Harnessing Randomization in Adobe Illustrator
This is primarily a tutorial for how to create the above image using color and rotation randomization in Adobe Illustrator. However, it’s also a look at how randomizing various properties of groups of objects in Illustrator can be a great way to generate interesting results quickly. The above image is the last of eight designs in my Randomization Poster Series, which was made using nothing but standard Illustrator shapes, and randomization:
Sticking to Generative Hut’s black and white style, this tutorial is only focused on the last poster in the series. A basic knowledge of Adobe Illustrator would help to follow along.
The overall grid of squares we’ll be working with is 13x10 squares, with each square being 1.5 inches wide. So the art board setup will be 19.5 inches wide by 15 inches high.
Now we have to make a square of 1.5” x 1.5” as our starting point.
In the top-left corner of that square, make another square with dimensions of 0.15”x0.15. One tenth as large. Fill the larger square with black, the smaller square with white, and remove any stroke from both squares.
Creating the Blend
Next we’re going to set up a blend. In the menu, go to Object > Blend > Blend Options, and set ‘Spacing’ to be ‘Specified Steps’, and set the number of steps to 70. Feel free to play around with this value.
Now select both squares and make the blend with Object > Blend > Make Blend. Your two squares should now have 70 intermediate squares between them, transitioning from black to white.
We need each square to be it’s own select-able object, so we have to expand the blend. Do this with Object > Expand.
Your blend should now be expanded, with each square within it’s own object. Make sure the blend is ungrouped, and each square can be individually selected.
Creating the Gradients
The next step is to create several linear, metallic gradients that you will randomly apply to all of the squares in the blend. This can be kind of time consuming, so you might want to grab a free, pre-made collection of metal gradients such as the one made by TrabzonSport on DeviantArt. I've picked 6 silver gradients out of that collection, and placed them above the art board.
Applying the Gradients
Once you’ve created the gradients, it’s time to start randomizing. Basically, we want to randomly pick and apply one of these metal gradients as the fill color for each square. I’m using a plugin I developed called Randomill that this next step much easier, but it’s not absolutely required.
To do this with Randomill, follow these steps:
In the Randomill plugin panel, toggle on Fill Color.
Click the Color Set tab.
Select all the gradients you’ve made, and import them into the Randomill Color Set using the Add Fills button.
Select the squares in the blend and click the Randomize button.
Note: If you want to use a free script to apply the colors instead, this video has a good tutorial on how to do that.
Rotating the Gradients
Now we have a good distribution of these gradients, but they’re only visible on half of each square. We need to rotate each gradient 45 degrees. Randomill’s rotate feature can handle this as well.
Turn off Fill Color randomization
Turn on Rotation Randomization
Set the Minimum and Maximum fields to 45 degrees
In the Advanced Options, uncheck all fields except for Gradient Fills.
Note: If you’re not using Randomill, you may have to rotate these gradients by hand. I’m not aware of an existing script that can do this. I tried first rotating the gradients 45 degrees, and then randomly applying them as fill color but that didn’t work. I also tried rotating the squares 45 degrees, and then applying the gradients, but that didn’t work either. To rotate manually, use the angle field in Window > Gradient.
Now we’re close to what we need. To get a little more random distribution of gradients, we have to randomly rotate only the gradients within the squares anywhere from 0-360 degrees, in 180 degree increments. In this case, this is essentially the same as just rotating 50% of the squares 180 degrees.
I’m again going to use Randomill to do this quickly using the random rotate feature and step size field. However, it can also be accomplished by using a free random select script to select half of the squares, and using Illustrator’s Transform Each tool (found under Object > Transform > Transform Each) to rotate the selected squares 180 degrees. You can repeat that as much as necessary.
Creating the Grid
Now we can start duplicating this result across the entire canvas. Select all of the squares, group them, and duplicate them in a grid pattern until the whole canvas is filled. Since we measured out the square size, and canvas size beforehand, you should end up with a 13x10 grid.
Now we must rotate each group of squares anywhere from 0-360 degrees, in increments of 90 degrees. I’m going to use Randomill again, but you can follow the previous step with random selection and Transform Each to do this without it.
Ok, we’re pretty much there. If you want, you can ungroup everything, and re-apply those initial few gradients across each of these squares and their sub-squares again to really randomize the fill colors. Then repeat the previous couple of steps to rotate the gradients within each square. This will further break up any repetition and make the duplication less obvious.
And there we have it. With just squares, some gradients, and random application of fill color and rotation, we’ve created a pretty complex image. Using Randomill, it took less than 5 minutes.
Feel free to check out the rest of the posters in the series. It's pretty amazing what kind of results you can get with nothing but basic shapes and the power of randomization.