There are many ways to select elements, and it depends on what Mesh Select Mode you are in as to what selection tools are available. First we will go through these modes and after that a look is taken at basic selection tools.
Switching Select Mode¶
When switching modes in an «ascendant» way (i.e. from simpler to more complex), from Vertices to Edges and from Edges to Faces, the selected parts will still be selected if they form a complete element in the new mode.
For example, if all four edges in a face are selected, switching from Edges mode to Faces mode will keep the face selected. All selected parts that do not form a complete set in the new mode will be unselected.
Hence, switching in a «descendant» way (i.e. from more complex to simpler), all elements defining the «high-level» element (like a face) will be selected (the four vertices or edges of a quadrangle, for example).
By holding Ctrl when selecting a higher selection mode, all elements touching the current selection will be added, even if the selection does not form a complete higher element.
Or contracting the selection when switching to a lower mode.
The x-ray setting is not just for shading, it impacts selection too.
When enabled, selection isn’t occluded by the objects geometry (as if the object was solid).
This tool applies an alternating selected/deselected checker pattern. This only works if you already have more than one mesh element selected.
Changes the current selection so that only every Nth elements (vertices, edges or faces, depending on the active selection mode) will remain selected, starting from the active one.
In case of islands of selected elements, this tool will affect only the island of the active element (if there is one), or the island of the first element in the order of internal storage (if there is no active element).
The number of deselected elements in each pattern repetition.
The number of selected elements in each pattern repetition.
Offset from the starting point.
Select All by Trait¶
- Non Manifold
Selects the non-manifold geometry of a mesh. This entry is available when editing a mesh, in Vertex and Edge selection modes only.
Lets you extend the current selection.
Selects all the edges that do not belong to any face.
Selects edges in boundaries and holes.
- Multiple Faces
Selects edges that belong to three or more faces.
- Non Contiguous
Selects edges that belong to exactly two faces with opposite normals.
Selects vertices that belong to wire and multiple face edges, isolated vertices, and vertices that belong to non-adjoining faces.
- Loose Geometry
This selection depends on the currently selected Selection Modes; In vertex and edge selection mode it selects all vertices or edges that do not form part of a face. In face selection mode it selects all faces that do not share edges with other faces.
- Interior Faces
Selects faces where all edges have more than two faces.
- Faces by Sides
Selects all faces that have a specified number of edges.
- Ungrouped Vertices
Selects all vertices which are not part of a vertex group.
Select geometry that has similar certain properties to the ones selected, based on a threshold that can be set in tool properties after activating the tool. Tool options change depending on the selection mode:
- Vertex Selection Mode:
Selects all vertices that have normals pointing in similar directions to those currently selected.
- Amount of Adjacent Faces
Selects all vertices that have the same number of faces connected to them.
- Vertex Groups
Selects all vertices in the same vertex group.
- Amount of Connecting Edges
Selects all vertices that have the same number of edges connected to them.
- Face Regions
Select matching features on a mesh that has multiple similar areas based on the topology.
- Edge Selection Mode:
Selects all edges that have a similar length as those already selected.
Selects all edges that have a similar direction (angle) as those already selected.
- Amount of Faces Around an Edge
Selects all edges that belong to the same number of faces.
- Face Angles
Selects all edges that are between two faces forming a similar angle, as with those already selected.
Selects all edges that have a similar Crease value as those already selected.
Selects all edges that have the same Bevel Weight as those already selected.
Selects all edges that have the same Seam state as those already selected. Seam is a true/false setting used in UV texturing.
Selects all edges that have the same Sharp state as those already selected. Sharp is a mark used by the Edge Split Modifier.
- Face Selection Mode:
Selects all faces that use the same material as those already selected.
Selects all faces that use the same UV texture as those already selected (see UV texturing pages).
Selects all faces that have a similar area as those already selected.
- Polygon Sides
Selects all faces that have the same number of edges.
Selects all faces that have a similar perimeter (added values of its edge lengths).
Selects all faces that have a similar normal as those selected. This is a way to select faces that have the same orientation (angle).
Selects all faces that are (nearly) in the same plane as those selected.
Edit Mode (Vertex or Edge select mode)
Alt-LMB, or Shift-Alt-LMB for modifying existing selection.
Holding Alt while selecting an edge selects a loop of edges that are connected in a line end-to-end, passing through the edge under the mouse pointer. Holding Shift-Alt while clicking adds to the current selection.
Edge loops can also be selected based on an existing edge selection, using either.
In Vertex select mode, you can also select edge loops, by using the same hotkeys, and clicking on the edges (not on the vertices).
The left sphere shows an edge that was selected longitudinally. Notice how the loop is open. This is because the algorithm hit the vertices at the poles and is terminated because the vertices at the pole connect to more than four edges. However, the right sphere shows an edge that was selected latitudinally and has formed a closed loop. This is because the algorithm hit the first edge that it started with.
Edge Loops (All Boundaries)¶
All boundary edges can be selected by performing a second loop select action on a boundary edge.
This can be useful for selecting boundaries for meshes that include triangles and n-gons, where loop select would not otherwise select the full boundary.
Edit Mode (Face or Vertex select modes)
Alt-LMB or Shift-Alt-LMB for modifying existing selection.
In face select mode, holding Alt while selecting an edge selects a loop of faces that are connected in a line end-to-end, along their opposite edges.
In vertex select mode, the same can be accomplished by using Ctrl-Alt to select an edge, which selects the face loop implicitly.
This face loop was selected by clicking with Alt-LMB on an edge, in face select mode. The loop extends perpendicular from the edge that was selected.
A face loop can also be selected in Vertex select mode. Technically Ctrl-Alt-LMB will select an Edge Ring, however, in Vertex select mode, selecting an Edge Ring implicitly selects a Face Loop since selecting opposite edges of a face implicitly selects the entire face.
In Edge select mode, holding Ctrl-Alt while selecting an edge (or two vertices) selects a sequence of edges that are not connected, but on opposite sides to each other continuing along a face loop.
As with edge loops, you can also select edge rings based on current selection, using either.
In Vertex select mode, you can use the same hotkeys when clicking on the edges (not on the vertices), but this will directly select the corresponding face loop…
In Fig. A selected edge loop, and a selected edge ring. the same edge was clicked on, but two different «groups of edges» were selected, based on the different tools. One is based on edges during computation and the other is based on faces.
Convert Selection to Whole Faces
If the edge ring selection happened in Edge Select Mode, switching to Face Select Mode will erase the selection.
This is because none of those faces had all its (four) edges selected, just two of them.
Instead of selecting the missing edges manually or by using Shift-Alt- twice, it is easier to first switch to Vertex Select Mode, which will kind of «flood» the selection. A subsequent switch to Face Select Mode will then properly select the faces.
Selects all geometry along the shortest path from the active vertex/edge/face to the one which was selected.
- Edge Tag (in Edge select mode only)
This select button indicates what should be done when selecting a vertex path with Ctrl-LMB:
Just selects all the edges in the path.
- Tag Seam
Marks all edges in the path as seams for UV unwrapping.
- Tag Sharp
Marks all edges in the path as sharp for the Edge Split Modifier.
- Tag Crease
Marks all edges in the path as creases for the Subdivision Surface Modifier, with weight 1.0.
- Tag Bevel
Gives bevel weight 1.0 (for the Bevel Modifier) to all edges in the path.
- Tag Freestyle Edge Mark
Marks all edges in the path Freestyle feature edges.
- Face Stepping
Supports diagonal paths for vertices and faces, and selects edge rings with edges.
- Topological Distance
Only takes into account the number of edges of the path and not the length of the edges to calculate the distances.
- Fill Region Shift-Ctrl-LMB
Selects all elements in the shortest paths from the active selection to the clicked area.
- Checker Deselect Options
Allows to quickly select alternate elements in a path. See also Checker Deselect tool.
The number of deselected elements in the repetitive sequence.
The number of selected elements in the repetitive sequence.
Offset from the starting point.
Edit Mode (Edge select mode)
Select Loop Inner-Region selects all faces that are inside a closed loop of edges. While it is possible to use this operator in Vertex and Face selection modes, results may be unexpected. Note that if the selected loop of edges is not closed, then all connected edges on the mesh will be considered inside the loop.
Edit Mode (Edge select mode)
Select Boundary Loop does the opposite of Select Loop Inner-Region, based on all regions currently selected, it selects only the edges at the border(contour) of these islands. It can operate in any select mode, but when in Face mode it will switch to Edge select mode after running.
All this is much more simple to illustrate with examples:
Selecting dense meshes with X-Ray disabled, has a limitation where dense meshes may not have all the elements selected.
When selecting regions with Box, Circle and Lasso select, vertices may overlap each other causing some vertices not to be selected.
This is a limitation with the current selection method, you may workaround this by zooming in or enabling X-Ray.
N-Gons in Face Select Mode¶
As already noted, in X-Ray and Wireframe mode faces are marked with a dot in the middle. With n-gons that can lead in certain cases to a confusing display. The example shows the center dot of the U-shaped n-gon being inside of the oblong face inside the «U». It is not easy to say which dot belongs to which face (the orange dot in the image is the object origin).