The Linearity Curve Auto Trace feature allows you to convert images into vector shapes. With Auto Trace, you can create excellent illustrations from a reference photo without tracing the vector shapes by hand.
You can trace images using the three different modes. Each mode contains different parameters that are specifically designed for each image type. This approach will give you optimal results when tracing an image.
How to access the Auto Trace Panel
The Auto Trace Panel is a context-aware menu. It is only visible when you select a raster image. The panel will appear automatically at the top of the Inspector (1) and inside the Top Toolbar (2). Inside the Auto Trace Panel, you can select one of the three following modes:
- A – Photography
- B – Sketch
- C – Illustration
The Auto Trace Button inside the Top Toolbar (2) will enable when you select a raster image.
The Sketch Mode parameters
When you’re in Sketch Mode (1), you have two sliders available that enable you to adjust the following properties:
- A – Complexity. A lower value will group smaller areas and vice versa. Images with a simple composition of shapes (a foreground and a simple monochromatic background, f.ex.) need a lower complexity value. Images with a complex composition of shapes (a foreground with a complex city panorama as a background, f.ex.) require a higher complexity value.
- B – Contrast. The slider defines a threshold at which numeric value a color is considered black or white.
Concerning the contrast slider, a lower value will define more colors as white, and a higher value will define more colors as black.
Click the Auto Trace Button (2) to start tracing your image.
Below you can see examples of different parameter settings. The Sketch Mode generates only a black-and-white vector output.
The Auto Trace feature is a destructive operation, which means that once you convert the image into vectors, you can no longer access and adjust the tracing options. If you want to revert the changes, your only option is to undo the operation.
The Illustration Mode parameters
When the Illustration Mode is selected (1), you will have a menu with a slider, three buttons, and two toggles available that will control the following parameters:
- A – Min Path Size → This slider controls the threshold for your path size. The higher the set value, the longer the path between points will be, and vice versa. The shorter the set path distance between points, the higher the level of detail of the traced image will be. The Min Path Size, for the Illustration Mode, is set to 10 by default.
- B – Level of Details → With this slider, you define the detail level displayed in the resulting traced image. You have the option to choose between Low, Regular, and High. Low will reproduce a traced image with significantly less detail, whereas regular to high will include more detail from the original image in the final vector image.
- C – Simplify Path → If you activate Simplify Path, fewer nodes will be created. The mode is best suited for tracing motifs with simple and uncomplicated lines. If the mode is activated, the tracing process will take less time.
- D – Keep Source Image → If you activate Keep Source Image, the original raster image will be kept and organized below the traced vector image in the layer hierarchy. The original raster image will be grouped with the traced vector image in the Layers Tab.
As soon as you have adjusted the previously mentioned settings, click the Auto Trace Button, and a few seconds later, the resulting vector image will be displayed.
The Illustration Mode only applies to an A12 processor or its corresponding devices, such as the iPhone XR / iPad Air 3rd gen and newer, and M1 MacBooks or higher.
Illustration Mode examples
Below, you can see examples of how the Min Path Size and the Level of Details parameters play an essential role in the final result:
For complex illustrations, we recommend you set the Min Path Size values around 10-20% and set the Level of Detail to High. (For the example below, we set the Min Path Size to 12%)
You can use the Illustration Mode for flat illustrations. In this case, we recommend you to reduce the Min Path Size values to 0% and set the Level of Detail to Low.
You can also use the Illustration Mode for your painting illustrations, as in the example below. In this case, we set the Min Path Size value to 10%, and the Level of Detail to High as the artwork contains several details. Auto Trace will merge all gradients into one color if there's any gradient. You can check the results by activating the Outline Mode.
If you want to learn more about the development process behind the new Illustration Mode feature, read the Interview with our developer Marko.
How to optimize Auto Trace results
We have introduced three new Auto Trace toggles with our latest 4.8.2 update, allowing you to improve your workflow and generate optimal tracing results. The newly introduced toggles are Simplify (1), Ignore White (2), and Keep Source Image (3).
We’ll give you a brief overview below of the attributes and functions. For a better user orientation, the Auto Trace button is now colored in blue.
Auto Trace will create vector shapes with fewer nodes if you toggle on Simplify. This mode is optimal for tracing an image with simple shapes. Activating the simplify mode will significantly reduce the tracing process notably.
Once the Sketch Mode in Auto Trace is activated, you can toggle the Ignore White feature on and off. The new Ignore White feature defines whether Auto Trace converts white image areas to vector shapes. All the white areas of the source image will be erased when Ignore White is turned on while in Sketch Mode.
If you keep the Ignore White toggle turned on , the results of the tracing process are shapes consisting of compound paths. Consequently, any path-related editing will affect the entire compound path structure.
A compound path can be created from two or more open or closed paths. When you create a compound path, all selected paths get organized as Subpaths of a new Compound Path. The selected paths adopt the stroke and fill properties of the object the farthest back in the stacking order.
If you wish to separate the compound paths, select the paths and click the Separate button in the Path section of the Inspector.
If you turn Ignore White off, the paths resulting from the tracing process will be arranged as a group visible in the Layers Panel.
If you activate the toggle Keep Source Image, the original image will be kept after finishing the tracing process. The original image is organized in the layer hierarchy below the traced image. Both images are organized as a group in the Layers Tab.
In this panel (1), you have two sliders available that enable you to set the number of paths and the path size:
- A – Complexity. This slider defines how many paths your vectorized image will contain. Moving your finger along the slider can adjust how many paths your vectorized image will have. A lower number on the slider will result in a more abstract result, and a higher number will produce more detailed paths.
- B – Minimum Path Size. This slider manages the threshold for the path size. A higher value will create longer paths between points and a less detailed image. A lower value will generate shorter paths between points and a higher level of detail.
Once you have adjusted these two settings, click the Auto Trace Button (2) and wait a few seconds for the process to finish.
A testing example of the Auto Trace parameters when using the Photography Mode.
Please note that the Auto Trace feature does not support RGBA images containing an 8-bit Alpha Channel. Auto Trace interprets 8-bit Alpha Channel pixels as black instead of white.
Once you have converted the image into vector shapes, you can edit the paths afterward.
To edit your traced image, add or remove nodes using the Node Tool or go to the Path Section and edit your vectorized shapes by clicking the Remove Nodes button.