Stitch Era - vector graphics

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1 Introduction

This is a beginner's tutorial for the Stitch Era embroidery software. It explains how edit and/or create vector graphics that later could be translated to embroidery objects (stitch sections).

Tutorial home page
Stitch Era embroidery software
Learning goals
Be able to import vector graphics from a third party program
Be able to draw
Be able to edit/tune existing drawings

Prerequisites:

Materials
none

Concurrent steps:

Next steps:

Quality and level
This text should technical people get going with Stitch Era. I use it an optional master degree course in educational technology.

There are four reasons for learning how to use vector graphics:

  • Repair/adjust vectorized bitmap (raster) images
  • Work with imported vector graphics (as opposed to use the original source program). Personally I get most of my vector graphics from openclipart.org
  • Draw vector art with Stitch Era
  • In addition, you will become familiar with vector drawing terminology and techniques. You also will need these for stitch section tuning and direct stitch object drawing. The controls are slightly different and more complex, but the drawing/editing principles remain the same !

Vector graphics are translated fairly easily into embroidery objects (stitch sections), e.g. through the To embroidery / Art to Stitch auto-digitizer and this is why we favor the "vector drawing first" route as opposed to directly drawing stitch objects. Of course, the various design use cases can be combined in a project (also read the corresponding chapter in the Stitch Era embroidery software##Some_use_cases_of_Stitch_Era introductory article.

Let us insist that same logic applies if you want to manipulate or directly create embroidery objects (stitch sections). The difference between vector graphics (as it exists in more advanced form in programs like Illustrator, Corel Draw, or the free Inkscape) and "stitch object graphics" is that the latter is much less visual and much more complex, since it includes visualization of stitch patterns, stitches, etc. I believe that embroidery specialists probably don't do much vector graphics, i.e. they probably can "see" how stitch sections will render. I can't (for now). Top notch professionals actually sometimes don't even seem to work with high-level embroidery objects, i.e. they create embroidery sections stitch by stitch on high expense projects. A beginner just should be able to adjust stitch sections, i.e. be able to understand how to manipulate nodes and curves a bit. These operations are easier to learn with "normal" vector graphics.

2 Creating vector graphics in the Artwork module

When you start a new empty project you will find yourself automatically in the HOME section. In order to import or draw vector graphics, select the ARTWORK tab as shown in the following picture.

Artwork tab - empty design

At this point, you either can import artwork, e.g. like discussed in Stitch Era - creating embroidery from vector images or start drawing. Several kinds of drawings can be created an in different ways, for example:

  • Insert pre-built closed shapes
  • Insert pre-build open shapes
  • Draw shapes with Bezier curves
  • Draw shapes free-hand
  • Draw letters with the text tool (not to be confused with the lettering module that directly will create stitch sections)

Let's insert an ellipse, i.e. a close shape, as shown below. Select the ellipse icon from the Closed shapes pull down menu, then move the mouse into the work area below and drag it.

Stitch Era 17 - Artwork tool - creating a circle

If you aim to create a circle, there are three solutions:

  1. Hold down the CTRL key while you drag out the mous
  2. Watch the dimensions at the bottom of the Stitch Era screen.
  3. Draw an approximate object and then edit it's properties later by clicking on the layout tab (this how I work).

After you inserted a first vector object or when you select vector object, the interface will change and display the full tool set.

Firstly, you may want to change colors. Play with "Fill color" and "Border color" that you should see in the menu on top, as you can see in the figure below. You also may notice the "Layout" tab in the top menu. It would allow you to change the size, position and rotation of the object and align/distribute several objects. More about this later.

Stitch Era 17 - Artwork tool / Vector tool - vector object created and selected, change thickness or border

If you open the Artwork / Layout tab, you can change things like position and size.

Stitch Era 17 - Artwork tool / Layout tool - vector object created or selected. change dimensions

In older version, the interface was different, e.g. there was only one vector tab as you can see in the following screen shot.

Stich Era 11 (2001) - Artwork tool - vector object created or selected

Now let's have look at basic properties of vector objects, i.e. fill and border

3 Anatomy of vector objects

3.1 fills and borders

Vector objects like circles are made of two parts:

  • The border (also called outline, stroke or line)
  • The fill (also called the body or paint or inside)

In the format tab, by selecting one of the rectangles (see fig. below) you can select whether you want

  • a fill-only object (Vectors-only body), i.e. the border is made invisible
  • a stroke-only object (Vectors-only outline), i.e. the shape is made invisible
  • an object that has both (Vectors outline + body), i.e. you will see both a shape and its border
Three kinds of vector objects (shapes): Fill-only, stroke-only, fill+stroke

In embroidery (as well as in other multi-media projects) you will work with all three.

3.2 The envelope

Each vector object is defined by global size and position, i.e. the so-called envelope.

The grey envelope controls (little square dots) define the size of the object and allow to change it's height and width. Move your mouse precisely over one of the squares in a corder or in between and drag with the mouse (press and hold). Play with that a bit, it should be easy to understand.

Then click on the Layout tab and observe the changes in the the Size ribbon panel.

Change the width by dragging an envelope control

Warning: As you shall learn just below, the vector object itself is defined by other control points and sometimes it's difficult to select the envelope points. Read on....

4 Manipulation of vector shapes

We now shall systematically introduce the most frequent vector shape manipulation procedures. I.e. we will look at what is inside the envelope.

4.1 Shape and shape adjustments of vector objects

Since borders are not defined by pixels but by control points, vector objects are scalable upwards or downwards. A drawing will remain the same whether it has the size of a bed linen or a shirt pocket or a football field.

The shape of a vector object is defined by its outline (border/stroke/etc), or more precisely by so-called control points or nodes that will define the exact path of the border. Control points are either white or cyan.

In order to change the shape of an object, there are two methods as we shall explain in more details later:

  • You can move the control points. Just drag them with the mouse
  • You can adjust the curves connecting to the next nodes through handles which are represented as small little pink points. Click on a node, then drag the pink points.

Important tip:

  • Pre-built shapes (e.g. an ellipse) must be converted to vector objects first (use the right click context menu). A vector object is defined by nodes and connecting segments (lines).

In Stitch Era, there are different kinds of vector nodes. The way they connect to neighboring nodes are defined by three properties (parameters) that one can change in the Nodes ribbon panel or through the context menu (right-click) of a node.

  1. Straight / curved sides. A straight node (point) will have a straight line to the nodes before and after the path defining the outline or simple stroke. Curved nodes have curved lines (segements) to the nodes before and after (unless one of these nodes is a straight node). Straight nodes show as rectangles.
  2. Normal / corner node. Normal node (similar to Adobe's "smooth points") are white and connect two curved segments in a smooth way, i.e. the node sits in the middle of a line. Corner nodes define cornes and are shown as filled cyan nodes.
  3. Symmetric / uniform node. Symmetric and uniformed nodes are not visually distinguishable. Uniform nodes allow to manipulate both segments independently, whereas segments of symmetric nodes affect each other so that they keep the same angle.

The following screen capture shows a mushroom being designed. Its hat is modeled with normal nodes, the stem with corner nodes and the bottom with straight nodes.

Changing the curves

In order to change the curves connecting to a node, click on the node first. Then play with the following:

  • Move the pink curve controls near or far to get a sharper or smoother curve.
  • Rotate the same controls around the node to change concavity (direction).

As explained above, you also may want to change the node type. I.e. if you only wish to change the curve on one side of a node, the node must be a uniform node and not a symmetrical one.

Vector nodes (controls) and curve control handles

4.2 Deleting nodes

1) Deleting a single node

For deleting a single node:

  • Select a node. Make sure to select a white or cyan vector shape control node and not just one of the grey envelope controls that define the size of the object (see above). Most shape control nodes then will also show curve control handlers ... i.e. one or two little pink circles.
  • Right click (context menu) and select delete or hit the delete key

Warning, before you decide to use the quicker delete key method, you should be aware that sometimes you will fail to select a node. Instead you may have selected the whole vector object instead and then kill the whole object. Hit CTRL-Z to get it back.

After deleting a node, you probably will have to adjust the curves.

2) Mass deletion of nodes

  • You can select nodes located in different places by holding down the CTRL key
  • You can select a sequence of nodes by selecting the first, then selecting the second (end of the sequence) holding down the SHIFT key.

That kind of operation is often required after vectorizing a bitmap image. The following picture shows to the left a kind of ragged rectangle that in reality should be stitched as smooth rectangle. Of course, you just could delete this one and draw your own, but this may not be the easiest option for a path that would represent a person for example.

In order to smooth out vector graphics, you should follow and adapt a procedure like this:

  • Decide with nodes you want to keep.
  • Transform each of the nodes if needed. Typically you will get normal nodes from a vectorizing process and must turn some into either corner nodes or straight nodes.
  • Then kill all the nodes in between and adjust curves

In the example below we transformed four nodes near the corners into straight nodes and then fixed the left side by selecting all the in-between nodes (SHIFT key) and hitting DEL.

Deleting a sequence of nodes

If you want to delete a sequence of nodes you also can just hit delete several times in a row. Deletion will happen in the direction of the more recent added node.

By the way:

  • You also can perform other operations to a sequence of selected nodes, e.g. turn all nodes into straight nodes. Explore the context menu !

4.3 Auto-trimming shapes

There is an auto-smoothing procedure available in the Combine Vectors ribbon panel.

  • Select at least two objects, else it won't work. If you only have a single object just insert some random thing and then delete it later
  • Then select Trim Shapes in the Combine Vectors ribbon panel on top.
  • Each time you click, objects will be further trimmed. However, you never can agressively trim like you could in a program like Illustrator. In the picture below I clicked about 10 times on trim shapes and the original shape is pretty much preserved.
Trimming vectors

Warning: Trimming a lot of shapes takes a lot resources and Stitch Era (even version 17) may crash. Therefore we suggest selecting smaller of groups of vectors for trimming. E.g. all of the same color.

4.4 Inserting a node

In SEU, inserting a node means adding a node within a curve between the currently selected node and the prior node.

Adding a node is different operation (see below)

To insert a node:

  • Select a node. In the picture below we selected the lowest left one.
  • Right-click to access the context menu: You now can delete, insert and add

In a corner, it may be difficult to select a shape control node. You are likely to select an envelope node that defines the overall size and rotation of the object. You may have to click twice. If you still can't select your corner node, then just drag the node inwards/upwards so that it won't fit into the corner. Drag it back later.

Inserting a node

Once you added nodes, you then can:

  • Move each node into position.
  • Change type if needed, e.g. in picture below I transformed a normal node into a corner node. Alternatively you also could select the appropriate node type, before you insert it. Use the Nodes menu
  • Drag out / rotate the curve controls.
Adjusting a curve after inserting a node

Tip: Adding less nodes is better. E.g. to draw a simple "hill" you only need to nodes. Use the curve controls to draw the hill.

Simple hill shape defined with just two nodes and the right curves

4.5 Adding a node

Adding a node refers to a process where you can add and place nodes. The principle is similar as for inserting a node.

  • Decide what kind of nodes you plan to insert, i.e. typicially you would choose curved, normal and uniform nodes (Nodes menu on top)
  • Select a node in your vector object.
  • Right-click and select add node from the context menu
  • You now can directly position the new node (Click)
  • You then can add a next node and so forth
  • Hit ESC if you are done

Since I never know in which direction the node will be inserted (i.e. it's possible to tell what is "before" or "after", I often have to change the selected node. Just hit ESC and then get the other one when you see that adding is done in the wrong direction...

4.6 Changing size and rotation

A vector object is globally defined by its width, height, rotation and position. All of these can be manipulated through the eight grey rectangular controls that sit on the so-called bounding box or envelope rectangle.

Changing size

  • Resizing an object uniformly: Drag one of the four corner points
  • Resizing an object's height or width: Drag one of the four grey points in the middle
Changing the width of a sailing boat

Changing rotation

  • Changing the rotation: Hold down the CTRL key and drag clockwise or counter-clock wise a grey point in one of the corners. By default the object will turn around a point that sits in the center, i.e. the so-called rotation point.
  • Changing the rotation point: Hold down the CTRL key and move the light grey little circle that originally may be in the center to a new position.
Rotation around a center point that is at the bottom

Change size using the layout tool:

  • Size (both direction) or height and width also can be changed using the Layout tool, i.e. change values to the left.

Let's have a look at an example. Let's assume that you have an ellipse that you would like to transform into perfect circle.

  • Draw an ellipse first with the Closed Shapes tool
  • Select the layout tool
  • Adjust with the Size panel
Creating a perfect circle with the layout tool

5 Free hand drawing

The FreeHand tool allows to create all four vector object types:

  • shapes only
  • outlines only (closed pathes)
  • lines (pathes)
  • shapes + outlines

To create a free hand object:

  • Click on the FreeHand tool
  • Then set the type of drawing, i.e. pick the right rectangle (Only Body, only outline, or outline+body) in the Format Tab.

Closed vs. open pathes (i.e. shapes vs. lines): A figure becomes closed when the end point (where you release the mouse) is very close to the starting point

The Create Perfect Figures option:

  • TheFreeHand tool has a little pulldown menu that allows you to draw smoother figures, i.e. drawings that have less control points and simpler curves. Tick this option and try.

The following screen capture shows a perfect cloud (well, with respect to my drawing skills) made with the FreeHand tool and the following options:

  • Create Perfect Figures = on,
  • vectors outline + body = ticked
  • Fill Color = light grey
  • Border Color = dark grey
Stitch Era FreeHand drawing tool

Of course, you now could make adjustments in several ways:

  • Drag nodes
  • Adjust curves with the curve control handlers (click on a node first). You may to transform a node into a different type (e.g. a normal node into a corner node using the Nodes panel)
  • Add / Insert new nodes
  • Add new drawings.

6 Drawing vector objects with Bezier curves

The Bezier tool allows to create technical drawings, i.e. both vector objects with fills and simple vector path. Below, we shortly will introduce the basics. At some point we should expand this section and explain more ....

Common principle:

  • Select the Bezier tool first
  • Either click or drag the mouse
  • To abort drawing: ESC
  • To finish a drawing: Right-click, then choose either
    • accept to create a polyline (i.e. a line that is not closed)
    • close Shape to create a polygone. Depending on your choices in Format tab, the result will be filled, not filled or filled with a border. Clicking on an other node will have the same effect.
    • close with mirror shape
    • abort to abort (same as ESC)

6.1 Creating a shape with straight lines

  • Select the Bezier tool
  • Insert nodes by clicking on each position in the path: click ... click ... click
  • Then, right-click -> Close shape
Creating straight lines

If you don't get the shape right, don't worry. You always can change it by changing the node types and by adjusting the curves, as explained prior in this tutorial...

6.2 Creating a shape with straight lines and curves

Principle:

  • To insert straight lines, proceed as above
  • To create a curve, don't click, but hold down the mouse and drag, e.g in the following little example we did:
    • click ... click .... mouse-down+drag .... drag ... right-click->close

The first mouse-down+drag was positioned on top in the middle between the two first points.

Creating normal nodes with curves

6.3 Creating a shape with straight lines and corner nodes

CTRL-click will insert corner nodes instead of normal nodes

  • click ... CTRL-click .... CTRL-click ... click

6.4 Creating a shape with straight lines, corner nodes and curves

By holding down the CTRL key, you can create corner nodes, i.e. produce new curves that start off in a different direction that the prior curve. A corner node (unlike the normal) does not sit in the middle of a curve.

  • click ... click CTRL-mouse-down+drag .... CTRL-mouse-down+drag ...
Creating corner nodes with curves

6.5 Creating straight nodes

  • To create a normal node with straight sides: Hold down the SHIFT key
  • To create a corner node with a straight side: Hold down both CTRL + SHIFT keys. Then for the next node you should release the SHIFT key. If you don't you can't drag out a curve...

Anyhow if this too much for starters, you always can just focus on normal (on-curve) vs. corner nodes, insert either straight lines or curves by dragging and then adjust/change some node types and curves/lines later. In other words, just go click, click, click and fix the result later and that includes changing node types.

7 Other shape modification techniques

7.1 Modifying built-in closed-shapes

In order to apply the various node and curve transformations, you first must convert the object to curves.

Converting a built-in closed shape to curves

Then, apply the recipes explained above, i.e. move nodes, change node types, delete nodes, add nodes, insert nodes and change curves.

7.2 Cutting shapes

Sometimes you wish to cut vectors apart. Typically you would like to change colors in various parts.

Splitting vectors procedure:

  • Click on Split vectors in the Reshape panel
  • Then draw a polyline: click, click, click ....
  • Then right-click -> Accept

You now will have two objects instead of one, and you can apply for instance a different fill color.

Split a vector (shape in this case)

7.3 Remove holes

The remove holes button in the Reshape panel allows to remove holes in a vector shape.

Removing holes

Warning: This will remove all holes, i.e. be careful when you apply this to larger areas that you created when vectorizing a bitmap for example!

8 Constructive solid geometry (CSG)

“Constructive solid geometry (CSG) is a technique used in solid modeling. Constructive solid geometry allows a modeler to create a complex surface or object by using Boolean operators to combine objects. Often CSG presents a model or surface that appears visually complex, but is actually little more than cleverly combined or decombined objects.” (wikipedia, March 2011)

This technique is quite popular in Computer-aided design and manufacturing. E.g. we used it through the OpenScad program in order to create 3D duplo-compatible bricks.

CSG is available through the Combine vectors panel

Basic procedure:

  • Select at least two vector objects objects (hold down the CTRL key and click)
  • Click on Combine vectors
  • Apply an operator.

Additional examples are discussed in tutorials like Stitch Era - digitizing complex bitmap images.

8.1 Subtraction example

You could draw a nice moon with the Bezier tool, but I find it easier to draw two overlapping circles and then subtract the second one from the first one ...

Combine vectors (CSG) - Addition

8.2 Addition example

The following example shows how to create a dumbbell for working out a bit after sitting down a few days learning Stitch Era.

  • Create a circle. Make sure that it is round using the layout tool.
  • copy the circle and move it down
  • Draw a rectangle with the Closed Shapes' tool and align it somewhat
  • Select the Layout tab and in the Align tab -> To Object, select Align horizontal centered
  • Select the three objects, e.g. by dragging the mouse
  • In the Combine vectors panel, select Addition
Combine vectors (CSG) - Addition

8.3 Intersection, rotation, simplify example

The following shows how to create flower petals from circles.

  • Create a circle
  • Duplicate the circle using the Matrix repetitions tool in the Layout Panel. Notice that use negative distances of -5mm in order to have them overlap.
Matrix repetition
  • Then, move the circles in place. I also killed the circle in the middle.
  • Select two circles and select Intersection in the combine vectors panel and repeat
Combine vectors (CSG) - Intersection
  • Adjust a bit. Use CTRL-arrows to move tiny bits and use CTRL-mouse to rotate a corner
  • Then select the remaining four petals and group with the right-click context menu (the latter is not needed really)
  • Make a copy, e.g. click on "duplicate" in the Layout tool
  • Move the copy over the the original
  • Rotate the copy as shown in the figure below (hold down the CTRL key and grab an angle)
Vector rotation
  • Select all and ungroup both groups (the one on top and the one underneath) with the right-click context menu
  • Adjust according to your needs (not shown here). You also can remove the borders ....
  • Add a little circle in the center.
  • You finally now could select all these petals and Simplify using again the Combine Vectors tool. Depends on whether you want the petals on top to be stitched over the ones underneath.

Now autodigitize:

  • Select all, the Convert->Art to Stitch Intelligent
  • In the Image to Sections tool, select Stitch Settings and set Maximum ZZ width to 3 .... else your petals will have both ZigZags and patters. You also can fix that later of course.
Simple flower made with CSG techniques

The fill patterns are not glorious, but working on these requires some extra work including some work with direction lines I think.

Morale: Sometimes using clever combination techniques makes life easier than drawing. All depends on your drawing skills. Personally I don't have much ....