Rubens kindly recorded his vector process and provided an overview of the tools and techniques he used to create the illustration below.
Rubens’ illustration process
Sketching the art
With an idea in mind, I started by making several pencil sketches on paper.
After being satisfied with one of them, I scanned it, did a quick colourization with just three colours and included a few more bats.
In my own projects, I usually don’t worry about the colours at this stage. Some changes are also made to the artwork during the vectorization process.
In this initial phase, I used the Pen Tool to outline the entire drawing on a new layer—the original sketch is at a reduced opacity and locked to the bottom layer.
Then, still using the Pen Tool, I made the fills that will be joined to the strokes after being expanded. In this step, I used the Node Tool a lot to move points and strokes.
Other tools I used were Geometry, Contour, Corner, Artistic Text, Rectangle, Ellipse and one of my favourites, the Pressure Tool from the Stroke palette. With it, it is possible to modify the thickness of the line at different points, making the strokes more organic.
Once the line art is finished, it’s time to expand it. With the lines selected, I clicked on Expand Stroke in the Layer menu and made some spot adjustments with the Node Tool. I then converted the corners into rounded corners with the Corner Tool and fixed any issues that might compromise the quality of the art. Next, I selected all curves of the same colour using Select/Select Same/Fill Color and clicked Add to merge everything.
With the outlines and dark areas converted to curves, I added the colours. As this illustration will be silkscreen printed, I limited the colours to five, with the dark colour being the colour of the shirt.
My technique for creating the areas to be coloured was as follows: first, I duplicated the line art layer and made it un-visible. I then created a shape that covered the entire visible line art and moved it down.
Next, I selected the line art and shape, then applied Subtract in the Geometry menu. I then clicked Divide to separate the curve into several curves and deleted the excess curves.
I left the line art layer visible and then started applying the colours.
Ok, now the illustration is in colour, but it lacks that three-dimensional effect to make it more impressive. Taking care not to exceed the colour limit, I started applying the highlights and shadows using the Pen Tool and adjusted with the Node Tool.
This is a very simple process using just a few tools, but the result was very satisfying for me.
The final illustration
The final illustration on a t-shirt: