Painting on Polygons:
Anime and Illustrator

By Rick "Flatness" Grossenbacher

Oh, while I’m thinking of it... here is another tip. Draw you face/figure/whatever big enough when you are doing the sketch. It is MUCH better to scale down than to scale up, and Streamline will have an easier time dealing with your lines if it has some room to work with. I leaned this through my own blunders over the years.

Okay, now it is time to scan the sketch into the computer. I scanned mine in as a grayscale image (not black and while line art). One thing you might want to do that I suggest is going over your pencil lines with ink then lightly erasing you pencil lines before you scan, so your lines are better defined. Unfortunately, I didn’t do this so I ended up paying for it with more work on the character by tweaking out the character’s outline in Illustrator. That’s how we learn, I guess.

After you have scanned it and saved it (I saved mine as a .TIF file), you can load up Adobe Streamline. I use Streamline, but you can also use Corel Trace (which I’ve also used and recommend), and I’m sure there are other programs out there. Basically these programs all do the same thing -- they make an outline of your black and white or grayscale bitmap and attempt to turn the lines into Bezier curves and shapes that are editable by vector points in Illustrator.

Load up Streamline, then follow these simple steps:

1. Open you scanned picture from the File menu.

2. Go to the Convert option from the File menu. Then this menu will pop up:

3. Set the Number of Colors to 2 (black & white).

4. Set the Threshold to something that works for your drawing (click the View Sample button to verify your Threshold setting). I set mine to about 32%, but yours could be completely different.

5. When you are happy with your Threshold, press the Convert button.

6. Under the View menu, check Preview Illustration so you can see what Streamline did to your graphic.

Remember that this is just a preview so it is showing it worse than it actually is.

7. Save that baby and fire up Illustrator.

Now that it has been successfully turned from a bitmap into a vector image you can start fixing all the lines that Streamline freaked-out on (which happens a lot unfortunately). The darker your original lines are on your sketch, the better job Streamline will do, and the less hassle for you in the long run.

So now I’m going to zoom in and go over my picture with a fine tooth comb and find every little quirk and make all the lines as flawless as possible. Sometimes this involves adding or extending lines and shapes, or simply just adjusting Bezier curves. Here is a zoomed up view of some curves I’m correcting:

This is the most time consuming part of the process. Look over you drawing carefully. Some parts might need to be moved or angled or connected to other parts. Eventually, you will get to this point and all the lines are looking nice:

Also, notice that I’ve done some major reshaping and fixing to the eyes, nose, and mouth.

Now it is time to start coloring. You could really do this step in either Photoshop or Illustrator. Personally, I prefer Illustrator for this type of coloring.

Your choice of colors are of course dependent on what kind of picture you are creating, but for the Anime guy, I chose to use three colors for the skin that weren’t too saturated.

When I’m applying color to a streamlined picture, I approach it in nearly same manner as cel animators have paint applied to their characters. They paint on the back of the celluloid so when the cel is flipped right side up, the black outline of the character is always on top of the color and the color never bleeds into the crisp, beautiful lines they’ve drawn.

I do it like this in Illustrator, but opposite (if that made any sense). I start a new layer for each new color, then instead of drawing beneath the black line, I draw the color right over top, and into black line (sometimes past the black line). Then, I just drag the color layer underneath the black line layer, and boom-bam it’s colored.

Now I’ll zoom up so you can see how I’ve done it with a second color.

I have a black outline selected (in blue). See how the color is extending past the black outline? Notice how it is going into the hair a little bit? That doesn’t matter because when I start drawing in the color for the hair, I’ll just paint right over top of the skin color. Now you are probably saying, "what’s the point? In Illustrator you can fill in colors in any closed shape, right?" Yes, this is true, but remember, this picture was Streamlined, and unfortunately Streamlining does funky things to your images. More often than not, Streamline will make the black line in your drawing into a shape (not a line), so when you try to fill in the white areas, Illustrator can’t do it because there is no shape there to fill; it’s just the negative space (the background). Or, sometimes Streamline will connect shapes that you don’t want to be connected so when you try to fill it with a color, it will fill unwanted areas. Ugh! It’s annoying, but not too tough to deal with once you get the hang of it.

Now I’m going to continue to add more colors to the skin for shading.

Looking good. The skin is done, so now I’m going to do the hair.

I also threw some highlights on the hair to give the picture some depth. Note that these don’t have black outlines around them. Generally, you don’t want to do that to a highlight as it will just look out of place.

Finally, the coloring is done! I made his hair green for no real particular reason other than I like it that way. Now I look over my image and make sure everything is where I want it. Maybe move the eyebrows up or down, or the mouth, or whatever. Experiment and see what looks best.

So, that’s it! This process may take some time to get used to because manipulating curves in Illustrator can be quite frustrating at times. It can be even more so with a Streamlined picture because Streamline doesn’t always set your lines and Bezier curves to the way you want them. Just keep at it, and you’ll get the hang of it. Good luck with your artwork!

- Rick Grossenbacher is a professional 2D artist and graphic designer. Amongst other things, he has worked on the upcoming title Daikatana from Ion Storm, and done freelance work for RCA and Sony records.