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Meshes Objects

As you have seen above, nearly everything in a 3D view is an “object”. All objects share some common properties. However, each object has a given type, and each type of object has its own specificities. We will talk here about meshes, one of the most complex objects in Blender – so this part will be quite long…

Object mode header.

Edit mode header.

Most actions specific to an object type occur in Edit mode (see above the GUI differences between Object and Edit modes for meshes). Remember that you switch between these modes with ⇆ Tab. Note that for meshes, there are a few additional modes, described later in this chapter (for Scuplt and Weight Paint modes), or in the material/texture parts (for Vertex Paint and Texture Paint modes).

Also remember that after creating a mesh, you may be immediately placed in Edit mode (see object editing for more details).

Two cubes selected prior to Edit mode.

If multiple objects are selected and Edit mode is entered then the last object selected (the active object) enters Edit mode. The other objects remain purple and in Object mode. As shown in image (Two cubes selected prior to Edit mode), both cubes were selected prior to Edit mode and now the left cube is still purple and the right cube (the active one) is in Edit mode.

After talking about some misc topics below, we will first discuss mesh structure and mesh primitives (i.e. the meshes you can directly add to your scene, without any modeling work!).

Then you will see the various ways you can select elements in a mesh, and how to edit this selection.

We will end with various important topics, that are specific to meshes, but often have a larger scope or effect: vertex groups and the related Weight Paint mode, and how to render meshes nicely smoothed.

But first, some important general topics.

Finding Mesh Tools

The mesh tools are located in many places, and you can often find them in several ones (sometimes even under different names!). Here is a non-exhaustive list of the main tools locations:

• The Editing context (F9) – this is the main place, especially the four panels illustrated below:

Mesh Tools.	Mesh Tools More.
Mesh.	Link and Materials.

• The Mesh menu of the 3D view header – it gathers many of the editing tools.
• The Select menu of the 3D view header – it gathers nearly all selecting tools.

Specials menu.

• The “Specials” menus – in fact, there are at least four of them: Specials (W) contains some commonly used tools; Vertex Specials (CtrlV holds some vertex-specific tools; the same goes for Edge Specials (CtrlE) and Face Specials (CtrlF) menus.
• There are many more contextual menus, more specialized, that we will talk about in the relevant pages.

	Keyboard Tip
	You can access the entries in any popup-menu by using the corresponding numberkey (for entries between 1 and [1]0), or Alt-numberkey (entries between 11 and [2]0 – I hope no menu has more than twenty entries!). For example, pressing W and then 1 NumPad will subdivide the selected edges without you having to touch the mouse at all.

Visualization

Cube partly selected.

In Edit mode each vertex is drawn in purple, each edge is drawn in black and each face is drawn in translucent dark-blue. In image (Cube partly selected) the cube on the right is in Edit mode (the cube on the left remained in Object mode).

Each selected vertex or edge is highlighted in yellow (with a lighter shade for the active element – a vertex in Vertex select mode, an edge in Edge one). A selected face is highlighted in translucent purple, and in Face select mode, its selection point is highlighted in orange – the active face being white-dotted.

Hiding Elements

As in Object mode, you can hide what is selected, and then reveal what was hidden. This is very handy to clean up a bit your views, when you are working on a complex model with thousands of vertices…

To hide, use H, the Hide button of the Mesh Tools More panel, or use the Mesh » Show/Hide Vertices » Hide Selected menu option (also available as Hide in Specials menu – W). Note you can also hide what is not selected, using the same Mesh sub-menu, or ⇧ ShiftH.

To reveal what was hidden, use AltH, the Reveal button of the Mesh Tools More panel, or the relevant option in the same Mesh » Show/Hide Vertices or Specials menus.

Mesh Tools More

This panel of the Editing context also has much more visualization options:

Draw Normals and Draw VNormals

When enabled, this will draw respectively the faces and vertices normals, with the length specified in the N Size control just above.

Draw Faces

Enabled by default. It materializes the faces in Edit mode, even in wireframe display, as described above.

Draw Edges

Enabled by default. It always highlight selected edges, even in non-Edge select mode.

Draw Creases

When enabled, it materializes (with their thickness) the crease value of the edges, even when you are not adjusting this Subsurf modifier setting.

Draw Bevel Weight

When enabled, it materializes (with their thickness) the bevel weight of the vertices, even when you are not adjusting this Bevel modifier setting.

Draw Seams

When enabled, it materializes (by outlining them in orange) the edges that are marked as seams (an UVtexturing feature).

Draw Sharp

When enabled, it materialized (by outlining them in red) the edges that are marked as sharp (an EdgeSplit modifier setting).

Edge Lenght

When enabled, it will display the length of all selected edges.

Edge Angles

When enabled, it will display the angles between all selected edges with common vertices.

Face Area

When enabled, it will display the area of all selected faces.

Undo & Redo

Blender has an optional global undo&redo system, as described here, which allows you to cancel nearly every operation (selcting or editing) you just have done. This tool works in Object mode, so it will only allow you to undo a whole edit session in one step.

Editmode Undo History menu.

However, there is also an “edit” history, using the same hotkeys as the global one, for the Edit mode, see (Editmode Undo History menu). This lists all the undo steps by name so you can quickly find your way back to a known good point in your work.

The edit history is kept across switches between Edit and Object modes, as long as you keep the same object active. This means you can switch to Object mode and come back in Edit one without loosing your edit history, if you do not change the active (selected) object.

User Preferences » Edit Methods.

Mesh “Undo” has the potential to be very memory intensive. A mesh of 64,000 faces and vertices can use over 3MBs of RAM per undo step! If you are on a machine that is strapped for RAM (memory), in the User Preferences window under Edit Methods, there is a NumButton for setting the maximum number of undo steps saved, see image (User Preferences » Edit Methods). The allowable range is between 1 and 64. The default is 32.