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Tutorial:
Erecting a Polygon Building
In this simple
tutorial, you will use the Polygon Duplication and Transformation
tools to create a believable polygonal building simply and
easily (see Figure 7.38).
Figure
7.38 The completed polygonal building.
1.
Start with a Primitive Cube.
Get a primitive
cube and scale it to be twice as tall as it is wide.
Then use the Effect->Subdivide command to chop it
into more polygons that you can use to model in detail.
Set the Polygon Subdivision to 8 in X, 0 in Z (we don't
need detail on the side of the building), and 16 in
Y to create a lot of top to bottom detail. These settings
will create many new polygons we can duplicate and transform
to make windows, exterior detail, doors, and so on.
2.
Add in Roof Detail.
Use the
G supra key (Select by Raycast) to select all the polygons
on the top, front row of the building, but not the roof
(see Figure 7.39).
Figure
7.39 The scaled cube with the subdivision
and roof polygons selected.
Make sure
you are in the Model module and enter POL mode to work
on selected groups of polygons only. Choose the Duplicate->Immediate
command to make a new group of polygons, and then activate
the TransY menu cell. Set the Translation mode to LCL
(local mode) so that the polygons translate on their
local axis, where Y is along the normal.
Translate
the group so that it extends in front as a roof overhang.
When done,
select the top row on the next side of the building,
and repeat. Create a ledge along the top of each side.
Now we'll
create a stepped roof line. Deselect all the polygons
with the Y supra key and the middle mouse button, and
select only the top roof polygons. Deselect the single
polygons on the left and right edge of the roof.
Translate
all the selected roof polygons up a few units above
the roof ledge, creating an angle at the left and right
edges.
Duplicate
the selected polygons and translate them up in Y a bit
to form a roof step. By selecting fewer roof polygons
and then alternating between translating them up without
duplicating them first, you can make a pattern of sloped
and stepped roof segments as in Figure 7.40.
Figure
7.40 The building with a polygonal stepped
roof line.
3.
Add in Front Detail.
Deselect
all the polygons, and then select a strip of polygons
running top to bottom along the front of the building,
two polygons in from the left edge. Select a symmetrical
strip two polygons in from the right edge.
Duplicate
the selected polygons and translate them in Y to extend
a solid concrete detail along the front of the building.
Add a similar
strip of exterior detail in the exact center column
of polygons if you want.
4.
Add Windows.
Start by
selecting only every other polygon in the rows between
the edges of the building and the exterior detail you
just made. Don't select polygons that touch each other
or share a vertex.
Dolly in
(supra key P) in the Perspective view to be tight on
one window so you can precisely adjust your work.
Use Duplicate->Immediate
to create new polygons around the windows, and then
scale the selected polygons in X and Z to become slightly
smaller, leaving a window frame. Translate the selected
polygons slightly into the building.
Duplicate
them again, but this time only translate them into the
building to recess the windows into the face of the
building (see Figure 7.41).
Figure
7.41 One window, duplicated and recessed.
Dolly out
to see that the changes you made to the polygon you
viewed were also made to all the other selected window
polygons. This means that you can add detail to a great
number of polygons at once, saving time and effort.
You may wish to turn smoothing off to see your building
more accurately; do so by entering the Info->Selection
dialog and clicking the Faceted radio button.
As in any construction
site, your building is finished but a mess. To remove all
the unneeded polygons in the building, use the Effect->Cleanup
command. In the Polygon Cleanup dialog box that it brings
up, check the "Merge Polygons if angle smaller than"
option and hit Ok (see Figure 7.42). You can check your work
against the scene named PolyBuilding on the courseware CD-ROM.
Figure
7.42 The completed Wireframe building.
Polygon
Breakup
Ordinarily neighboring
polygons are always connected at each edge because they actually
share that edge, like Siamese twins perpetually joined. In
some cases, however, you may want each polygon to have its
very own edges, unshared with any other polygon in the mesh.
Reasons for this include a desire to offset some polygons,
remove some polygons, or scale some polygons leaving gaps
in the model. An even more common purpose is that when you
plan to blow up a polygon model with the Explode tool, each
polygon must be disconnected from its neighbors so that it
can fly apart on its own as the mesh blows into small bits.
The Polygon->Breakup
tool in the Model module fulfills this role. When it is activated,
you can pick a polygon mesh. The mesh flashes a different
color to indicate that the effect has run, and a new object
is created with the same polygonal structure as the original,
but with no shared edges (see Figure 7.43).
Figure
7.43 The building model, after breakup, with
all polygons translated in Y to show the Exploded view.
