| Creating sharp edges with
auto-smooth |
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The first thing
you'll need for this tutorial is my model of a die, which you can
get here (22k).
Once you have download the model and unzipped it, start
UVMapper Pro and load it. This model has no materials, texture
coordinates or normal vectors. We'll be adding all of these in
the following steps.
It's a good idea when you
start working with a new model to check for and repair concave,
degenerate and collinear facets. You can do this by using the
Tools->Facets menu items. Unless I've made a mistake, you
won't find any of these in my model. |
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We'll start by welding the
vertices (Tools->Vertices->Weld) to be sure we're starting
with a clean slate. Next we'll smooth the model
(Tools->Normals->Smooth) so that we can see what it will look
like when imported into a program such as Poser. The default
setting is "Using all facets" which we want, but to simulate auto
smoothing we'll use a smoothing angle of 180 degrees. After
doing this, your screen should look like the image on the
left. This is pretty much how the model will look if we were
to import it into Poser at this point. To see a before and
after example rendered in Poser,
click here.
Compare this to the image on the left, and the one below
it. |
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Now we'll split the vertices that surround the
holes in the die. Do this by selecting
Tools->Vertices->Split. We want to split using all
facets, a splitting angle of 43 degrees and auto smooth the
model. Since these are the default settings, just click on
OK. By adjusting the splitting angle you can change the
threshold at which hard edges will appear. In this case, any
facets that are facing more than 43 degrees away from each other
will now have a hard edge between them when auto smoothed.
Auto smoothing the model simply does the same thing as
Tools->Normals->Smooth using all facets and an angle of 180
degrees. Your screen should look like this. |
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Press tab to switch to the 2D display.
Select Map->Box and accept the default values by pressing
OK. Right click on one of the facets that make up the white
portion of the die and choose "Select Geometry" from the popup
menu. Your screen should now look like this. Note that
none of the facets that make up the dots are selected because we
split them off in the last step. Since they no longer share
vertices with the rest of the model they aren't part of the same
geometry. This makes it very easy to split up the model for
assigning materials. Choose Tools->Assign to->Material
from the main menu, type in "white" and click OK and then
YES. |
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Pressing control+shift+I will invert your
selection. Select Tools->Assign to->Material again from
the main menu, type in "black" this time and click OK and then
YES. Press the keypad "/" twice to make the selection smaller
and move it to the lower right corner. This way we can map the
dots independently later if we want. Your screen should look
like this. |
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Press tab to return to the 3D view.
Select Tools->Materials from the main menu. Select the
material "black" and click on the diffuse button to change the color
to black. Click on the specular button and choose a medium
gray. Finally, change the shininess to around 400 and click
OK. That's about it for UVMapper Pro. Save your work
using the default settings, and exit. |
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Start your 3D program that uses auto
smoothing. For demonstration purposes I'm using Poser 4.
Load the model and render. Your results should look something
like this. Note: for some reason, Poser seems to ignore the
shininess entry in the material library. I had to go to
Render->Materials, select the black material and set the
highlight size to 100% in order to get highlights to appear in the
black dots. You shouldn't have this problem with other 3D
programs.
And there you have it - a
model in Poser with both smooth and sharp edges without requiring
any additional
facets. |
