Tutorial 16, Part A – Drawing Hair Using Live Path Effects

This tutorial comes in two parts. In this part, Tutorial 16, Part A, we will focus on the Stitch Sub-Paths Live Path Effect to draw hair. We will use the Envelope Deformation and Lattice Deformation Live Path Effects to refine the overall shapes of areas of hair and create the smooth flow of hair that is trained into a ponytail.

Tutorial 16, Part B, will introduce Sub-Path Interpolation for more flow effects.

You’ll learn how to do the following techniques:

• draw curves that connect two boundary curves.
• refine the shape of a multi-curve object using envelope deformation and lattice deformation tools.
• Use transparency and color blending to create a sense of hair depth.

In this tutorial, you will learn how to draw hair. You will be working with three Live Path Effects. Stitching Sub-paths is a live-path function with which you draw a starting line or curve, and an ending line or curve. These two boundaries are called sub-paths and help you define where a group of cross-lines start and where they end — you are graphically “stitching” the two sub-paths together.

A second and related live-path function is the sub-path interpolation live path effect. Instead of stitching two sub-paths together, you draw two lines or curves that make the sides of an area that you will fill with parallel or sub-parallel curves that change in shape from one sub-path on one side to the other path on the other side of the space to be filled. We will cover sub-path interpolation in the second part of this tutorial.

For more information about Live Path Effects, go to Help > Inkscape Manual > 8. Live Path Effects (LPEs), and click on Stitch Sub-Paths or Interpolate Sub-Paths.

1. Start Inkscape.

2. Download art file Tutorial16A_end.svg and store it in a convenient location.

3. File > Open file Tutorial16A_end.svg. This file displays a completed illustration of a young woman with a ponytail, facing away from the viewer.

   If you like, choose View > Zoom > Zoom Out to reduce the view of the finished artwork, adjust the window size, and leave it on your screen as you work. (Use the Select tool () to select and move the artwork where you want it in the window.) If you don’t want to leave the image open, choose File > Close.

Resource: For an illustration of the finished artwork in this tutorial, see the top of this page.

4. Download the art file Tutorial16A_start.svg and store it in a convenient location.

   

5. Choose File > Save As… and save the file as Ponytail.svg in a convenient location. This file will be your work file.

The art file contains the image of a young woman facing away from the camera. The image is on two layers: the bottom layer, which is locked, contains the woman as a mannequin figure; the second layer contains hair and right ear.

The hair is divided into separate areas. Each area contains hair whose flow has its own starting and ending points, degree of curvature, color and gradient shading. Each area has its own place in the overall image stack to create a sense of hair design as might be done in a salon.

The woman’s ear is its own grouped object so that it can be placed between two bodies of hair to enhance the sense of a 3-D presentation.

The task of this tutorial is to create overlays that you will place ontop of the areas of hair to create the look of strands of trained hair that follow the curvature of each area. The coloration of underlying areas and overlying hair filaments will be different to give the appearance of darker hair underneath that is not reached by the light, and lighter-colored, variegated hair that is reflecting light. The combination colors and styles of coloration produce subtle depth.

The Stitch Sub-Paths Live Path Effect is a great tool for “stringing together ” a starting and an ending boundary path, here called sub-paths. This section shows you how to analyze the underlying geometry that can guide you in determining how hair should flow and then in drawing it.

1. Select the top area of hair with the Select tool ().

   

2. Choose Edit > Duplicate to duplicate the area and then drag the duplicated area to a side where you can work on it without the distraction of adjacent hair areas.

   

3. The hair in this top area ideally appear as if it is coming from over the top edge and down into the lower, narrower part of the area that is constricted before it enters the ponytail. The figure below provides an idea template of how hair filaments might flow from top to bottom.

   You will create a “current” of hair that flows from over the top of the area into the narrow lower portion at the bottom using the Stitch Sub-Paths Live Path Effect.

   

4. Using the Pen tool (), draw two paths (sub-paths), one that follows the top curvature of the hair area and ends at a point just above the length of “straight” curve above the bottom, and the other following the curve that defines the bottom of the area.

   

5. Inkscape now “sees” the two sub-paths as two separate objects. Stitch Sub-Paths needs to see them as one path in order for it to work. The Path Combine function merges them into one item.

   First, group-select the two sub-paths using <Shift>-click. Each sub-path is enclosed in its own bounding box.

   

6. Choose Path > Combine. The sub-paths are now enclosed in one large common bounding box and Inkscape now “sees” the two sub-paths as one compound sub-path.

   

7. With the sub-paths still selected, choose Path > Path Effects…. The Path Effects dialog box appears.

   

8. Click on the Add path effect plus sign icon (). The Live Path Effects Selector appears.

   Scroll to the bottom of the Live Path Effects Selector until the Stitch Sub-Paths Live Path Effect appears.

   

9. Click on the Stitch Sub-Paths icon.

10. The Stitch Sub-Paths dialog box appears. The Number of paths might be different from that in the figure below, but that is not a problem. The lines, however, might have a different stroke color. In the figure, we chose a stroke color of yellow and a stroke width of 3 px, using the Fill and Stroke…, Stroke paint and Stroke style dialog boxes. The lines are easily visible and allow for easy modification. You will change the color of the lines to a more “hair-like” color shortly. Note that you can have both the Fill and Stroke and Path Effects dialogs active at the same time.

    

11. Change the Number of paths from 5 to 120.

    

12. Using the Fill and Stroke… Stroke style dialog box, change the hair stroke Width to 1.000 px. You now have a better idea of how to morph the hair pattern into what actually looks like hair.

    

    The shadowy wavy patterns in the hair are calle Moiré patterns. They are frequently visible in folds of cloth, or strands of hair that overlay each other, creating eye-catching, and yet attractive, interference patterns, such as waves and rays that radiate in or out in unpredictable directions.



13. The right side of the hair needs to be reshaped to match with the right side of the underlying area. Hair does not usually flow in a purely linear way – it usually has a degree of curvature in its flow. You will create a curved flow pattern using the Envelope Deformation Live Path Effect.

    Make the Path Effects dialog active and click on the Add path effect plus sign icon (). The Live Path Effects Selector appears.

    

14. Click on the Envelope Deformation icon. The Envelope Deformation dialog box appears.

    

15. The right side of the stitching line object needs the most adjustment of the four sides. You can accomplish this using the Edit on-canvas tool for the Right bend path (). Note that the icons for the four bend path tools look exactly like the Node tool in the toolbox.

    Click on the Right bend path tool icon.

    

16. The Right bend path tool is activated. A solid blue bounding box envelope surrounds the hair area in addition to the Select tool dashed bounding box. The right side of the deformation envelope is highlighted in red, informing you that it is the active side, awaiting your attention.

    

17. Place the cursor over the right side of the deformation rectangle. The cursor changes from the Node cursor to a hand cursor, indicating that it is hovering over an object that it can manipulate.

    

18. Click on the line and drag it to the lower right. Watch the rightmost stitch lines as you drag so that you can match the curvature of the lines with the curvature of the underlying shape.

    Use <Ctrl>-Z to undo any action that you consider a mistake and redo. You also have the option of fine tuning your work later. Any adjustments that you make now are not set in stone.

    

19. Now the bottom curve needs adjustment. Click on the Edit on-canvas tool for the Bottom bend path (). The bottom bend path is highlighted in red, indicating that it is ready for manipulation.

    

20. Click on the left-hand node of the bottom path bend line to activate it and drag it a little down to the left. Notice how quickly the bottom part of the stitched paths object responds to small adjustment moves. Stop when you get a good shape match.

    

21. The left side of the stitched path object can use some micro-adjustment in the overlap.

    Click on the Left bend path tool icon and drag the left-hand node to the left a very little bit.

    

22. The right side of the stitched sub-path object can use a little more micro-adjustment in the overlap.

    Click on the Right bend path tool icon and pull the right bend path to the right and down a very little bit to make the rightmost lines cover the very little bit of exposed dark brown area.

    

23. You will now change the color of the hair from yellow to a dark reddish brown.

    In the Fill and Stroke dialog box, click on the Stroke paint tab, and enter the hexadecimal code for a dark reddish brown stroke color 3c2316ff in the RGBA text box.

    

24. The strands of hair are almost invisible against the darker reddish brown of the background. You will make the hair glisten by giving it a gradient highlight.

    Click on the Linear gradient icon () in the Stroke paint dialog box and then click on the Create and edit gradients tool icon () in the toolbox.

    

25. Click on the circular node on the gradient tool line and drag it to the upper area of the hair area shape. Click on the square node on the opposite end of the gradient tool line and drag it to the lower area of the hair area shape.

26. Double-click in the middle of the gradient line to add a gradient stop at that point. Its shape is a small diamond, colored blue because it is active. That midpoint gradient stop will control a band of lighter reddish brown which will be the highlight.

    With the midpoint stop still selected (colored blue), click on the HSL tab (Hue, Saturation, Lightness), and enter the numbers shown in the figure below. Move the two nodes on the gradient tool line to obtain a highlight that looks reasonable to you.

    

27. Some stitch lines poke out at the top and extend out on the right.

    Micro-adjust them so that they won’t stick out by clicking on the Select tool () and moving the sizing handles on the object’s bounding box to align the upper and lower images just right.

    

28. Marquee-select the hair shape to group-select both the underlying dark reddish brown hair area and the stitch-path object. Click the Group selected objects icon () to group the two objects.



29. You will now replace the original flat colored hair area with the new area with the stitched-sub-path overlay.

    Move the grouped hair area to near the model’s head.

    

30. If the Snap Controls Bar isn’t active, choose View > Show/Hide, and check the Snap Controls Bar checkbox. Click on Enable snapping (%) (), Snap other points (centers, guide origins, gradient handles, etc.) (), and Snap centers of objects (). (The Snap centers of objects icon has been darkened to make details more visible.)

    With the Select tool (), drag the finished area of hair so that it lies directly ontop of the original flat red-brown area. Because the Snap centers of objects tool is activated, you will see a pop-up tooltip letting you know when the center of the hair is directly ontop of the flat color area as shown below.

    

31. With the hair object still selected, click on the Lower selection one step icon () until it disappears underneath the flat color area and the knot above the ponytail. It is now two levels down in the image stack.

    

32. Click away from the artwork to deselect it and then click on the flat reddish brown area. Because the flat colored area lies ontop of the hair object, it is the object that is preferentially selected.

    Move the flat color area off the artwork to reveal the hair object underneath.

    

33. With the flat color object still selected, press the <Del> or <Delete> key to delete it.

34. 

35. You have just drawn hair with its own color, highlighting, flow, and placement in the image stack that makes up the young woman’s head.

    Choose File > Save to save your artwork.

We explore working with stitching sub-paths in combination with color blending and using the Lattice Deformation 2 Live Path Effect to create a second area of trained hair so that it exhibits a natural look to a viewer.

1. Select the right-side area of hair with the Select tool ().

   

2. Duplicate the area by pressing <Ctrl>-D and move the duplicate to the side of the figure.

   

3. Using the Pen tool (), draw two paths (sub-paths): one following the top curvature of the hair area and the other following the curve at the lower left corner of the shape. Draw both paths in the same direction, that is, from left to right, or from right to left.

   

4. Group-select the two sub-paths using <Shift>-click. Each sub-path is enclosed in its own bounding box.

   

5. Choose Path > Combine. The sub-paths are now enclosed in one large common bounding box and are now merged into one compound path.

   

6. With the sub-paths still selected, choose Path > Path Effects…. The Path Effects dialog box appears.

   

7. Click on the Add path effect plus sign icon (). The Live Path Effects Selector appears.

   Scroll to the bottom of the Live Path Effects Selector until the Stitch Sub-Paths Live Path Effect appears.

   

8. Click on the Stitch Sub-Paths icon.

9. The Stitch Sub-Paths dialog box appears. The Number of paths is 5, which is the default number for newly created path objects like this, but that is not a problem. The lines, however, might have a different stroke color. In the figure, we chose a stroke color of yellow and a stroke width of 4 px, using the Fill and Stroke…, Stroke paint and Stroke style dialog boxes. The lines are easily visible and allow for easy modification. You will change the color of the lines to a more “hair-like” color shortly.

   

10. Change the Number of paths from 5 to 80. The stitch lines are thick enough (4 pixels width) that they form a swath of yellow.

    

11. Make the Fill and Stroke dialog box active, click on the Stroke style tab, and change the stroke Width to 1.500 px. You can start to see individual lines.

    



12. Inkscape allows you to randomly change the spacing between adjacent stitch lines. You will apply this function to create uneven spacing between lines.

    Make the Stitch Sub-Paths dialog box active. Enter 7 into the Start spacing variance and End spacing variance text boxes. Then click on the Random number generator icon () for each option and continue clicking until you get a spacing style that you like.

    Note: each time you click a Random number generator icon, Inkscape creates a new sequence of random numbers that you can use in turn in creating unevenness in how far stitch paths are positioned from each other. This feature is particularly useful in producing the trained, and yet subtley uneven spacing between hair strands in this project. Larger values for a random number generator produce larger variations in random values. They can result in larger spacings between adjacent lines. A value of 0 creates regular spacing, that is, the Random number generator is turned off.

    Experiment with different values for a random number generator and see what you get. The more you use it, the more you develop your intuition for how to use it.

    

13. Click on the Add path effect plus sign icon (). The Live Path Effects Selector appears.

    

14. Click on the Lattice Deformation 2 icon. The deformation lattice (or deformation grid) appears encompassing the stitch line object. Note that it does not totally include the underlying swath of color, indicating that only the yellow lines will be affected.

    In the Path Effects dialog box, Lattice Deformation 2 has been added to the path effects listing and is highlighted, indicating that it is the currently active path effect, awaiting your commands.

    

15. There are movable nodes where lattice lines cross. Click on a node to select it and then drag it around to get the feel for how they affect the yellow lines.

    When you feel comfortable moving them around (even somewhat comfortable is very okay), experiment with moving them so that allow the yellow lines bend conformably with the bounding left and right edges of the underlying shape. If you don’t like a result, then copy the node geometry in the figure below. Fine-tune their positions as you see fit. The more you play with the lattice, the more confident you will feel using this tool and the more easily you will be able to manipulation shapes into how you envision them.

    

16. The hair color needs to be changed from yellow to a reddish brown color that matches the underlying color. It should be lighter in color because it is being illuminated by a light source off-camera. Using the Screen color blend will heighten the effect of a diffuse light source and also give the impression that there is underlying hair receiving less illumination.

    Make the Fill and Stroke dialog box active, click on the Stroke paint tab, and type 7e1b1bff into the RGBA text field. Click on the down arrow at the right of the Blend mode selection box and choose Screen in the color blend mode list. Set the value of Opacity (%) to 70.0.

    

17. Marquee-select the artwork (you need to select both the overlying hair object and the underlying hair shape) and press <Ctrl>-G to group them.

    Move the grouped hair object onto the figure’s head so that it completely covers the original area of hair. You can optionally delete the original area by lowering the grouped object by one level, deselecting the original area, and then selecting the original one simply by clicking on it (it is now at the top of the image stack). You can then delete it by pressing the <Del> or <Delete> key.

    

18. If the grouped hair object lies above the knot at the top of the ponytail, then select the object and click on the Lower selection one step icon () until it disappears underneath the knot.

    

19. Deselect the grouped hair object by clicking anywhere off the artwork. It’s possible that the grouped hair object is not exactly in place on the figure’s head, as illustrated below. If this is the case, then it is very easy to fix.

    

20. Zoom in with the Zoom tool or increase the magnification using the magnification indicator at the lower right corner of the work window until you can clearly see how large the discrepancy in placement is.

    Select the grouped hair object with the Select tool () and move it (up, down, right, and/or left) until it’s top curve matches that of the top area of hair.

    

21. When you are satisfied with now things look, deselect the grouped hair object.

22. The top area of hair does not have a random look to the placement of hair filaments. It is unrealistic to see such mathematical precision in combed hair. There is always a little bit of unevenness.

    Select the top area of hair.

    Make the Path Effects dialog box active.

    Click on the Stitch Sub-Paths Live Path Effect.

    

23. Set both Start spacing variance and End spacing variance to 4.00.

    Click either or both associated Random number generator icons () and continue clicking until you get a spacing style that you like.

    

24. When you are satisfied with what you see, deselect the artwork by pressing <Esc>.

    

25. Save your work with File > Save.

This section can act as a review of the previous two sections: you will be using the same tools and techniques as you draw hair that makes up the knot above the ponytail. Instead of using color blending, you will use the Opacity tool to use transparency as a way to shade the upper layer of hair differently from the color texture underneath.

1. Select the knot of hair above the ponytail with the Select tool ().

   

2. Duplicate the area by pressing <Ctrl>-D and move the duplicate to the side of the figure.

   

3. Using the Pen tool (), draw two paths (sub-paths): one following the left side of the hair area and the other following the right side of the shape. Draw both paths in the same direction, that is, from up to down, or from down to up.

   

4. Group-select the two sub-paths using <Shift>-click. Each sub-path is enclosed in its own bounding box.

   

5. Choose Path > Combine. The sub-paths are now enclosed in one large common bounding box and are now merged into one compound path.

   

6. With the sub-paths still selected, choose Path > Path Effects…. The Path Effects dialog box appears.

   



7. Click on the Add path effect plus sign icon (). The Live Path Effects Selector appears.

   Scroll to the bottom of the Live Path Effects Selector until the Stitch Sub-Paths Live Path Effect appears.

   

8. Click on the Stitch Sub-Paths icon.

9. The Stitch Sub-Paths dialog box appears. The Number of paths is 5, the default number for new path objects as you saw in the previous section. The lines, however, might have a different stroke color. In the figure, we chose a stroke color of yellow and a stroke width of 4 px, using the Fill and Stroke…, Stroke paint and Stroke style dialog boxes. The lines are easily visible and allow for easy modification. You will change the color of the lines to a more “hair-like” color shortly.

   

10. Change the Number of paths from 5 to 35. The stitch lines are so thick (3 pixels width) that they form a swath of yellow with little spacing between adjacent lines.

    

11. Make the Fill and Stroke dialog box active, click on the Stroke style tab, and change the stroke Width to 1.500 px. You can now see individual lines.

    

12. Click on the Add path effect plus sign icon (). The Live Path Effects Selector appears.

    

13. Click on the Lattice Deformation 2 icon. The deformation lattice (or deformation grid) appears encompassing the stitch line object. Note that it does not totally include the underlying swath of color, indicating that only the yellow lines will be affected.

    In the Path Effects dialog box, Lattice Deformation 2 has been added to the path effects listing and is highlighted, indicating that it is the currently active path effect, awaiting your commands.

    

14. Move the nodes around in the lattice grid until the stitch lines lie conformably with the upper right and lower left edges of the underlying shape. If you find that you’re having difficulty getting the effect you want, then copy the node placement in the figure below. The grid won’t look like an organized lattice anymore, but the stitch lines flow in agreement with the underlying shape edges, which is what you want.

    

15. You will now make the spacing between stitch lines uneven to simulate real hair.

    Make the Stitch Sub-Paths dialog box active. Enter 3 into the Start spacing variance and End spacing variance text boxes. Then click on the Random number generator icon () for each option and continue clicking until you get a spacing style that you like.

    

16. The hair color needs to be changed from yellow to a reddish brown color that matches the underlying color, but darker. It should be darker in color because it is receiving less illumination than the right side of the figure’s hair and head.

    Make the Fill and Stroke dialog box active, click on the Stroke paint tab, and type 271207ff as the hexadecimal color value into the RGBA text field if it doesn’t have that value already. If Normal is not the current color blend mode, then click on the down arrow at the right of the Blend mode selection box and choose Normal in the list. Set the value of Opacity (%) to 70.0.

    

17. Marquee-select the artwork (you need to select both the overlying hair object and the underlying hair shape), and press <Ctrl>-G to group them.

    Move the grouped hair object onto the figure’s head so that it completely covers the original knot shape. You can optionally delete the original knot by lowering the grouped object by one level, deselecting the original knot, and then selecting the original one simply by clicking on it (it is now at the top of the image stack). You can then delete it by pressing the <Del> or <Delete> key.

    

18. Zoom in with the Zoom tool or increase the magnification using the magnification indicator at the lower right corner of the work window so that you can clearly see whether there is any discrepancy in placement.

    Select the knot object with the Select tool () and move it (up, down, right, and/or left) until you are satisfied with its placement.

    

19. When you are satisfied with how things look, deselect the grouped hair object.

    

20. File > Save to save your artwork. File > Quit to exit Inkscape.

You have learned how to draw and texture hair using the Stitch Sub-Paths, Envelope Deformation, and Lattice Deformation Live Path Effects. Color blending and transparency refine your sense of how to create three-dimensionality using color to give subtle, and yet believable depth to your artwork. You will finish the artwork of this tutorial in Tutorial 16, Part B, where you will be introduced to the Sub-Path Interpolation Live Path Effect which can make filling certain shapes with lines easier than with Stitch Sub-Paths.

1. How are Stitch Sub-Paths, Envelope Deformation, and Lattice Deformation related as workflow tools as you create hair?
2. How are Envelope Deformation and Lattice Deformation different from each other?

1. The Stitch Sub-Paths, Envelope Deformation, and Lattice Deformation tools are related in your workflow in that you first draw the hair using Stitch Sub-Paths. To make the hair strands curved, you need to modify their original straight lengths using either Envelope Deformation or Lattice Deformation. Envelope Deformation can be used for simple shapes and Lattice Deformation should be used for shapes having complex geometries.

2. Envelope Deformation affects the overall shape of an object using sides of a bounding box envelope. The top, left, right, and bottom sides are separable tools whereby you can change the shape of each side’s line segment and end nodes without affecting the other sides.

   Lattice Deformation works via a lattice grid whereby you can change the curvature and location of points both on the edges and inside a shape, producing complex modifications that Envelope Deformation can’t do.