Under the first menu, simply named “Freestyle”, you’ll see a sub-dropdown menu, “Edge Detection”. The most interesting parameter there is the “Crease Angle”. This allows you to set the angle between two edges above which a line will not be rendered. The default setting for Crease Angle is 134°, so intersecting edges at 78° will have a Freestyle line applied, although if the same edges were intersecting at 154°, no line would appear in the render.

The highest you can set the Crease Angle is 180°. That will give you a render where all of the edges have lines applied to them. Conversely, you could lower the value for Crease Angle all the way down to zero, which will render with no lines at all.

Freestyle Strokes is a Properties menu full of property menus. Here, you can get really nitpicky about all kinds of details of your line. To get started, under the “Caps” menu, you can select the end shape of the line: butt (flat), round, or square.

Next, you’ll run into “Chaining” settings, which, if selected, will render lines continuously. The default “Plain” means lines are connected together like a chain, end to end, and should suit most purposes. You would need discontinuous lines primarily to change line settings within an object. The following “Splitting” menu would help with defining where line discontinuities occur.

Other interesting settings in this menu can be found under the “Selection” menu, where you can opt to only apply lines of a certain length. Also, under the “Dashed Line” menu, you can set both the Dash and Gap lengths if you are looking for a change-up from the boring solid.

If you are creating characters or animations in Blender, you may not necessarily want all of the edge lines to be black. Luckily, there’s a “Freestyle Color” dropdown menu.

Selecting your “Base Color” is as easy as clicking on the default black color to open up the color wheel. Drag the slider at the right of the box all the way to the top of the scale to reveal the full rainbow. Then, take your pick!

You can even choose from several modifiers that will allow you to get a bit funky with the colors. For example, “Distance from Camera” will allow you to create a color gradient as a function of, well, distance. The “Fill Range by Selection” button under “Distance from Object” is helpful in finding the distance from the camera to the start and end of your object (just make sure you have your object selected).

Line thickness can be adjusted under the “Freestyle Thickness” dropdown menu. You’ll find two options there, as well as modifiers. The “Base Thickness” value allows you to directly adjust the line thickness. With the “Thickness Position”, you can adjust if the lines should be centered or to either side of the geometric edge.

There are plenty of modifiers to choose from that can also provide interesting effects, like “Calligraphy” or “Noise”. You can select the same modifier that we used to create a color gradient, “Distance from Camera”, to produce thicker lines toward the back of the object and thinner lines toward the front, or vice versa.  Each modifier has its own set of parameters that you can tune to your liking, so take some time and play around with each of them!

In the “Alpha” property menu, you can set the transparency of the lines. The default value is 1.0, which is completely opaque.

In addition to this straightforward setting, you have a similar set of modifiers to choose from to really nail down the exact line effect that you are going for. Like the previous menus, “Distance from Camera” and “Noise” are included in the modifier options. A particularly interesting one for setting transparency is “Crease Angle”.

Similar to how the Crease Angle parameter established whether or not a line will be drawn depending on the angle of two intersecting planes, the Crease Angle modifier can be used to set line transparency of the lines according to the intersection angle. This is a nice feature to distinguish between two surfaces intersecting at wide angles without causing smaller angles to appear crowded.

Keep in mind that Blender themselves have stated the Freestyle tool can be very demanding on your computer’s memory. If you’re looking to use Freestyle in one of your projects, it’s not a bad idea to get familiar with the tool using a simple geometry like the Monkey before moving on to heavier renders.

You also have an abundance of resources on YouTube to help you master Blender Freestyle. If you’re planning to use this tool to create anime-style 2D figures, Activemotionpictures created an in-depth video that covers many of the possible properties and modifiers. For a shorter tutorial on cartoon-style lines, Blendera‘s quick tips video on cartoon edges is a worthwhile watch.

If you’re going for something closer to a line art style, then check out the video from chippwalters for a technical example or Head Prism Animation for hand-drawn line stylings.