Quick tutorial: Create a vector displacement stamp from an existing model
When it comes to creating highly detailed stamps and stencils to be used in a sculpting workflow, the vector displacement method in Mudbox cannot be beaten
Vector displacement stamps can help you create stunning surface effects with ease
For the creation of stamps and stencils, vector displacement requires that the target mesh must have the same topology as the source mesh.
There are a few tricks for achieving this. Once you understand the process, creating a stamp is easy.
The key to creating a vector displacement map from existing geometry (or from a portion thereof) is to create a regular displacement map as a starting point.
Mudbox provides two ways to do this: via the map extraction UI, for more accurate results using a higher bit-depth image format; and directly within the viewport filter, for quicker results.
Let’s take a look at both methods.
First, create a simple plane by selecting Create > Mesh > Plane.
Leave the default settings for the plane as they are. This plane will be your background for baking the displacement map.
Next, import your model via File > Import.
In this example, we’re using a model of an old, beaten-up car. Be sure the model is placed at the origin, facing up in the Y axis.
Any details you wish to capture in the map should be pulled up above the plane. Use the transformation tools in the Select/Move Tools tray if your model is not positioned in this manner.
Everything above the plane is included in your ultimate displacement stamp
Viewport filter method
For the ‘quick and dirty’ method to create a simple displacement map, go to the Object List tab (top right corner beside the Layers tab).
Right-click on the Top camera and select Look Through. You’re now looking down the Y axis.
Zoom in and frame the plane to within the boundaries of the viewport.
You can also pull the edges of the viewport to fit the exact square-shape of the plane as well.
Next, go to the Viewport Filters tab (in the top-right corner by the Layers and Object List tabs) and toggle Screen Distance on.
Click the Save 16-bit Image button in the Screen Distance Properties tab and select a location to save.
For other image formats, select Render > Save Screen Image and select the resolution, image format and save location.
This method is fast and effective, but it’s limited to working with 8-bit images. The higher the bit depth of the image is, though, the more accurate the data from the model will be, yielding better results in your stamp.
That’s where the alternative method for creating a displacement map comes in.
Map extraction UI method
To use a higher-bit-depth image to store more detail, first select Maps > Extract Texture Maps > New Operation. Select Displacement Map.
To create your stamp, bring in any existing geometry you like, then scale, rotate and position it within your stamp area to establish the design
In the Target Models space, click Add All, then highlight and remove everything else except plane.
In the Source Models space, click Add All; this time, highlight and remove the plane.
In the Search Distance box, click Best Guess for an appropriate envelope to calculate the sampling. Select your image size. (1K is fine for most circumstances: remember you are just using this map as a starting point to sculpt with.)
Down in the Base File Name box, click the envelope icon, select your path and then choose an image format.
The higher the bit depth, the more detail you will preserve in the map.
Import the displacement map
Now select File > New Scene followed by Create > Mesh > Plane. Subdivide the plane up a few levels (to at least Level 6).
Import your displacement map as a stencil into the Stencil tray by selecting the arrow icon and then Add Stencil.
Select the Sculpt Tool and then use the [S] key to position the stencil over the plane. Create a new sculpt layer.
You will need to adjust the strength of your Sculpt Tool to displace the geometry to the closest depth of the
Once you’ve used the displacement map to re-create the base model shape, it’s up to you to sculpt and change the mesh to your desired effect.
In the video, I show a displacement map that I use as a base mesh compared to a final vector displacement map.
The regular displacement map provides a starting point for some simple sculpting.
Don’t be afraid to use the Pose tools to bend or twist the geometry as well. Vector displacement is accurate for storing overhanging and undercutting geometry, as well as very smooth or fine details.
After you import geometry for your stamp, pay attention to its subdivision level: you may need to increase it to remove any faceting.
Watch the accompanying video for this Mudbox tutorial.
By Craig Barr
Technical marketing specialist at Autodesk
on Thursday, July 7th, 2011 at 5:20 pm under Technique, Tutorials.
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Tags: Autodesk, Mudbox, tutorial, vector displacement