Getting the most out of Civil 3D 2010 - Autodesk

feastcanadianSoftware and s/w Development

Dec 14, 2013 (3 years and 8 months ago)


Nifty Tricks for Civil 3D 2010

Peter Funk

Autodesk, Inc.


This class will show you some of the tricks that can be done with AutoCAD Civil 3D and
AutoCAD 2010.

About the Speaker:

Peter is the Senior Product Manager for Civil 3D® for the AEC Division at Autodesk. In this role, he
helps set the direction of Civil 3D to make it the best software package in the world for civil engineers.
Peter has worked in the
engineering software field for 19 years, starting with DCA Engineering, back
when dirt was young.

Nifty Tricks for Civil 3D 2010



In this class we’ll look at Civil 3D 2010 and I’ll show you some of the tricks that I’ve discovered
that will help you get more out of Civil 3D.

We’ll start with making sure that you get the most out
of your machine then cover surfaces and grading, alignments and profiles, labeling and finish up
with corridor models.

Getting the most out of Civil 3D 2010

I watch the newsgroups almost every day and

notice lots of posts asking “what is the best
computer for Civil 3D?” or about someone’s killer new machine designed for running Civil 3D.
When I look at these post
, I’m scanning for one piece of information: what is the operating

Computers and O
perating Systems

There are

key factors in making a good computer: a solid CPU
, plenty of RAM


operating system

that can take advantage of both of these. Right now the operating system that
we are recommending Windows 7x64 for three reasons: mor
e addressable memory for 32 bit
applications today,

better memory management, 64 bit for the future.

Addressable Memory

32 bit operating systems have a self imposed 4 gigabyte limit to the amount of memory they can
use. This memory is split between the ope
rating system and the application, with 2 for the OS
and 2 for each application.

If you have more than 4 gigs on the machine, then the OS doesn’t
have to swap as much to disk, but each application is still limited to 2 gigs of memory. The
magical “3G” swit
ch can be used in Vista and XP to allow each application 3 gigs of memory,
but this is accomplished by compressing the operating systems into the first one gig of memory
and sometimes that can cause problems.

A 64 bit operating system also runs 32 bit appl
(like Civil 3D 2010) in a 4 gig memory space, but the difference is that the application doesn’t
have to share th
e space with the OS


Civil 3D 2010 would have the full four gigs of memory
to use for your data.

Memory Management

Using an operati
ng system that gives plenty of potential
RAM is the first step,
and then

is having an operating system that can make good use of it. Over the past couple of years we’ve
been looking at the way that AutoCAD and Civil 3D are loaded into memory in diff
operating systems. What we found was that Windows XP tends to spread the application
around the available memory to avoid collusions at load time. While this speeds loading of the
application, you are left with lots of memory pockets for your applica
tion data. When we looked

Vista and Window 7, we see they have sequentially loaded

different parts of Civil 3D into

memory at start time leaving a large contiguous block of memory for your data. These large
blocks of memory are important to the way
AutoCAD works today, because some of the
Nifty Tricks for Civil 3D 2010


operations try to allocate a large block of
, and if it can’t be found AutoCAD will crash
with an out of memory error.


Proxy Graphics

As we watch the out of memory reports that you send us with the
Customer Error Reports
(CER) th
e #1 out of memory is for proxy


The proxy graphics subsystem was written
for small objects (lines, arcs, circles) and not for the massive graphics objects like the surface
model. If you are saving the drawing with p
roxy graphics on

don’t. It will double your file size
and can cause problems.

Layout Cache

If you are plotting lots of layouts in a drawing, make sure

you’re not caching the layouts or you
could run out of memory when you go to plot. There is an AutoCAD variable “LayoutRegenCtrl”
that should be set to either 0 (never cache) or 1 (cache model space and one layout) but never
2 (cache all layouts). While y
ou may think that caching all the layouts would help performance,
we’ve see that it actually can take longer to load a layout with caching that without.


My rule of thumb of for how much RAM to purchase is: “fill every slot on the mother board with
biggest chip you can afford”

Tips and Tricks

We start the tips and tricks with surface and some quick ways to clean up a surface and some
editing tricks to make it look more ascetically pleasing (while maintaining it’s engineering


Cleaning up the outlying triangles in a surface is always a chore, but here are a couple of quick
trick for this cleanup.

Deleting Triangles

by Crosssing

The deleting surface triangle can get monotonous if you do them one at a time. The problem
th the command is that there is a hidden option for

, but you need to type “c” to
activate it. Once the crossing is started, delete triangles will work as it did in LDT (but the
surface contours can dynamically update.

Surface “Shrink Wrap”

always wanted a command that would shrink wrap a surface leaving only the “good
triangles” and getting rid of the outlying ones.
ere is a trick for quickly cleanup a surface

the surfa
ce to use a max triangle length,
extract the re
sulting outer bound
ary as a polyline, add

back to the surface as a new outer boundary, and then switch off the max triangle length. In
Nifty Tricks for Civil 3D 2010


some cases there may be a few holes created in the surface
when using

the max triangle
length, but they will heal up when you finish.


can also edit the polyline either before or after
you add it to the surface to either add or remove vertex points.

Editing Contours

Editing Contours

most people come down on either the “never edit the contour, edit the DTM”
or on the “just let me edit t
he contours”. I’m kind of in the middle

edit the contour, but then add
the edit back into the surface to update the model. The trick to this is to extract a single contour,
edit it in a small region of the surface, and then add it back into the surface a
s a break line or a


Two common questions on surfaces are: how do I get nice smooth contours out of my surfaces,
and how do I edit my contours? With the TIN model
, there are cases where you start getting

long slender saw tooth tria
ngles that
make very bumpy contours.

Smooth Contours

Smooth Contours

you either love them or hate them. In most cases the surface style does
apply smoothing to the contours, but you can

the style or make a new one that uses one
of the two contour
smoothing methods

add vert
exes or use a spline smoothing. One issue
with the spline smoothing is that if the contours are close together, in some cases the spline will
cause them to cross (a bad thing in everyone’s book).

Surface Smoothing

The other way
to smooth the contours
is to smooth the surface! Shocking as it sounds; there are
tools in Civil 3D that will allow a surface to be smoothed using a couple of different algorithms.
For this class we’ll use the “


” and add a gri
d o

points to the
surface. These
points are will turn a TIN

into a smoother

grid based surface

in the area

Note: s
moothing the entire surface will greatly increase the number of points and
triangles in the surface

so be judicious in where and when it is used

This smoother surface will
also produce smoother

Nifty Tricks for Civil 3D 2010



Surface before and after smoothing


Here are a couple of similar tricks that you can use in grading. In
both cases we’ll combine
grading with surface edits.


The first

grade between feature lines to create a pond.

Start by drawing a feature line to represent the botto
m of the pond. The feature line

outline both the bottom of the pond and ha
ve the

elevations. After the feature line is
added, grade the feature line up at 3:1 to a relative elevation of +30. When you create the
grading, make sure you create a surface at the same time.

Next, draw the outer edge of the pond with a second f
eature line. This feature line can be
drawing at zero to start with.

For this to work, the two feature lines need to be on different sites.

After creating the cone of the grading, project the feature line of the outside of the pond to the
elevation of the
grading. This will set the elevations of the feature line to the pond bottom. Then
add the same feature line to the pond surface as an outer boundary to clip the pond bottom


The final step is to grade the outer boundary to the existing ground to c
lose out the pond.

Square Corners

Square corner grading is a request that we here all the time but we haven’t incorporated it into
the product yet. Here is a couple of quick steps that you can do to make a square corner
grading by just using feature lines
and surfaces.

Start by drawing a feature line for the top of the grading.

Nifty Tricks for Civil 3D 2010


Use the “Create Feature Line from Stepped Offset” giving yourself plenty of room to work with

(make sure that the stepped offset will be completely below the existing ground surface
. When
you’re finished, you should have two feature lines.

Next c
reate a new surface called “Corner Grading” and add the two feature lines to the surface
as break lines.

This will form a simple pyramid shape that will be the basis of our grading.

The only
thing that remains is to trim this new surface to the existing ground. It would be nice if
there was a readymade tool for this, but we’ll have to make do with an old trick: make a volume
surface and extract the zero elevation line.

Make the new volume surf
ace using the existing ground and the corner grading surface as your
two target surfaces.

The trick to make this work well is to have a style in your drawing for the volume surface that will
only display the zero line. There are a couple of ways to do thi
s, make a style that only shows
user defined contours and then set the user

contour in the volume surface to zero, or
make a surface that only shows major contours and make sure that the only major contour that
is displayed is the zero line. We’ll
take the second approach. To do this, make a new surface
style called “zero contour”. In the display, only turn on the major contours. For the contour
interval, set the minors at 100 and the majors at 500.

After making the volume surface with the zero lin
e style, you should see the zero line displayed
on the plan. Use the “extract objects” command to pull the zero line out of
the volume surface,
and add it to the corner grading surface as

outer boundary. This will trim the grading surface
to the existin
g ground surface. While this won’t be a dynamic cleanup, it can be semi
automated. If you modify the top feature line, then you need to re create the stepped offset, and
rebuild the surface by erasing the old stepped offset line, and adding the new one. Th
en erase
the old border from the surface and add a new extracted zero line from the updated volume

If you have both

cut and fill conditions, you’ll have to offset the feature line twice, once up and
once down and then use the volume surface zero l
ine twice and combine the results.

Alignments and Profiles

Reversing elements

Sometimes when

you are drawing alignments that are made of separate entities or have been
converted from AutoCAD entities, you find that you can’t add floating or free elements between
them. In many cases this is because the second element is considered “backwards” by t
alignment routines, and a quick flip of the elements will correct the problem.

Nifty Tricks for Civil 3D 2010



Red / Green grid label style

The first two styles that we are going to look at are an elevation marker that will add on a grid
attached to a volume surface. The
cut/fill label will display the cut in Red and fill in Green.



Cut / Fill Grid Drawing

We need to use two tricks to get the labels to display correctly: a number format trick, and an


We will make a new Spo
t Elevation “
Fill Label


Modify the default text component that uses the surface elevation and this number formatting
to show only the positive elevations (fill), by changing the format style to ”hide negative value”.
Change the color of the text compo
nent to green.


Make a copy of the fill text component
, name it “Cut”

and change the color to red.


Make a new expression using the Expression editor shown in


that takes the elevation at
a point, and returns the negative. With this expression, the original negative cut number is not
positive, and the fill number is now negative.

Nifty Tricks for Civil 3D 2010




Expression Editor showing N
egative Elevation

After making the new expression,
modify the “Cut” component to

the label style to use the new
expression instead of the elevation for the value of the label. Use the same “hide negative
values” option. Make sure the two labels are in the
same location if you want them to just
change color, or have the cut above the fill

(as I’ve done)

if you like that option.

Feature Line Elevation Label

Another label request that I’ve seen is something that will label the elevation of each of the
vertex o
f a feature line.
This is easy to do with a label style that the graphics are anchored to
either the start or the end of the line.


Start by making a new label style for line called “Spot Elevation”


Erase all the components from within the label style (the
tag component you won’t be able to


If you want, add a block to the label that will display like a COGO point and anchor the block to
either the start or the end of the line.


Add a text component to the label, anchored to the block element. Into thi
s text component,
add the elevation of the start or end of the line (this should match where you anchored the
component to).


If you want, you can either have the block and the label follow the direction of the line, or they
could always be aligned to the s
heet. You set this on the “General” tab of the label under
“Orientation Reference”

between points

I’ll admit that I’ve never figured out the allure of this comman
d in Land Desktop, but it is

feature that peop
le can’t seem to live without. Years a
go I was taught
that you should always
have reference for the dimension text,
and that
floating text

is bad
My personal objections
, how can we replicate this command in Civil 3D? There are a couple of ways that I’ve
seen: draw a line and label it

using the line and curve labels, and then either

the label
Nifty Tricks for Civil 3D 2010


and erase the line,

make the line invisible
. The problem with the explode method is the label
becomes static, and the problem with the other way is that it becomes hard to find the line

if you need to

A new method is circulating the newsgroup that uses a dynamic block with field
codes, but I don’t like the formatting of bearings with a field.

I’ve got another way: make the line go away by using an

“invisible” linetype

(that isn’t
invisible), using a variation a linetype that we used

at Softdesk in the 1990’s for door and
window headers
Here’s how it work: define a linetype that has a dot at the start, and then
another dot around 20’ out (10 meters) and with an overall lengt
h of 40’ (20 meters). When
drawn, AutoCAD will put a dot at the start and the end of the line, and then another dot every
20’ (10 meters). These dots will allow you to select the line to erase or modify, but they won’t
plot (except as “bug dust”)
even on a

plotted layer. If you put these lines on a “no plot” layer, you
won’t even get the dots.

This same linetype works for both lines and arcs (the arcs may have a
few extra dots near the ends).

The nice thing about this linetype that allowed you to add a line

that is still selectable without it cluttering up the drawing with extra graphics.

The quickest way to create the linetype is to use the Express Tools menu and the “Make
Linetype” command. This command will look at elements in the drawing and create a lin
based on their spacing. For this line type, we’ll need to add a 3 point objects spaced 20’ and 40’
apart. Once the points are added and arrayed in the drawing, run Make Linetype command. The


Zoom to Point
is a command that was added in
the Subscription Advantage Pack for

It works a little different now in that you can enter a point name, point number, or a range
of point names or numbers. If you enter a range, the zoom will encompass all of the points in
the range. ‘ZTP is also a t
ransparent command that you can invoke from within other


With corridors I’ve got two tricks for this year, and oldie but goody, and a new twist.

Surface Editing in Cross Section

The View Edit Corridor Section command was designed to let

you modify the corridor model in
cross section. How it works is the AutoCAD UCS is set to the cross section at the station, and a
very shallow clipping section is added to the view. This produces a very thin cross section of the
model, including the surfa
ce mode
l, and displays the View Edit Corridor Section dialog box. The
key to this trick is to notice that the command line is still active and waiting for input.

Nifty Tricks for Civil 3D 2010


Geometry switches

One of tricky parts of some corridor designs is the number of different cros
s sections that are
needed as conditions change. The typical way that this is done is adding a bunch of corridor
regions and assigning a different assembly to each one, but there is a different way.

We’ve added a couple of different conditional subassembli
es to Civil 3D that allow a single
assembly to react to conditions that it encounters without having a new region.

Wrap Up

I hope that you’ve seen a couple of tricks that you can use for Civil 3D when you go back to the
office, and that I gave you enough
information about computers, operating systems and Civil 3D
to equip you to talk with your IT staff about what is the best setup for the future.