An introduction to Modifiers in Blender
Modifiers in Blender are very useful modelling tools. This article will explain how modifiers work in Blender.
How modifiers work
The great advantage of working with modifiers is that they allow you to simulate and test changes to a mesh whithout making them permanent until you are satisfied with the result.
The basic steps for working with a modifier are:
- In Object mode, add a modifier to your mesh
- In Object mode you can see what changes it makes to your mesh shape while in Edit mode your mesh stays unchanged.
- Change the modifier parameters and check how the mesh changes.
- Go on editting your mesh in Edit mode, and check in Object mode how the modifier acts upon those modifications you've made.
- Only when you are completely satisfied, apply the modifier and the changes to your mesh will be permanent.
You can add more than one modifier at the same time to your mesh as shown in picture Modifier stack. The order in which modifiers affect your mesh is important and changing the order in which two modifiers apply will most likely lead to different final shapes for your mesh. Modifiers apply following a top-down order, i.e:
- The modifier that is at the top of the stack affects directly your mesh
- The second modifier affects the shape resulting of applying the first modifier to your mesh
- The third modifier affects the shape resulting of applying the first and then the second modifier to your mesh
- and so on
You can change the order or the modifiers in the stack by clicking on the ^ and v little arrow symbols at the right of each modifier, and see how changing the order affects the result.
Some useful modifiers
These are some useful modifiers that you can use in Blender.
The Array modifier creates exact clones of your mesh. It is often used in conjuction with the Curve modifier.
Examples of the use of the Array modifier:
The Bevel modifier smooths the edges that define the outline of a mesh adding at the same time more polygons to it. You can control how much the modifier affects each of the edges by setting the Bevel weight:
- In Edit mode select an edge (or several edges)
- Select the menu option Mesh -> Edges -> Adjust Bevel Weight
- Either move the mouse or type a number to change the Bevel weight for the selected edges. The higher the value, the higher the mesh will be deformed by the Bevel modifier.
Examples of the use of the Bevel modifier:
The Cloth modifier animates your mesh making it move like a piece of cloth. It is very useful for creating hanging clothes like capes, curtains, wide skirts, tablecloths, flags, etc.
Examples of the use of the Cloth modifier:
The Curve modifier is a very powerful modifier as it allows you to work with straight and simple meshes (that are easier to build) and then modify their shape by making they move along a curve creating complex shapes easily. This modifier can be used with open curves and close curves (circles, ellipses, etc).
Examples of the use of the Curve modifier:
The Decimate modifier reduces the polygon count of your mesh while keeping its basic shape. A high polygon mesh will affect the performance of most games, so it is good to reduce its size using this modifier.
If you are going to gmake a UV map for your mesh, apply the Decimate modifier before generating it as this modifier will destroy irt and you'll have to generate a new one. If you have already created the UV map, use the Poly Reducer script instead.
The Mirror modifier is very useful when working with meshes that have a symmetry along a plane as it allows you to build only half of the mesh and Blender automatically creates the other half.
Examples of the use of the Mirror modifier:
The Shrinkwrap modifier allows you to create a low polygon mesh that has the same shape than another mesh.
Examples of the use of the Shrinkwrap modifier:
The Subsurf modifier smooths your mesh shape adding at the same time more polygons to it. You can define how much has subsurf to affect each one of the edges of your mesh. To do this:
- In Edit mode select an edge
- Press the N key and the edge properties window will pop up as shown in picture Setting subsurf intensity on an edge
- look at the Crease value (or Median Crease value if you have selected more than one edge): a vaule of 0 means that it will be completely smoothed by the subsurf modifier, a value of 1.00 menas that it will remain unchanged, and any value between them will represent the percentage the subsurf modifier will affect the edge.
Examples of the use of the Subsurf modifier: