I found two tutorials on making retro dots. So either, 1) they're not all that popular, or 2) people are just using the circle selection or brushes to create them. Whichever the case, even if its all of the above or something else, the two tutorials I read on making them were just too complicated to follow and use (and done for Photoshop). A RetroDots plug-in found at Philipp's website is geared for Photoshop, requires PSPI to run in GIMP, and at least for me, is not the whole effect I was seeking.
The example found at this Photoshop tutorial is close to what I want to achieve, but alas, jumping through all these render cloud hoops is just not my thing. Instead, I'll simplify it to suit my use and share that here.
Tutorial YouTube video of the following steps can be found here.
Create your own sized drawing with a white background, then add a transparent layer, name it dot1.
On the transparent "dot1" layer, draw out some rectangle selections of various thicknesses, like shown: (TIP: After making the first selection, hold down the Shift key while creating the subsequent bands)
Select - None
Go to Filters - Distort - Polar Coordinates. Use the following settings and select "OK":
That's the first dot. If you want dots of differing thicknesses, repeat these steps, just draw out your bands thicker or thinner. If the first dot is suitable and you wish to replicate it, no problem.
I believe the brush image size limit in GIMP is 520 x 520 pixels, someone correct me if I am wrong. So if your image drawing size is well over 520 pixels in any direction, we will need to resize the dot layer to fall under 520 in order for it to display correctly
Right click the dot1 layer in the Layers dialog, select Scale Layer. Rescale the image to fall within the 520 x 520 limit. Make sure your pixel ratio chain is linked on the Scale Layer options menu.
Edit - Copy the dot1 layer, if you just want to use this dot for this drawing session only - OR - to make the dot brush permanent, perform the following steps:
Step 3: (permanent brush only - skip this step and go to Step 4 if you just want to make quick, temporary dots)
Right click the dot1 layer and Merge down onto the white background.
Go to Image - Autocrop Image (you should now have an image just the size of the dot):
Go to Image - Mode - Greyscale.
Then on the Layers dialog, right click the layer and select Flatten Image.
File - Save As - (name your file retrodot1.gbr or a name of your choice, just use the .gbr extension).
Make sure to browse to save the brush to your Users .gimp-2.6/brushes folder. You can accept the default spacing of 10, but on the description, in order to get it to show up toward the top of your brushes, add a . (period) before the name in the description (like .dots1)
Refresh your brushes.
Performing these steps allow us to use any foreground color we wish when using the dots brush.
Create a new transparent layer, name it dots2.
If you now look under your brushes menu, you should see the dot1 as the very first image at the top.
The trick for changing colors for the dots is to use "Use color from gradient" and make both the foreground and background colors the same, while using the Pencil tool, Paintbrush tool, or Airbrush tool. Brush away!
Resize the brush scale and change the colors to suit. You can even create multiple layers of dots and change the layer modes or add patterns or adjust opacity levels to get some really sweet effects.
The following is an example of several layers set at different modes (multiply, screen, difference, and overlay). I strongly encourage you to create various layers of different colored dots and set each mode differently just to see the effects it gives.
I thought of making my dots with grunge backgrounds and dot patterns:
Nothing really special here, just 4 layers with a bottom-most layer with grunge pattern background, and 3 multiply mode layers of dots of different sizes. The trick is to use the Color Select tool for each dot layer (selecting the dot), and fill with the Bucket Fill tool, using grunge patterns instead of color.
I hope this helps. Thank you for stopping by.