3ds Max Modeling Techniques - Topology Freeform Function
This is a 3ds Max multi-part series introducing you to the Topology function found in the Graphite Freeform Tools. The Topology Freeform Function enables you to build a low-polygon model from a high-polygon counterpart. This can be useful when you need to rebuild the geometry for an imperfect model. In this introductory tutorial, learn how to set up the Topology tool and use it to block out the geometry of your new model.
- Recorded in: 3ds Max 2011
- This tutorial is intended for use with 3ds Max version 2011 or higher
In this example, we have a partially built car body and the model
shows a large number of triangular faces.
This may be because the model comes from a different application,
a 3D scanning device or was simply modeled this way.
If you are more partial to models made of Quad polygons,
then the Topology freeform feature is for you.
You can use it to rebuild the model using the following workflow.
Notice in this case that the current model is an Editable Mesh.
In order to access the Graphite Modeling tools, you need to either
convert the model to an Editable Poly or add an Edit Poly modifier to it.
Since the object is symmetrical, it is easier to work on half of it
and then mirror the end results.
In that respect, you can remove half of the existing model
to simplify the workflow.
You don't need to be precise; the high-poly model is only
to be used as a reference.
Start with a simple area, such as the driver's door.
With the car selected, switch to the Freeform tab of the Graphite Tools.
The focus will be on the Topology feature,
which lets you create a surface out of a grid you specify.
By default, this tool creates a surface on the current construction grid,
but it works best when you define an object to base the surface upon,
in this case the car body.
The name of the underlying object appears in the object field.
If you were to use it at this time, the generated surface would be
an element of the existing car body.
Instead, expand Poly Draw and click on New Obj so that the generated
surface is an independent object.
By default, the generated surface will share the same space
as the underlying geometry,
But you can specify a small offset value so that the generated surface
is more easily visible.
A value of 4 should be adequate for this example.
Finally, use the topology feature and start drawing grid lines
on the car door.
Start with the vertical lines, and do not worry about being too precise.
However, if you feel you need to redo one of the grid lines,
then you can delete it by CTRL+clicking it.
Also, if you need to "lift" the action, then you can stop drawing a line,
and then Shift+click to continue it from the closest endpoint.
Once the vertical lines are done, you can lay down
the horizontal grid lines.
The number of lines in the grid determines the number of polygons.
You'll come back to the door in a moment to make further adjustments.
Try the same technique to create the hood.
Draw a few grid lines down the length of the hood, keeping some
of the lines close where you need extra detail.
You can then work on the crossing lines to create the surface.
If your grid lines do not cross, you will get gaps in the surface.
These are easy to fix however.
If you inadvertently remove a grid line using the Ctrl key, you can
always draw it back, even if it is in the inner part of the surface.
To fix gaps, zoom in and extend any short grid lines with the help
of the Shift key.
Ultimately, a right-click ends the process and you are left with the
resulting poly object that you can edit using regular poly editing tools,
now that the basic work is done.
This technique works on more complex areas as well, such as the left
fender, or even organic shapes like characters and creatures.
The real trick is to plan ahead of time how the grid will be constructed.
Remember that to help you draw a grid line; you can always "lift",
and then continue the line using Shift+click.
As you continue working on the fender, notice that the results are on par
with how the grid was created, meaning there are a few hits and misses.
All the glitches can be easily corrected later on
at the poly sub-object level.