I want to sell some T-shirts, so I'm experimenting with Inkscape to produce vector graphics for the designs. I once spray-painted a tee shirt with some Volkswagen logos on it. The results were extremely attractive. Now I want to reproduce that with vector graphics.
It's surprisingly difficult to make blotches. Although I couldn't get a spray paint effect, I finally got a wet paintbrush stroke to work. Continue reading for my method.
After a great deal of experimentation, I came up with a method that produces reasonable results. I'm recording it here for my reference and your edification. My original wet-paintbrush Inkscape file and a crippled, exported EPS version of the wet paintbrush stroke are available for download.
Big Wet Paintbrush Stroke
Create a 5px circle. Use Edit -> Clone -> Create Tiled Clones... with the following settings to make a splotchy rectangle:
- Symmetry: simple translation
- Shift: -40% X/column, Randomize 50% X and Y, Exponent 0.8 / row
- Scale: Randomize 50% X and Y
- Rows: 10
- Columns: 100
Keep hitting Create until you've got something that's almost full on the right and splotchy on the left, like the beginning of a wet paintbrush stroke.
Create a second splotchy rectangle using the same parameters and mirror it horizontally. It's going to be the end of the paintbrush stroke.
Put the two together. The center should be completely opaque, with splotchy ends.
Now the time consuming part: select the whole thing and use Edit -> Clone -> Unlink Clone (Alt+Shift+D). You might want to select just a few at a time; that prevents the computer from completely locking up.
Make sure all the circles are selected and use Path -> Object to Path (Shift+Ctrl+C), then Path -> Union (Ctrl++). Wait a long time for it to finish up. Simplify the curve with Path -> Simplify (Ctrl+L).
Finally, draw the path for the brush stroke. Select the brush, then the path, and select Effects -> Generate From Path -> Pattern Along Path. Repeat the images with Snake deformation. Play with the Space Between Copies until you find the one that creates a solid center with no banding; I used -60 for mine.
Pretty good, eh? ShirtCity didn't like it much; some of the features were smaller than 1.5mm, which they refuse to print. Oh well; I can always scale it up next time.