Extrude
 | WARNING THIS CONTENT HAS BEEN IMPORTED AUTOMATICALLY FROM 2.0 GUIDE -MIGHT BE OUTDATED AND/OR INACCURATELY CONVERTED |
The most important tool for working with Meshes is the "Extrude" command (EKEY). This command allows you to create cubes from rectangles and cylinders from circles. Extrude allows you create things such as tree limbs easily. Although the process is quite intuitive, the principle behind Extrude is outlined below for your information:
First, the application determines the outside 'edge' of the Extrude, i.e. which selected edges are allowed to be changed into faces? By default, the application ignores edges with two or more selected faces.
The edges in question are then changed into faces.
If the edges in question had only one face, all of the selected faces are duplicated and linked to the newly created faces, e.g. rectangles result in cubes during this stage.
In other cases, the selected faces themselves are linked to the newly created faces. This prevents undesired faces from being retained 'inside' if Extrude is invoked again later. This distinction is extremely important, e.g. during smoothing. The distinction ensures the construction of consistently coherent, closed volumes at all times when using Extrude.
Edges without selected faces are simply Extruded.
Vertices without selected edges are turned into edges.
Grab mode is automatically started when Extrude is invoked. Extrude is one of the most often used modeling tools in Blender. It's simple, straightforward and easy to use, yet very powerful. In this tutorial you'll learn how to use Extrude to model a sword in a very short time.
The Blade
Start Blender and delete the default plane. In top view add a mesh circle with 8 vertices. Move the vertices so they represent the figure below.
Select all the vertices and scale them down with the SKEY so the shape fits in 2 grid units. Switch to front view with Keypad_1.
The shape we've created is the base of the blade. Using extrude we'll create the blade in a few simple steps. With all vertices press EKEY, or click the button labeled `extrude' in the editbuttons (F9). A box will pop up asking `Ok? Extrude',
click it or press enter to confirm. If you move the mouse now you'll see the following has happened: Blender has duplicated the vertices, connected them to the original ones with edges and faces, and has entered grab mode. Move the new vertices up 30 units, constraining the movement with CTRL. Click the left mousebutton to confirm their new position and scale them down a little bit with the SKEY.
Press EKEY again to extrude the tip of the blade. Move the vertices five units up. To make the blade end in one vertex scale the top vertices down to 0.000 (hold CTRL for this) and press WKEY>'Remove Doubles' or click the `Rem Doubles' button in the editbuttons (F9). Blender will inform you it removed seven of the eight vertices and only one vertex remains: the blade is done!
The Handle
Leave edit mode and move the blade to the side. Add a UVsphere with 16 segments and rings and deselect all the vertices with the AKEY. Borderselect the top three rings of vertices with BKEY and delete them with XKEY>'Vertices'.
Select the top ring of vertices and extrude them. Move the ring up four units and scale them up a bit, extrude and move 4 units again twice and scale the last ring down a bit. Leave editmode and scale the entire handle down so it's in proportion with the blade. Place it somewhat under the blade.
The Handguard
By now you should be used to the `extrude>move>scale' sequence, so try to model a nice guard with extrude. Start out with a cube and extrude different sides a few time, scaling them where needed. You should be able to get something like this:
After texturing the sword looks like this:
As you can see extrude is a very powerful tool allowing you to model relatively complex objects very quickly (the entire sword was created in less than a half hour!). Getting the hang of the extrude>move>scale will make your life as a Blender modeler a lot easier.