- In the Top viewport, create a line. Give the line two vertices, one
at each end. Click at the left side of the viewport to start the line.
Move the cursor to about 3/4 of the width of the viewport. To set this
vertex, click and drag to the right until the cursor reaches the right
side of the viewport.
- Release the mouse, then right-click to end the line.
- Create a small circle to loft along the line.
- In the Top viewport, make five copies of the line. Spread the copies
out so you can see them easily. Be sure to leave enough space between
the lines so you'll be able to see the lofts when you make them
later.

- Select the first line. Go to the Modify panel. Expand the
Line listing and highlight the Vertex sub-object level to
access it.
- Select the line's rightmost vertex. Right-click on the vertex. The
Quad menu appears.
The four possible vertex types appear at the
left side of the menu, with a checkmark next to the one that is
currently chosen.
Smooth - Forces the segments into a
smooth curve. Corner - Makes the segments straight as they
leave the vertex. Bezier - Provides a tangent line and small
green handles that can be moved to change the shape of the curve around
the vertex. The handles always move together to keep the line straight
and tangent. Bezier Corner - Provides handles which can be
moved independently to make a sharp corner, smooth curve or any shape.
The current vertex type should be Bezier. If it is not,
you will need to start over from step 1. Otherwise, you won't be able to
simulate the bad effects in later steps.
- On the Quad menu, choose the Corner type.
- Turn off the Vertex sub-object level by clicking on the main
Line level.
- Select the second line. Access the Vertex sub-object level
and select the line's rightmost vertex. The Bezier handles appear around
the vertex. Leave this line as is. Return to the Line level of
the object.
On the remaining lines, you will need to access the
Vertex sub-object level to work with the vertices, then return to
the Line level before you can select the next line.
- Select the third line and select the line's rightmost vertex. The
Bezier handles appear. Zoom in to the vertex and handles. Click on
Select and Move and turn on Restrict to X. On the left
handle, click and drag to the right until the handle is almost on top of
the vertex.
- Select the fourth line. Select the line's rightmost vertex. Pick up
the left handle and move it close to the vertex. Move the handle up a
little so the line between the handles goes at a slant.
The
handles must be quite close to the vertex in order to make them slant
while still keeping the line straight. You might have to zoom in pretty
close to get this effect.
- Select the fifth line. Pick up the left handle and move it up and
over to the other side of the vertex until the line between the handles
goes straight across horizontally. The original line that you drew
should go straight across after you've placed the vertex.
- Copy the fifth line to make a sixth line below the fifth
line.br>
Now you're ready to loft.
- Select the first line. Go to the Create panel and make sure
the Geometry button is clicked. Select Compound Objects
from the pulldown list, and click Loft. Click the Get
Shape button and click on the circle.
Expand the Skin
Parameters rollout and check the Skin checkbox.
You
should be able to see the lofted object in all viewports, and it should
look fine.
- Select the second line, and loft the circle on it in the same
manner. Repeat for each line until you have six lofts.
Now take a
look at the lofts. You should observe the following: Second and third
lofts - Segments are unevenly distributed Fourth loft - One end has a
slant Fifth loft - One end looks as if is has been pinched and folded
over
The sixth loft looks just like the fifth loft. To observe
some different effects, select the sixth loft object (not the line, but
the loft object itself) and go to the Modify panel. Under the
Skin Parameters rollout, change the Path Steps to
different values such as 10, 20, 30, 40, 60 and 100. Observe the loft
object as you make each change. With some Path Step values, the
end of the loft juts out in a big spike.
Next, we'll fix these
lousy lofts.
- Select all the loft objects, but not the lines. Go to the
Display panel and click Hide Selected to hide
them.
- Select the second line. Go to the Modify panel. Go to the
Vertex sub-object level and select the rightmost vertex.
Right-click on the vertex and change its type to either Corner or
Smooth. Return to the Line level.
- Repeat this process for each line.
- Go to the Display panel and click Unhide All.
The lofts appear, and they are all fixed now. Note that you
changed the loft simply by changing the existing line being used for the
loft.
From this tutorial, you should be able to see that
Bezier vertices make lousy end vertices for a loft object, while
Corner and Smooth work just fine on the ends.
Bezier vertices work great as middle vertices, though.
The next time you do a loft, check the ends of the loft path to
make sure the end vertices are either Corner or Smooth
types, and all will be well.
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