Modifiers Tutorial
This tutorial covers modifiers.
In this tutorial, you will learn:
- How to add modifiers
- How subobject selection affects modifiers
- How the modifier stack works
- Some useful modifiers
Instructions
Modifiers are accessible from the modify tab. For today's in class work and our lab, we will be starting from a centered box with dimensions 20 20 60 and 6 height segments
Below is the modifiers tab. It is the one with a strange little blue icon in the command panel. Additionally note the modifier list which we will use to add modifiers and the current modifier stack which is currently empty.
We will try adding a modifier. First convert the box to an editable poly. Then add the bend modifier by opening the modifier list drop down and picking bend. Set the angle to 68.5 degrees. Note the effect that this has on the mesh.
Changing the axis parameter will alter the direction through which the effect is applied to the mesh.
Many modifiers have subselections. In this case, if we click the plus sign beside the added bend modifier in the list then select gizmo, we can manipulate the cage that actually applies the bend to the mesh by moving it around. Note that we can also move the center of the bend, though this is not shown.
Modifiers are not always very useful if they can only be applied to the entire mesh. We can select a subsection to apply the modifier to by clicking on editable poly in the modifier stack then activating polygon selection mode. Notice that the effect of the bend is no longer visible. Select the top 4 segment's polygons.
With the selection in place, click on bend again in the stack. Notice now that the bend is applied only to the section that we had selected.
We can make a modifier's changes permanent by collapsing it. This allows us to sub object modify the mesh after the modifier has manipulated it. Right click the bend modifier in the stack and click collapse all. A warning will appear, click yes.
Note now that the modifier stack has been cleared of bend but its effect remains on the mesh.
Applying a new bend, we can see that the effect of the new bend simply modifies the previously modified mesh.
If we don't like the effect of a modifier, we could also delete it. Undo a few times to return to the mesh before we collapsed bend. This time, right click bend and click delete.
Notice now that the selection stack has been cleared of bend, but its effect did not remain on the mesh.
Let's look at other useful modifiers:
Chamfer (breaks down edges similar to chamfer tool):
MeshSmooth (smoothes out a mesh by adding more polygons. Number of iterations controls smoothness):
Optimize (Roughly removes detail. Can be controlled through parameters. Tends to produce ugly results. DO NOT USE OPTIMIZE IN THIS CLASS):
Taper (Linearly makes one side larger and the other smaller based on some parameters):
Twist (Linearly rotates sections of a mesh based on parameters):
Tesselate (Adds more faces to a polygon, note the number of iterations and the fact that we're operating on quads in this example):
Symmetry
Symmetry can be used to mirror existing geometry along a plane. This is useful when working on symmetrical models. The mirror axis can be controlled through the parameters and the mirror's position can be set through the Mirror gizmo.
A good workflow is to add symmetry to an editable poly, set the mirror as desired, then click the "show end result" pipe symbol, then click into the editable poly part of the modifier stack. Note now that even though we're in editable poly state, we can still see the effect of symmetry.
Note now how we can extrude a poly face somewhere and symmetry will take care of replicating the other side for us. When you're done with symmetry, collapse it.
FFD
FFD, stands for Free Form Deform, is extremely useful. It is used to allow us to arbitrarily pull around a mesh provided it has sufficient faces. In this example, we are using FFD 4x4x4; note that FFD 3x3x3, 2x2x2, and custom also exist. The numbers beside FFD indicate how many vertices in each dimension the control cage has.
By activating FFD in the modifier stack, we can select individual control cage vertices and move/scale/rotate them around to modify the overall mesh in a general way.
Note the result after we've moved some of these control cage vertices around. Use FFD when you need to push and pull on an object. Make sure it has enough vertices for FFD to take effect.
