Hi folks, thanks for another great session on Saturday.
This week we looked at going beyond the object level and actually editing object meshes. With an object selected you can switch into edit mode by using the drop-down list on the upper left-hand side of the 3D viewport or, more commonly, by pressing the TAB key.
Meshes are made up of three parts:
- Vertices: I tend to also call them nodes, as I did in the diagram below. The represent a point in space
- Edges: A line between two vertices
- Faces: A flat solid area bounded by three or more edges (normally four in Blender)
Faces are also known as polygons. Ones with three sides are called tris (short for triangles), ones with four sides are called quads and ones with more sides are called N-gons. The ends of Blender’s standard cylinder object are examples of N-gons. N-gons can cause strange shading effects when using smooth shading and we try to generally avoid or minimise them.
Editing at the mesh level
Once editing the mesh, all the usual tools that we had available at the object level (namely Move (or Grab), Rotate and Scale) can be used, but now on vertices, edges and faces.
You can work with vertices, edges or faces, as suits what you’re trying to do. To indicate which you want to use, use the buttons towards the top-left of the 3D viewport or the handy shortcut buttons 1, 2 and 3.
The standard cube is too simple to start shaping We saw three ways to add geometry:
- Adding edge loops: An edge loop is a cut that runs cleanly all the way around the object. They are easily added using CTRL-R and then using the scroll wheel to adjust the number of cuts and moving the mouse to indicate which edge you want them to go through.
- Extruding. Select a face and hit the E key, you can then drag it and it will move while newly added faces connect it to its original location. The effect is like forcing Play-Doh through a hole.
- Inseting: Select a face and hit the I key. Move the mouse and you will see a smaller face, the same proportion as the original, is created inside the original face and four more faces connect it to the original edges.
For the second-half of the session, we took a cylinder shape and started to sculpt it into a candlestick shape. A few lessons from that were:
- We started with the simple cylinder and added loads of loop-cuts to allow us to shape the candlestick shape.
- We saw how proportional editing can be switched on to allow vertices connected to those we’re directing editing to be moved as well.
- We saw how the bottom and top of the cylinder are N-gons and look strangely domed when smooth shading is on. We resolved that by insetting the face to minimise the N-gon’s size and extruding it out of the way a bit.
- We saw how adding loop-cuts near an existing edge can restore a sharp edge to our model when smooth shading makes it seem too soft and round.
- We saw how the “Metallic” and “Smoothness” sliders can be used on a material to make it look like shiny metal.
Next week is intended as a free-form session, bring your best ideas for simple projects and we’ll try to help you achieve them. See you then!