Surrounding Fill allows you to fill the enclosed areas within the selected range with a specified color. Surrounding Eraser removes the fill from the enclosed areas within the selected range. In this example, we’ll use Surrounding Fill and Surrounding Eraser to do the base coloring for an illustration.

* Surrounding Fill / Surrounding Eraser are exclusive features available for Premium Members or users who have purchased the Pro Upgrade.

Open the ①[ Tool Select window ], tap the ②[ Bucket tool ] and select the ③[ Surrounding Fill ].

Roughly trace around the ④[ character’s hair ] with your finger. When you lift your finger, the hair area will be filled with the selected color.

Since areas like ears or hair accessories have also been filled, let’s remove the unnecessary fills. Select the ①[ Surrounding Eraser ].

Roughly trace around the ②[hair accessory] with your finger. When you lift your finger, the fill on the hair accessory will be erased. Repeat this process for other unwanted filled areas.

Now all unwanted fills outside the hair are erased.

Finally, fill the areas like skin, hair accessories, and clothing. With this, the base coloring is complete. As demonstrated, Surrounding Fill / Surrounding Eraser make it easy to apply base colors to an illustration.

①[ Reset ] … Restores all the adjusted parameters to their default values.
②[ Scrape ] … Narrows the range of fill or erasure based on the value set.
③[ Boundary ] … Determines the range to fill based on the similarity with the color at the starting point. You can choose to evaluate similarity using “Color (R, G, B, A)” or only “Opacity”. If the reference layer is a white “Canvas”, the background is fully opaque, so selecting “Opacity” will result in the entire area being filled. If the reference layer is set to “Current Layer” or “Specified Layer”, choosing “Opacity” might be more suitable.
④[ Strength ] … Adjusts how far the fill extends based on the similarity with the color at the starting point.
⑤[ Gap Recognition ] … Neatly fills uneven areas inside the closed lines that are difficult to adjust with the Expansion option.
⑥[ Expansion ] … Further widens or narrows the fill range set with the Strength parameter.
⑦[ Fill from Underside ] … When active, the area inside lines on the current layer is filled without overlapping the lines. When turned off, the fill will overlap the lines.
⑧[ Reference Layer ] … You can choose from “Current Layer”, “Specified Layer”, or “Canvas”. The default is “Canvas”. “Reference” here refers to selecting the layer from which the color is taken to determine the starting point and the fill area. If you select “Canvas”, the combined image of all the visible layers (what you see on the screen) will be used to determine the area. With “Specified Layer”, you can designate a specific layer to refer to when determining the fill area. With “Current Layer”, the current layer is used as the reference. By using “Specified Layer”, you can place the line drawing on Layer 2, set Layer 1 as the current layer, and fill colors separately from the line art.

When using the Surrounding Fill feature, the fill may overflow beyond the lines. This happens because the lines are drawn using brushes with blurred edges, such as the “Dip Pen (Soft)” brush. The more pronounced the blurred edge area of the line, the more noticeable the overflow becomes.

If the fill overflows beyond the lines when using Surrounding Fill, adjust the “Scrape” setting. Let’s take lines drawn with the “Dip Pen (Soft)” brush as an example and try using Surrounding Fill.

The above image shows a fill applied with the default “Scrape” value of 1.0. For a “Dip Pen (Soft) 3px” line, there is no issue. However, for a “Dip Pen (Soft) 16px” line, the fill overflows beyond the outer edges of the line.

Next, the “Scrape” setting was changed to 6.0, and the fill was applied again. For the “Dip Pen (Soft) 16px” line, you can see that the overflow beyond the outer edges of the line has been eliminated.

By adjusting the “Scrape” setting according to the thickness of the lines and the type of brush used, you can achieve cleaner fills and better manage fill removal as needed.