In this article, we will introduce the Convert feature in Blender.
1. Why You Need to Convert Between Curves and Meshes
1.1 What is “Convert”?
Convert is a feature that changes an object from one type to another. For example, you can convert a mesh into a curve, or convert a curve into a mesh.
Curves are ideal for creating smooth lines, while meshes are suited for detailed editing. By using the Convert feature, you can take advantage of the strengths of both depending on your needs.
1.2 Benefits of “converting” a Curve to a Mesh
- After creating a smooth curve, you can edit it using vertices, edges, and faces, or edit it in Sculpt Mode.
- It allows you to UV unwrap the object and apply textures.
- You gain access to modifiers that do not work well with curves (such as Boolean and Bevel).
- You can convert it to a mesh to export it to other software or game engines (like Unity).
1.3 Benefits of “converting” a Mesh to a Curve
- You can edit smooth curves with fewer edit points (Control Points).
- By duplicating and separating the edges of an existing mesh, you can quickly add parts and decorations along its surface.
- You can adjust the smoothness of the curve, the width when made into a ribbon, the thickness when made into a pipe, and the resolution of the cross-section at any time.
1.4 Things to Keep in Mind When Using “Convert”
There are many benefits when you convert a curve to a mesh (or vice versa), but please note that it is difficult to undo once you convert it.
Before executing Convert, it is recommended to Duplicate the object as a backup using Shift + D.
2. How to Convert a Curve to a Mesh
2.1 Basic Steps to Convert a Curve to a Mesh
Here, we will use a Bezier curve for explanation.
From the Header of the 3D Viewport, go to Add > Curve and add a Bezier (see the image below).
Select the Bezier in Object Mode, and from the Header of the 3D Viewport, go to Object > Convert and select Mesh (see the image below).
This will convert the Bezier from a curve into a mesh.
If you check it in Edit Mode, you can see the vertices as shown in the image below.
2.2 “Resolution Preview U” and Vertex Count After Converting
The number of vertices when you convert a curve to a mesh is directly related to the Resolution Preview U set in the curve’s properties.
The Resolution Preview U dictates the number of subdivisions between Control Points. With the curve selected, you can set this in Properties > Data > Shape (see the image below).
The larger the value of Resolution Preview U, the smoother the curve becomes, and the number of vertices will also proportionally increase when you convert it to a mesh.
If you leave the Resolution Preview U of the Bezier at the default setting of 12 and convert it to a mesh, the segment between the Control Points will be divided into 12 sections, resulting in what you see in the image below.
Alternatively, if you lower the Resolution Preview U of the Bezier to 4 and convert it to a mesh, the segment between the Control Points will be divided into 4 sections, resulting in what you see in the image below.
Setting the value of Resolution Preview U too high will make the mesh incredibly dense and difficult to edit after you convert it, so try to find a value that balances visual smoothness with a manageable vertex count.
2.3 Examples of Converting Curves (Ribbons, Pipes, and Plates)
2.3.1 Convert to a Ribbon Shape Using “Extrude”
By utilizing the Extrude feature, you can easily convert a curve into a ribbon-shaped mesh.
For example, with a Bezier, increasing the Extrude value found in Properties > Data > Geometry (see the image below),
will give you the result shown in the image below.
When you convert this setup into a mesh, it finalizes as a ribbon-shaped mesh as shown in the image below.
2.3.2 Convert to a Pipe Shape Using “Depth”
By using the Depth setting under Round, you can convert the curve into a pipe-shaped (tubular) mesh.
For example, if you navigate to Properties > Data > Geometry > Bevel, select Round, and increase the Depth value (see the image below),
you will get the result shown in the image below.
Once you convert this curve into a mesh, it locks in as a pipe-shaped mesh as shown in the image below.
You can adjust the roundness of the cross-section using the Resolution setting located directly below Depth.
Additionally, ticking the Fill Caps checkbox will cap off both ends with faces.
2.3.3 Convert to a Plate Shape Using “Fill Mode”
By combining 2D curves with the Fill Mode feature, you can convert a curve into a plate-shaped (flat) mesh.
For example, taking a Circle curve, if you select 2D under Properties > Data > Shape and set Fill Mode to Both (see the image below),
it will automatically generate a surface filling the interior of the curve, as shown in the image below.
When you convert this into a mesh, it becomes a flat, plate-like mesh as shown in the image below.
3. How to Convert a Mesh to a Curve
3.1 Basic Steps to Convert a Mesh to a Curve
Here, we will use a mesh Circle for explanation.
From the Header of the 3D Viewport, go to Add > Mesh and add a Circle (see the image below).
With the Circle selected in Object Mode, go to the Header of the 3D Viewport, navigate to Object > Convert, and select Curve (see the image below).
This will convert the Circle from a mesh into a curve.
If you check it in Edit Mode, you can now see the Control Points as shown in the image below.
If the original mesh had 32 vertices, you will find exactly 32 Control Points when you convert it to a curve.
3.2 Spline Types and How to Change Them
Blender supports three spline types for curves: Poly, Bezier, and NURBS. However, when you convert a mesh to a curve, the Poly type is selected by default.
If you wish to change the spline type away from Poly, right-click in Edit Mode to bring up the context menu, then choose Bezier or NURBS from the Set Spline Type option (see the image below).
When you switch from Poly to Bezier, the default Handle Type will be set to Vector (giving you straight lines between points). If you want a smooth, flowing curve, you will need to change the handle type to Automatic or another appropriate setting.
3.3 Fixing Twists After Converting
When converting from a mesh to a curve, the resulting curve may sometimes end up twisted or tilted unexpectedly.
You can visually check for this twist in Edit Mode by clicking Curve Edit Mode in the Header (Viewport Overlays) and checking Normals in the menu.
To fix the twist, select the affected Control Points (you can select multiple) and press Ctrl + T, or adjust the Tilt value under Transform in the Item tab of the Sidebar.
Additionally, pressing Alt + T will instantly reset the Tilt of all selected Control Points back to 0 degrees.
3.4 Meshes That Cannot Be Converted to Curves
Meshes containing faces can be converted into curves, but be aware that all face data will be lost in the process.
Similarly, a solid primitive like a closed cube cannot be directly converted into a curve. However, if you strip it down to just its wireframe (a state without faces, as shown in the image below), it can be successfully converted into a curve.
4. About “Keep Original”
Immediately after executing Convert, an Adjust Last Operation panel will appear in the bottom left of the 3D Viewport. If you check the Keep Original box in this menu (see the image below), Blender will retain a copy of your object in its pre-conversion state, serving as a convenient backup.
That concludes the tutorial on how to use the “Convert” feature between meshes and curves in Blender.
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