). It draws a Bézier curve where the reference points are the points that make up the boltrope (cable edge). The **Bézier curve** does not pass through the original points but it is always inside the concavity form the boltrope. We can plot the **Bézier curve** with any number of points we want.

This option can be used in the state of patterning to obtain patterns smoother at the perimeter.

##### Pull mesh

With this menu, we can move a mesh (only in the state of Form finding) to attach to an auxiliary line. The most common case (but not the only one) is to adapt a mesh to arch or a parabola created previously as an arc or parabola type of auxiliary line.

In the tutorial How to generate a cover of two crossed arcs, we see a concrete implementation of this menu.