I spent a couple of hours working on a graphic of a dandelion the other weekend and I thought I would share how it was done.

The design is simple. Using Inkscape, I began by drawing the dandelion stalk using the Freehand Tool (using spiro for that nice curve) and coloured it with a slight gradient from pale green to dark green.

For the head I simply drew a circle and filled large number of very small star-shaped hand-drawn polygons. Drawing these by hand meant I was able to ensure a good placement. Initially I had drawn a series of star shapes and tried using tile clones to place them radially. This created a very geometric look so I decided to hand-draw for a more organic feel.

After filling the circle with stars a few were dragged across the canvas to create the “just blown” look. I then made the guide circle completely transparent. Leaving it there meant I could still check the placement of the stars by viewing the image in Outline Mode (View>Display Mode>Outline).

The star shapes were selected (Edit>Select All and while holding Shift, click on the stalk to deselect) and in the Fill & Stroke Dialogue I set the blur to around 3. The stars were copied and pasted in place and while the duplicate stars were still selected I set the blur back down to zero. This makes a sharp star shape with a blurred halo, creating a soft appearance without losing detail.

And that’s pretty much all there is to it. Opinions welcomed.

Now you have your development version of Inkscape running, let’s have a look at the Spiro option. Select the Freehand (Pencil) Tool. You’ll notice an addition to the toolbar:
Make sure the “Create Spiro Path” mode is selected as shown. This will correct your freehand lines to smooth curves which you can adjust using the Smoothing Slider. Currently this can only be set before drawing your line so some experimentation will probably be required to get the amount of smoothing right.
This image shows you how it works. The blue path shows the line I drew. The purple line shows the path with Spiro applied.

As with any path, you can edit each node and the Spiro path will adjust accordingly.

Shape

Spiro paths can be shaped. This shows each type of path; None, Triangle In, Triangle Out, Ellipse, From Clipboard.

None: This draws a simple line with no shaping which you can thicken or thin using the Stroke Style dialogue. There you can choose the cap or even add markers to your line. Change the colour using the Stroke Colour dialogue.

Triangle In & Triangle out: The line is thickened at one end. By default you can change its colour using the Fill Dialogue but you can also apply a stroke colour. If you do so the stroke is an outline of the triangle shape so thickening it will eventually cover over the fill colour rather than increase the size of the whole object.

From Clipboard: Use an existing path to shape your spiro path. In the example above I used a star shape and applied it to a curved line to create the deformed star shape. You must use a path for this trick to work. If you draw a shape you’ll need to convert it to a path first Path>Object to Path. The colour of your original shape will not be preserved.

How can you thicken a shaped Spiro path?
Try resizing a shaped Spiro path and you’ll soon see that proportionately remains the same, but what if you want a much thicker object than the one you drew? If you thicken the stroke you’ll find the lines are blunted and the fill colour becomes occluded by the stroke. The secret is to draw small and scale up. Here’s an example.

The two paths on the left show how scaling a medium sized path up slightly thickens the overall object.  The two paths on the right show how drawing a very small path allows much more noticeable thickening when the image is scaled up.

Notice how the stroke has scaled with the image? If you don’t like this effect you can decrease the stroke thickness through the Stroke Style Dialogue.

This is quite a dirty workaround to the problem and hopefully a better  solution will be incorporated into the final release.

When I first read about the new spiro feature on Andy Fitzsimon’s blog I thought it was so cool I had to have a go.

Spiro is a new feature in development for Inkscape which is an add-on to the Freehand Tool. It modifies your stroke path into spirals giving a very fluid look to curves and lines. Spiro isn’t the only new tool for the next version of Inkscape. There are new filter effects to play with so it really is well worth the hassle of trying development version.

Check out the download page for the most recent builds for your operating system. You’re likely to find the development version pretty unstable so don’t go deleting your copy of 0.46 just yet.

I use OS X 10.4 which currently has no up-to-date downloads available so I’ve had to compile it myself. If you’re in the same position, it’s not as hard as it looks. Read Inkscape’s page on compiling Inkscape on OS X. Make sure you have XTools installed (searching for it in finder will be enough). On my copy of 10.4 it was already installed. If it isn’t, you’ll find it on your installation CD.

I’m going to show you how to download and install this using MacPorts. If you want to use MacPorts for the download instead of installing everything manually, you’ll need a newer version of XTools. I found the correct version on Download.com as it’s no longer available on the Apple Developer Network for 10.4.

For this installation you’ll be using the program Terminal to work from the command line.

Tip: If you’re using the packaged version and get “command not found” when you try running the port command, see this work around. If you already have a .bash file, open it (nano .profile), copy the line inserted by macports and paste it into your .bash_profile and it should now work.

Assuming you got MacPorts up and running, copy and paste this into Terminal. Expect it to take a long time to run. You’ll be required to enter your system password.

sudo port install cairo +pdf boehmgc gtkmm intltool libxslt lcms popt poppler boost gnome-vfs \ libgnomeprintui automake autoconf subversion

Finally, to complete it, run this command:

svn co https://inkscape.svn.sourceforge.net/svnroot/inkscape/inkscape/trunk inkscape cd inkscape/packaging/macosx/./osx-build.sh a c b i -s p

Navigate to your new Inkscape directory and into the folder packaging/macosx/ and open the file named Inkscape to run it.

Next: Using Spiro paths.

In my absence I’ve been working on a design for something I’m going to have laser cut. Who wouldn’t love to have their very own laser cutting machine? I know I would but until then I’ll be sending my work off to a specialist company, so I’ll keep you posted on how that goes.

As part of the design I was working on I came up with this leaf design. I started out just sketching line drawings in Inkscape and quickly came up with something I liked. The only problem is that when laser cutting you need to provide outlines for the laser to follow - not solid blocks of colours or thick lines. I was able to get around this problem and come up with a new technique using the bucket fill tool. Here’s how…

I started with this leaf shape. It was a 5 sided polygon that I reshaped to look like a maple leaf. I’ve also drawn a jagged outline with the pencil tool. It’s coloured pink to show you how it’s constructed but the final image will be black and white.

The next stage was to draw on the veins. To to this use the pencil tool and click once at the starting point and once at the end point. This creates a straight line rather than trying to drag a straight line. Use the node editor to click on each line to bend it into the desired shape.

Draw in the smaller veins until you’ve filled in your leaf shape.

In this image I’ve coloured all the strokes white and I’ve changed the page colour so that the white outlines are visible.

If it wasn’t going for laser cutting I would stop at this point but since the laser needs a line to follow, if I supplied this as the outline I would end up with just a cutout leaf shape and none of the vein detail.

For that I’ll need to outline the lines!

The Bucket Fill Tool  is really handy for this. Set the fill to be “none” and the stroke to black. The stroke for this stage needs to be thinner than your white stroke areas so that you can have detail in the corners.

You can either apply the bucket fill to each of the void areas in turn or just click on your white outline area for an almost identical finish.

Finally set your page colour back to white to get the full effect.

Following on from yesterday’s faceted diamond shape, I’m going to show you a few ways to tidy up the edges without the need for time consuming node editing.

Here’s our shape from yesterday. In order to make it look more diamond-like we’ll need to get rid of those sharp edges and form it into a more uniform shape.
If you look at the shape, you could fit the areas where two or more colours overlap into a 12 sided shape so make a polygon and fit it into the shape. I’ve outlined it here to show you but what you need is a white dodecahedron (I’ve been waiting to write that!) filled white at around 30% with no outline. It should fill most of the diamond shape.

The 12-sided polygon will be used to shape the diamond.

There are two ways of doing this; clips and masks.

Clip
Move your 12-sided shape on top of the diamond. For clipping it doesn’t matter what colour your top shape is as this won’t show when the clip is applied. Select the diamond shape and your 12-sided shape and go to Object>Clip>Set. Everything under your 12-sided shape will be showing and anything outside of it is hidden. You can undo it by going to Object>Clip>Release. The image below shows the diamond shape with the polygon positioned on top, then after clipping is applied.

Mask
Mask works in a similar way to clipping except that it retains some of the properties of the mask object. This time the white semi-opaque colour of the 12-sided shape will be applied as well as the clipping. This will give the coloured object the transparency of the mask above. Here’s how it looks now:

That’s possibly too transparent but you get the idea. Release the mask and adjust the transparency on the mask object and reapply the mask if you’re unhappy with it.

Note: If you want to apply a gradient as a mask use a black>white gradient.

If you copy and paste in place the mask object on top of a clipped object you can give the diamond a more glassy look:

Play around with it until you end up with something you like. All the files for this are available from yesterday’s tutorial including the various clipped and masked objects with explanations.

10 days and no posting. I spent most of last week in Ireland and I couldn’t bring myself to look at a computer. It’s nice to have a break sometimes.
Anyway, I’m back with my semi-regular 3 posts a week.

Today I’m going to show you a technique for making faceted shapes in Inkscape using simple geometry.

Start by making a six-sided polygon with equal width and height. Set the transparency to 33%. Copy and Paste another 3 polygons and colour them red, green, blue and white. Arrange the red green and blue hexagons so that they each have a side touching another colour and place the white hexagon on top spanning the red, green and blue shapes.

It should look similar to this (left).

Group (select them and press Ctrl + G or go to Object>Group) the 4 hexagons together and make 1 copy. Rotate one of the groups by 180° (Object>Transform…) and arrange them so that the white hexagons align. It’s starting to look kind of faceted but it lacks detail (right). Let’s make another set of hexagons to add dimension.

Repeat the steps above but this time use only the red, green and blue hexagons. Make 2 groups of 3 hexagons and rotate one of them by 180° as before. You’ll have something like this on the right.

Each group forms a larger hexagon. Rotate one of these by 30° so that the two shapes will intersect each other rather than line up one on top of the other. Combine the two hexagon groups so that the set with the white hexagon will be on top. The end result is a faceted diamond shape… well sort of.

Tomorrow I’ll show you a couple of ways you can tidy this shape up, make it look more like a diamond and trim off the rough edges.

Download the SVG but read the license first please.

How often do you opt for a solid or gradient fill for your Inkscape drawings? Have you ever used the Pattern Fill?

Here’s an example of a star shape filled solid pink next to one filled “Ermine”.

This is as simple as setting any other fill.

You can change the opacity and blur filters on Pattern Fill but not the colour… at least not without cheating a bit!

This method is by no means predictable but can create interesting effects. Select your patterned object and go to Effects>Color and try out some of the colour effects. It seems that not all effects work with all patterns. Polka Dots, Stripes and Checkerboard seem to work best with Randomize and RGB Barrel colour effects.

You can also change the scale and orientation of your pattern. This can be buggy so save your work first.

Use the Node Select Tool to select your patterned fill. You’ll notice to the top left an ‘x’ shape with circular and square handles. To increase the size of the pattern just move the square handle away from the ‘x’ and to rotate move the circular handle around the x.

Since most of the patterns are semi-transparent you can layer them up (right).
You don’t have to use the presets to fill your objects - you can make patterns out of objects!

Create the objects you want to use as your pattern as well as an object you want to fill with pattern. Here I’m using a square for the background with a shape on top. Group your pattern objects (Ctrl +G) and then go to Object>Pattern>Objects to Pattern.

To fill your other object with your new pattern just click on it, select pattern fill and choose your new pattern. It will probably have a name like Pattern3806.

I’m unsure why the edges are visible. I tried using a thick outline for the square shape but it was unsuccessful. If you have any tips for that drop me a comment below.

Finally if you want to fill a shape with a bitmap it’s just as simple. Go to File>Import and select your bitmap image. Now as before, select the bitmap and go to Object>Pattern>Objects to Pattern. You now have a new pattern to fill with.

Any comments/questions/suggestions? Let me know!

Back when I first started using Inkscape some of the things I found difficult to make work were the boolean operations in the path menu; things like Union, Difference, Intersect etc. To me the results were difficult to predict and some of the operations seemed pretty similar.

In this article I aim to explain these tools and show you how to get predictable controlled results.

Union
The first thing you need to do is select the two (or more) objects you want to combine. Let’s begin with the Union option. Select your objects and go to Path>Union (Ctrl++). This will combine the shapes, with the top object taking on the colour and opacity of the lower.

Before & After

You can see the paths have been combined. This can be really useful when making complex shapes. You can save yourself a lot of node editing if you can construct your shape in this way.

Difference
Difference works in much the same way except the top object is removed from the bottom shape.

Intersection
This excludes everything except the areas where the two shapes overlap.

Exclusion
Exclusion is probably my favourite of the boolean operations. Everything but the overlapped area remains and as before the top shape takes on the properties of the bottom shape.

Division
Division only works if you have outlines, otherwise the result won’t be visible. It colours the top object but each retains its own path; so the edge of the star shape can be selected separately from the square.

Cut Path
This operation breaks the path where the two objects intersect allowing you to remove the section.

So there you have it. I hope this clears things up if you have been confused by these path options. I’ll be covering the rest of the path menu in the next few weeks.

It’s Friday, I’m feeling a bit lazy so today I’m just going to point you in the direction of some interesting Inkscape tutorials that you might want to take a look at over the weekend.

I have some major bug fixing to do on one of my other sites but will prepare some shiny new tutorials for next week!

Illustrating Tomato is a nice tutorial from kalaalog.com. It’s not so much the tomatoes I find interesting, but the technique of first hand drawing them and then making shapes around the drawing. Gives a nice hand-drawn finish.

Inkscape Docs Interpolate Tutorial - if you haven’t got this far through the Inkscape documentation take a look at this well-written tutorial on interpolate. It’s a very cool tool in inkscape for morphing from one shape or colour to another.

Gradients to Path is such a simple yet brilliant idea. A really easy way to make a gradient or abstract shape using markers on a line.

3D Text by Nicu is an easy to follow tutorial on getting an embossed look on text using the blur filter. Could work well with non-text objects too.

That should keep you going until next week when I’ll be concentrating on some fairly heavy going GIMP tutorials on photo restoration. Have a great weekend!

Do you write web comics? To take some of the effort out of it and save time, here’s an easy way to make speech bubbles that you can use each time you write a new comic.

The Rounded Speech Bubble
Start with an ellipse. In this example I’ve given it a grey outline and blurred it slightly. Click on the shape and go to Path>Object to Path.

Here we’ll add the point to the speech bubble to the bottom-left of the ellipse, so shift-click using the Edit Paths Tool on the bottom and left nodes to select them and Add a Node between them. Now select just the new node and change it to be a Corner Node

Pull the new node in the direction you want for your speech bubble. It’s now taking on a speech-bubble-like shape but it doesn’t look right yet. For that you’ll need to edit your new nodes Bezier handles to form a sharper point. Still using the Edit Paths Tool move the node’s handles so that they are at about a 45° angle and pointing back towards your original ellipse shape.

You can also lengthen the handles on your corner node to make the point thinner. All that remains is to create a text area inside your bubble and fill it with some sample text of your choice. You can flip your bubble horizontally and/or vertically to change the direction and to move the point, simply select the corner node with the Edit Paths Tool and drag it in the direction of your character.

It’s really easy to repeat the process using a square. You’ll probably want to round the corners. You can do this by changing the Rx and Ry values for your square or rectangle:

Check out this post on Playing with Polygons for details on how to make star bursts and other shapes.

Tip: To make a thought bubble start with a softened star burst shape:

Now resize it so that it’s wider than it is long. Add a few circle shapes et voila!

You can download the files for these images and play with them yourself. Check out the License Agreement first.