Quicksurf Dokumentation Englisch

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Quicksurf

Version 5. 1

Surface modeling.

Copyright 1998 Schreiber Instruments, Inc.

All Rights Reserved

Schreiber Instruments, Inc. makes no warranty, either expressed or implied, including but not limited to any implied warranties of

merchantability or fitness for a particular purpose, regarding these materials and makes such materials available solely on an "as

is" basis. In no event shall Schreiber Instruments, Inc. be liable to anyone for special, collateral, incidental, or consequential dam-

ages in connection with or arising out of the purchase or use of these materials. The sole and exclusive liability to SchreiberInstruments, Inc., regardless of the form of the action, shall not exceed the purchase price of the materials described herein.

Schreiber Instruments, Inc. reserves the right to revise and improve its products as it sees fit. This publication describes the state

of the product at the time of publication, and may not reflect the product at all times in the future.

Quicksurfis a trademark of Schreiber Instruments, Inc. 3D Studio and AutoCAD are registered in the U.S. Patent and Trademark

Office by Autodesk, Inc. All other tradenames or trademarks are gratefully acknowledged as belonging to their respective owners.

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Contents

Quicksurf i

Chapter 1: Introduction

About Quicksurf .................................................................... 1

Chapter 2: Installation

System software requirements............................................... 9

System hardware requirements.............................................. 9

Required knowledge.............................................................. 9

Quick installation................................................................ 10

Installation ...........................................................................10

CD ROM installation .................................................... 10DOS Installation............................................................ 10

Windows Installation ....................................................14

Hardware keys ..................................................................... 17

Network considerations .......................................................18

Customer support.................................................................19

Chapter 3: Concepts

Whats a surface?................................................................. 21

Surface memory ............................................................ 22Parts of a Surface................................................................. 24

Data parts ...................................................................... 25

Calculated parts............................................................. 26

Break lines..................................................................... 30

Contours ........................................................................ 34

Grid Methods .......................................................................35

Continuous Curvature (Standard method) ....................35

Trend surfaces............................................................... 35

Kriging ..........................................................................36

Chapter 4: Quicksurf menus

............................................................................................. 37

Chapter 5: Quick Start

Introduction ......................................................................... 43

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Loading the Quicksurf menu................................................43

Quicksurf demo mode ..........................................................44Loading the demo data set....................................................44

Displaying a surface.............................................................46

Examining surfaces in 3D ....................................................50

Draping a polyline................................................................51

Generating a profile..............................................................52

Examining new surface parts ...............................................53

Using Boundaries .................................................................54

Annotating your map............................................................57

Drawing the contours.....................................................57

Indexing the contours ....................................................58Labeling the contours ....................................................58

Posting Z values of points .............................................59

Chapter 6: Command Reference

Organization.........................................................................61

Data input .............................................................................61

Extracting drawing data.................................................62

Reading ASCII data files ...............................................65

Data Export ..........................................................................79

Exporting ASCII data files ............................................79

Exporting 3D Studio files ..............................................81

Surface commands ...............................................................82

Show versus Draw.........................................................82

Surface modification ............................................................93

Surface Options .............................................................94

Surface viewing....................................................................95

Boundaries............................................................................99

Annotation..........................................................................102Color control ......................................................................114

Surface colors ..............................................................114

Surface Color Sequence...............................................122

Set SHOW Color .........................................................129

Contour colors .............................................................130

Volumetrics........................................................................133

Design Tools ......................................................................143

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Utilities .............................................................................. 167

Elevation utilities ........................................................ 167Quicksurf utilities........................................................ 171

Polyline utilities ..........................................................182

Polyface utilities.......................................................... 184

General utilities...........................................................185

Chapter 7: Configuring Quicksurf

Configuration files............................................................. 195

List Configuration .......................................................196

Read Configuration .....................................................197Save Configuration .....................................................197

Factory Configuration ................................................. 197

Version Info ................................................................ 197

Configure Grid................................................................... 198

Grid Method................................................................ 201

Trend method of gridding ........................................... 203

Krige method of gridding............................................ 205

Configure Contour............................................................. 207

Configure Drape ................................................................ 211

Configure Breaks............................................................... 213

Configure Extract ..............................................................214

Configure Boundary .......................................................... 218

Configure Units ................................................................. 219

Configure Camera.............................................................. 220

Configure Post ................................................................... 221

Configure ASCII Load ......................................................223

Configure Slopes ............................................................... 225

Configure Section.............................................................. 230

Configure Surf Ops............................................................ 237

Chapter 8: Surface Operations

Introduction ....................................................................... 239

Surface operations dialog box ........................................... 239

Surface list................................................................... 240

Surface management buttons ......................................241

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Mathematical operation controls .................................246

Surface management functions....................................247Surface modification operations ........................................250

Grid geometry operations ............................................250

Surface modification operations..................................254

Mathematical surface operations........................................256

Understanding surface operations ...............................256

Mathematical surface operators ...................................260

Chapter 9: Boundaries

Boundary smart commands................................................269Establishing boundaries .....................................................270

Nested boundaries ..............................................................271

Boundaries and surface displays ........................................271

Chapter 10: Break lines

Creating break lines............................................................273

Adaptive densification .......................................................274

Resolving break lines .........................................................275

Intersecting break lines................................................276

When to use break lines .....................................................276

Chapter 11: Drape

Concepts.............................................................................279

Drape basis ..................................................................279

Drape step ....................................................................280

Draping off the edge of a surface ................................280

Drape and Boundaries .................................................281Using Drape .......................................................................281

Solving for an elevation...............................................281

Creating a 3D profile ...................................................282

Constructing design elements (break lines).................282

Converting 2D maps to 3D maps ................................282

Application examples.........................................................283

Drape and post points ..................................................283

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Horizontal arc to vertical curve................................... 284

Hatch pattern draped on a surface............................... 285

Chapter 12: Surface editing

Examining the raw data.....................................................287

What is an edit point? ........................................................288

Adding edit points ............................................................. 289

Editing contour polylines................................................... 291

Correcting slope excursions............................................... 292

Chapter 13: Site planning workflow

Workflow Overview..........................................................295

Chapter 14: Volumetrics

TIN based volumetrics....................................................... 297

Volume under a triangle.............................................. 297

Volume under a surface .............................................. 299

Understanding volume calculation ....................................300

Workflow .................................................................... 301

Volume by Entity............................................................... 303

Volume calculation from surface memory ........................ 305

Volume calculation options ........................................ 305

Running a volume command ...................................... 309

Surface volume ........................................................... 310

Area Volume............................................................... 310

Boundary Volume....................................................... 311

Practical volume calculations ............................................ 312

Comparison to Average End Area volumes................ 314Common volume calculation mistakes ....................... 315

Chapter 15: Surface estimation methods

Supported methods ............................................................ 317

Triangulated Irregular Network (TIN)....................... 317

Slope-based methods................................................... 318

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Geostatistical methods .................................................319

Which method do I use?.....................................................320Workflow.....................................................................320

Data types and surface methods .........................................321

Chapter 16: 3D Studio meshes

Exporting mesh objects ......................................................323

Direct surface export ...................................................323

Subdividing surfaces....................................................324

Morphing Quicksurf surfaces.............................................325

Chapter 17: User coordinate systems

Extract commands and User Coordinate Systems .............327

Chapter 18: Working with extracted contours

Objective ............................................................................329

Workflow ...........................................................................329

Extracted contours tutorial .................................................330

Extracting the contours ................................................330

Correcting slope problems...........................................331

Correcting short-cutting contours................................331

Edge effects .................................................................334

Chapter 19: Pad construction

Objective ............................................................................335

Workflow ...........................................................................336

Pad construction tutorial ....................................................337

Chapter 20: Pond construction tutorial

Objective ............................................................................343

Workflow ...........................................................................344

Pond construction tutorial ..................................................345

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Chapter 21: Ditch construction

Objective............................................................................ 355

Workflow........................................................................... 356

Ditch construction tutorial................................................. 357

Chapter 22: Wall construction

Vertical discontinuities ......................................................364

Workflow........................................................................... 365

Chapter 23: Road construction

Objective............................................................................ 367

Workflow........................................................................... 368

Road construction tutorial ................................................. 369

Chapter 24: Slope analysis

Objective............................................................................ 385

Workflow........................................................................... 385

Slope analysis tutorial........................................................ 386

Chapter 25: Contaminant modeling

Overview ...........................................................................391

Mapping contaminant iso-concentrations.......................... 391

Chapter 26: Using Kriging

Introduction ....................................................................... 395

Objective............................................................................ 397

Workflow........................................................................... 397

Using kriging ..................................................................... 397

Chapter 27: Geologic faulting

Introduction ....................................................................... 407

Constructing fault break lines............................................ 409

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Workflow ...........................................................................410

UsingDrapeandExtrapolate ............................................414

Chapter 28: Architectural uses

............................................................................................417

Chapter 29: Configuration files

............................................................................................419

Chapter 30: Keyboard equivalents

Data input ...........................................................................423

From the drawing.........................................................423

From ASCII... ..............................................................423

Data Export ........................................................................423

To ASCII.. ...................................................................423

To 3D Studio.. .............................................................423

Surface commands .............................................................424

Boundaries...................................................................424

Create / Display ...........................................................424

Modify .........................................................................424

Viewing .......................................................................424

Annotation..........................................................................424

Color control ......................................................................425

Volumes .............................................................................425

Design Tools ......................................................................425

Utilities ...............................................................................425

Elevations ....................................................................425

Quicksurf .....................................................................426Polylines ......................................................................426

Polyfaces......................................................................426

General.........................................................................426

Surface operations..............................................................427

Surface management....................................................427

Surface modification....................................................427

File operations .............................................................427

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Mathematical operations............................................. 428

Chapter 31: Trouble shooting

Program doesnt run.................................................... 429

Menu misbehavior....................................................... 429

Data import problems.................................................. 430

Extract problems .........................................................431

Display problems ........................................................ 431

Speed problems ...........................................................432

Grid problems ............................................................. 433

AF pager error ............................................................. 433Annotation Problems................................................... 433

Lengthy Auto Densification........................................434

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13/456About Quicksurf Page 1


About Quicksurf

Quicksurf is a fast, powerful general purpose surface modeling

system running inside of AutoCAD Release 12,13 or 14. Thou-

sands of people use Quicksurf daily for generation and annotation

of contour maps, profiles, sections and volumetric computation.

Quicksurf converts surface mapping data such as point or breakline data into contours, grids, triangulated irregular networks

(TIN), and triangulated grids (TGRD (pronounced tee-grid)). A

suite of sophisticated tools allows you to manipulate modeled

surfaces into high quality finished maps and perform a variety of

engineering computations.

Quicksurf meets the needs of a broad range of professional disci-

plines such as civil, environmental, petroleum and mining engi-

neering, geologic mapping and exploration, surveying,

photogrammetry and topographic mapping, landscape architec-

ture, oceanography and surface visualization.

Quicksurf was designed to operate seamlessly with all AutoCAD

applications software. Written in C, Quicksurf is the fastest mod-

eling package available running inside of AutoCAD. All of the

three-dimensional models produced by Quicksurf are completely

compatible with 3D Studio and other three dimensional visualiza-

tion packages.

There is no limitation on the number of points or the number of

surfaces which may be manipulated simultaneously. Quicksurf

utilizes AutoCADs virtual memory, so the size of your project is

limited only by the available hard disk space. Some Quicksurf

users have built maps containing over 10 million control points

on the PC platform.

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Page 2 Introduction

Quicksurf 5 is available in versions for DOS, Windows, and Win-

dows NT running AutoCAD Release 12, 13, or 14.

Input

Data may be input from a wide variety of sources to Quicksurf

including:

ASCII files of X,Y,Z point data

ASCII files of X,Y,Z polyline (break line) data

Extracted from any AutoCAD drawing entities

Direct import of digital elevation model (DEM) data

X,Y,Z point information may be extracted from AutoCAD points,

vertices, 2D polylines representing contours or break lines, verti-

ces of 3D polylines representing break lines or profiles, as well as

most other drawing entities.

Output

Data generated within Quicksurf may be saved in several ways

including:

AutoCAD drawing entities: Entity drawn

Points points

Triangulated Irregular Networks (TIN) lines or meshes

Grids points or meshes

Triangulated Grids (TGRD) lines, or meshes

Contours 2D polylines

Profiles and sections 2D or 3D polylines

Annotation text

Non-AutoCAD formats:

ASCII point files

ASCII polyline files

3D Studio mesh files

Binary QSB and QSP surface and polygon files

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Introduction Page 3

Quicksurf surfaces

A surface, in Quicksurf terms, is a mathematical description of athree dimensional surface based on original point or break line

data. Surfaces are maintained in Surface memory, which is part

of AutoCAD controlled memory, separate from the drawing data-

base. Mathematically, a Quicksurf surface is a single-valued

function of the independent variables x and y. This means that no

part of a surface may be overhanging or exactly vertical, since it

would have more than one elevation (z value) at an x,y, point. A

surface may consist of any combination of each of the following

elements:

Points

Break lines (Breaks)

Triangulated irregular network (TIN)

Derivatives

Grid

Triangulated Grid (TGRD)

A new surface may be created with just Points as a result of load-

ing X,Y,Z triplets from an ASCII file or extracting points fromentities in the drawing with the Extract to surfacecommand.

Breaks may be incrementally added to a surface by extracting

polyline entities as break lines with Extract Breaks. The calcula-

tion of a surface model with the TIN, Grid, TGRD, or Contour

commands create the TIN, Derivatives, Grid or TGRD parts of

the surface as needed.

Quicksurf also has the ability to manage an unlimited number of

these surfaces (dependent on your machines resources) with each

having any combination of these elements. Multiple surfacesallow you to perform algebraic operations between surfaces

resulting in surfaces representing thicknesses, cut and fill vol-

umes, exaggerated surfaces, slopes and many other possibilities.

Quicksurf maintains one special surface which is called the

resultssurface or the dot surface. When you load data from

an ASCII file, or use the Extract to surfacecommand to extract

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Page 4 Introduction

X,Y,Z data from AutoCAD entities you create a new surface.

Any of these actions replace the pre-existing contents of the surface. You may save surfaces as namedsurfaces with the Sur-

face Operationscommands.

Quicksurf uses surface memory storage (rather than the

AutoCAD drawing database) to decrease the amount of memory

required to manipulate data, providing fast execution of modeling

operations. Fast and efficient operation in memory provides

instantaneous results allowing for thought and analysis to pre-

dominate your design process, rather than waiting for calcula-

tions.

A surface is stored in AutoCAD-controlled memory, but is not

part of the drawing until you instruct Quicksurf to add it to the

drawing by issuing a drawresponse to a Quicksurf command.

A surface will not be visible until you use the specific Quicksurf

commands which display surface geometry and their Drawor

Showoptions to display the surface in the current viewport. In

the interest of speed the Quicksurf commands of Points, Breaks,

TIN, GRD, Triangulated Grid(TGRD), Contourand Post from

Memorysupport the ability to either Showor Draw. Drawpro-

duces AutoCAD drawing entities (such as points, polylines or

polyface meshes) from a surface model, making them a perma-

nent part of the drawing, while Showtemporarily displays them

in the current viewport (until the next event causing a redraw, like

pan orzoom). Using Showallows you to maintain visibility of a

model throughout a series of surface operations or viewpoint

manipulations without waiting for regens or redraws; once a

model is completed it can be incorporated into the drawing withthe Drawoption of the appropriate command.

Using Showis substantially faster than Draw, but remember a

Shownobject is not an AutoCAD entity, so it cannot be selected

or manipulated with AutoCAD commands and will not be saved

with the drawing file when you save the drawing.

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Introduction Page 5

Surfaces in memory will not be saved with the drawing when an

AutoCAD Saveor Endcommand is executed, but you will begiven a chance to save surfaces when exiting the drawing. If you

need to save the contents of surface memory, Quicksurf provides

a separate command (Write QSB)that allows you to write one or

more surfaces from surface memory to disk independently of the

AutoCAD drawing. This provides more efficient use of storage

(as much as 50% less) and preserves all parts of a surface in a

quickly retrievable form.

Surface models

Starting from points and/or break line data, Quicksurf can gener-

ate the following basic model types:

Triangulated Irregular Networks (TIN)

Grids

Triangulated Grids (TGRD)

Contours may then be generated from the TIN, TGRD or Grid

surface model. Any AutoCAD entity may then be draped ontothe surface so it lies on or follows the surface exactly. In this way

you may turn 2D map data into 3D maps or solve for the surface

elevation at any point(s) by draping.

Break line data, representing 3D polylines where surface slopes

are discontinuous, may be used without limitation on number or

complexity. Both smooth surface curvature and break line slope

discontinuities may be combined in the TGRD surface model.P

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Page 6 Introduction

Surface estimation methods

TIN models are created using highly optimized Delauney triangu-lation which optimally connects all of the data points. TIN mod-

els linearly connect the control points with planar triangular

faces. Grid models provide surface estimation between control

points and may be created using several different methods includ-

ing:

Linear interpolation

Continuous curvature

Continuous slopeKriging

Linear

Exponential

Spherical

Gaussian

Piecewise continuous

Hole

Surface editingAny surface may be edited to change its shape to honor your

design or interpretation. The edited surface may then be used like

any other for volume, slope, or surface to surface computation.

Surface manipulation

Quicksurf can maintain multiple surfaces in memory simulta-

neously. Surface algebra may be performed between surfaces,

including addition, subtraction, multiplication, division, loga-rithms, relational comparisons, slope calculation and more. Two

simple examples of surface algebra are subtracting an existing

topography from a proposed topography to calculate a cut and fill

surface to be used in volume calculation, or subtracting the top of

a geologic horizon from the base of the same horizon to calculate

thickness.

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Introduction Page 7

Surface algebra and surface manipulation is performed within the

Surface Operationssubsystem of Quicksurf. Polynomial trendsurface analysis and automatic residual calculation are also avail-

able in Surface Operations.

Volumetrics

Fast, accurate volumes may be calculated on one thickness sur-

face, between two different surfaces or between a surface and a

constant. The volumes may be computed for the entire surface or

separately on one or more arbitrary sub-areas.

Construction tools

A broad suite of construction utilities are included to help with

your design process. Intersect slopeprojects a given slope up or

down from a 3D control line until it intersects the specified sur-

face, then draws a 3D polyline representing the intersection in

space. Daylight lines in site planning, fault traces in geology and

bench edges in mine design are determined painlessly.

Apply section applies a cross-section template of any complexity

to a 3D polyline path to automatically create all of the breaklines

for a roadway, including the daylight lines at the head of the cuts

and base of the fills. Points on the original topographic surface

are automatically moved to a different layer within the disturbed

design area.

3D Offsetoffsets a 3D polyline normal to itself and a user-speci-

fied horizontal and vertical distance.

Quicksurf is a not tailored to one specific discipline. We have

attempted to give you the fastest, most flexible surface modeler

available. As you use Quicksurf, you will find that there are

many different ways to accomplish the same end. In this manual

we strive to give you the background to quickly use Quicksurf

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Page 8 Introduction

productively. We cannot cover everything, so consider attending

one of the several Quicksurf courses offered by Schreiber Instru-ments to tune your skills and get the most out of your investment.

Using this manual

This manual is organized into several chapters on concepts, a

large command reference, and many specific application exam-

ples. Please take the time to read the concepts chapters. Quick-

surf is a big, powerful program and you really need to develop a

framework to understand and effectively use its capabilities. Thecommand reference chapter is the how-to chapter, stressing syn-

tax and command result, rather than concept or tutorial examples.

The application examples present small discipline-specific tutori-

als of common tasks. A short workflow summary is included in

each application example. They do not need to be done in any

given order, but some of the more complex ones do build on

skills covered in the simpler ones. For example, it will be worth

your while to do the simple building pad example before you

tackle building an entire road. The troubleshooting chapter sum-

marized common problems and their causes.

Typeface conventions

Several different typefaces are used within this manual:

Menu entry or Check box or Edit box

Prompt

User response to prompt

Button

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21/456System software requirements Page 9


System software requirements

Quicksurfis implemented for operation from AutoCAD Release

12 or 13 for DOS, Windows and 14 for Windows. The program

will not run on earlier releases of AutoCAD. Quicksurfis

designed to work seamlessly with other Schreiber products such

as Spatial Explorerand QuickSurf Proif present, but Quicksurf

has no additional requirements other than AutoCADs.

System hardware requirements

Quicksurfoperates within AutoCAD Release 12, 13, or 14 and

has no hardware requirements over and above those of AutoCAD

itself. If you plan to construct very large complicated models,

more memory will allow faster construction times. We suggest

the following basic system configuration as a minimum for effi-

cient operation:

80486 or Pentium processor

16 megabytes RAM (32MB for ACAD R13)

Sufficient free hard disk space to accommodate your model

VGA monitor or better

Required knowledge

Effective use of Quicksurfrequires a basic working knowledge ofAutoCAD. Familiarity with AutoCAD entity types (points,

polylines, polyface meshes, text and inserts) and basic use of

viewing commands (Pan, Zoom, etc.) is needed. If you plan to

produce hard copy output, knowledge of the Plot, Hide, Shade,

and Rendercommands is helpful. This knowledge may be

gained by attending an authorized Autodesk Training Center,

guidance from an experienced AutoCAD user, or manual study.

Quicksurfrequires no other specialized training or knowledge.

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Page 10 Quick installation

Quick installation

Experienced DOS or Windows users may follow these abbrevi-

ated instructions. Install Quicksurfby inserting the floppy, typing

B:INSTALL and answer the drive and directory prompts.

Include the install directory (\QS51) in the ACAD path environ-

mental variable if you are running AutoCAD R12 or R13 outside

of the Windows environment. If you are unsure about anything,

please follow the complete step by step installation instructions

below.

Installation

Quicksurfis released on three 1.44-megabyte, 3 1/2-inch disks or

on the Schreiber Instruments CD-ROM, with an automatic instal-

lation routine. It is similar to the installation program used for

Autodesk products, so most users should be familiar with its

operation. The installation program will prompt the user for the

AutoCAD version and the appropriate drive and directory names

for placement of the support files. The installation requires

approximately three megabytes of free hard disk space. Installa-tion procedures for DOS, Windows and UNIX are described sep-

arately below.

CD ROM installation

If you are installing from the CD-ROM please follow the instruc-

tions on the CD label.

DOS Installation

The installation program runs from a floppy disk drive, generallydrive A or drive B. The following procedures assume drive B: is

the installation drive.

Insert the Quicksurfdiskette into disk drive B: and close drive

door.

Type B:INSTALLat the DOS prompt and then press Enter.

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Installation Page 11

The installation program will prompt you for the required infor-

mation to complete the installation process. If you decide to quitbefore the installation is completed, press ESCto abort and return

to DOS. Please note that aborting the install process may leave

files on your hard disk. When you restart the installation, these

files will be automatically copied over (prompting you to allow

overwriting of the old files), unless a different drive-directory is

specified.

The installation routine first displays the software name and ver-

sion number being installed. It then displays the following

prompts:

Please choose one AutoCAD release for running Quicksurf:

The flashing selection

will be used.

The available AutoCAD releases are shown, with the potential

selection flashing. Use the up or down cursor (arrow) keys to

highlight your selection then press return to accept it. If more

than one AutoCAD releases are run on the same system, the

Quicksurf install program may be run a second time.

On which disk drive do you wish to install Quicksurf?

The available drive letters will be shown, with the potential selec-

tion flashing. Use the up or down cursor (arrow) keys to high-

light your selection then press return to accept it. Quicksurfmay

be installed on a network drive, but is only valid for one user at a

time unless additional licenses are obtained.

The next prompt is for a directory for placement of the Quicksurf

files.

Please specify the directory on your disk where Quicksurfshould be installed:\QS51

We highly recommend you accept the default directory name

offered. The path defaults to \QS51, but may be changed to cor-

respond to the directory of your choice. If you do choose to place

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Page 12 Installation

the files in a different place, be sure to alter your ACAD path

variable accordingly. After successful input to the these prompts,the hard disk installation process begins.

Unpacking executables...

The files will be copied to the drive and directories you chose.

The program and support files will then be expanded from their

compressed format.

There is a DOS environmental variable called ACADwhich tells

AutoCAD where to look for files it needs. You must add the\QS51directory to this AutoCAD path, so Quicksurf can be found

by AutoCAD. If you fail to do this you will receive an Unknown

commanderror message from AutoCAD when trying to access

Quicksurf commands.

The ACADpath variable needs to include the node for the direc-

tory in which you installed Quicksurf(such as "C:\QS51").

TheACADvariable is either set by a line in your AUTOEXEC.BAT

or in the batch file you execute when starting AutoCAD. For

example, a typical SET statement from your AUTOEXEC.BATor

ACADR12.BATwould look as follows:

Setting this variable

properly is critical!

SET ACAD=C:\QS51;C:\ACAD\SUPPORT;C:\ACAD\...

Remember that the maximum length of a SETstatement is 126

characters.

The most common installation problem occurs when AutoCAD is

started from a batch file which resets the ACADpath variable sub-sequent to the place where it is set originally (AUTOEXEC.BAT). If

you start AutoCAD from a batch file either directly (such as

ACADR12.BAT) or indirectly (such as selecting AutoCAD from a

menu), you must alter the SET ACAD= statement in the batch file

which starts AutoCAD.

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You can confirm the setting of the ACADvariable as seen by

AutoCAD by starting AutoCAD, then shelling out to DOS (typeShellfollowed by two returns), then typing SETat the DOS

prompt. This lists the environmental variables including the

ACADpath variable. If C:\QS51; is not in the "ACAD=" line, then

you have not correctly set the ACADvariable and Quicksurfwill

not run. Fix it before proceeding.

Installation is now complete.

Convertible demonstration software

Quicksurfis shipped either as a hardware-keyed convertible

demo or as an unprotected licensed version upon purchase. In

demo mode without a hardware key, Quicksurfonly works with

the included sample data set and will not import your data. With

a Schreiber hardware key installed in a parallel port, this demo

version is the same as the full unprotected Quicksurf software.

All Quicksurf copies outside of the United States and Canada are

required to be hardware locked versions.

Unprotected softwareFully licensed Quicksurf users in the United States or Canada are

shipped unprotected copies of Quicksurf, with the understanding

that each Quicksurf license is for one concurrent user. Two

simultaneous users require two licenses. Additional licenses are

available at significant discounts, contact Schreiber Instruments

or your dealer for information.

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Windows Installation

All versions of Quicksurf should be installed from the main DOSprompt (such as C:>), not from inside of Windows or a DOS win-

dow. The installation program runs from a floppy disk drive,

generally drive A or drive B. The following procedures assume

drive B: is the installation drive.

Insert the Quicksurfdiskette into disk drive B: and close drive

door.

TypeB:INSTALL

at the DOS prompt and then press Enter.

The installation program will prompt you for the required infor-

mation to complete the installation process. If you decide to quit

before the installation is completed, press ESCto abort and return

to DOS. Please note that aborting the install process may leave

files on your hard disk. When you restart the installation, these

files will be automatically copied over (prompting you to allow

overwriting of the old files), unless a different drive-directory is

specified.

The installation routine first displays the software name and ver-

sion number being installed. It then displays the following

prompts:

Please choose one AutoCAD release for running Quicksurf:

The flashing selection

will be used.

The available AutoCAD releases are shown, with the potential

selection flashing. Use the up or down cursor (arrow) keys to

highlight your selection then press return to accept it. If more

than one AutoCAD releases are run on the same system, theQuicksurf install program may be run a second time.

On which disk drive do you wish to install Quicksurf?

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The available drive letters will be shown, with the potential selec-

tion flashing. Use the up or down cursor (arrow) keys to high-light your selection then press return to accept it. Quicksurfmay

be installed on a network drive, but is only valid for one user at a

time unless additional licenses are obtained.

The next prompt is for a directory for placement of the Quicksurf

executable files.

Please specify the directories where the Quicksurfexecutables should be installed:

The default will be \ACADWIN for AutoCAD Release 12 or

\ACADR13\WIN for AutoCAD Release 13. The Quicksurf exe-

cutable files should be placed in the same directory with the

AutoCAD executables.

Please specify the directories where the Quicksurfsupport files should be installed:

The default will be \ACADWIN\SUPPORT for AutoCAD

Release 12 or \ACADR13\WIN\SUPPORT for AutoCAD

Release 13. This directory is where the menus and associated

files are placed.

Please specify the directory where the sample filesshould be installed: \QS51

We recommend you accept the default directory name offered.

The path defaults to \QS51, but may be changed to correspond to

the directory of your choice. The example files will be placed inthe directory you specified here.

After successful input to the these prompts, the hard disk installa-

tion process begins.

Unpacking executables...

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The files will be copied to the drive you chose. The program and

support files will then be expanded from their compressed for-mat.

A de-installation routine (RMQS51.BAT) is included which will

delete all Quicksurfprogram files from this directory.

If you have performed a custom installation and placed the

Quicksurf program files in a different directory than the sug-

gested directories, you must alter the ACAD environmental vari-

able to include the node for the directory in which you installed

Quicksurf executable files. This need not be done for a standard

installation.

When finished, the install program will report:

Quicksurf has been successfully installed.

Convertible demonstration software

Quicksurfis shipped either as a hardware-keyed convertible

demo or as an unprotected licensed version upon purchase. Indemo mode without a hardware key, Quicksurfonly works with

the included sample data set and will not import your data. With

a Schreiber hardware key installed in a parallel port, this demo

version is the same as the full unprotected Quicksurf software.

All Quicksurf copies outside of the United States and Canada are

required to be hardware locked versions.

Unprotected software

Fully licensed Quicksurf users in the United States or Canada areshipped unprotected copies of Quicksurf, with the understanding

that each Quicksurf license is for one concurrent user. Two

simultaneous users require two licenses. Additional licenses are

available at significant discounts, contact Schreiber Instruments

or your dealer for information.

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Hardware keys Page 17

Hardware keysFor international and OEM systems, Schreiber Instruments pro-

vides a hardware key. Customers with hardware keys simply

plug the key into parallel port 1 or 2 and plug the printer into the

key. If you are using hardware keys with a printer plugged in, we

recommend that the printer be turned on.

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Page 18 Network considerations

Network considerations

The Quicksurf program and support files may be installed on a

network drive. As long as the directories containing these files

are available on the ACAD path, Quicksurf will function nor-

mally. For hardware locked versions, Quicksurf will be in demo

modeif accessed by nodes without a hardware key present. A

network hardware key for multiple users is being developed for

OEM and international use. Contact Schreiber Instruments tech-

nical support department for more information.

Please note: On AutoCAD R14 installations on a network serverthat does not support long filenames you will have to make modi-

fications to program filenames for proper operation.

Network installations require either multi-seat licenses or a site

license. A single Quicksurf license is for one concurrent user and

additional seats require additional licenses. Multi-seat licenses

are available at significant discounts from the single seat price.

Please contact Schreiber Instruments or your Quicksurf dealer for

further information.

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Customer support Page 19

Customer support

Schreiber Instruments, Inc. provides several mechanisms for

technical support.

TELEPHONE (303) 843-9400 8:00 TO 5:00 MST MON-FRI

FACSIMILE (303) 843-9885 24 HRS.

World Wide Web (WWW) http://www.schreiber.com/ 24 HRS.

Schreiber technical support is provided as a service for our cli-

ents. Free technical support is available free via our WWW site.

Our toll-free 800 telephone lines go to our sales department andno technical support is available on them.

Free technical support is available via WWW or FAX for all

Schreiber products. We endeavor to keep the WWW Tech Sup-

port current, informative and containing the latest examples of

techniques to help you.

Free voice technical support is available for the first 60 days after

purchasing any Schreiber product. After 60 days, free technical

support is still available via our WWW or via fax. Voice techni-cal support after the first 60 days is available by purchasing a

technical support contract. Questions on installation will be

accepted on voice lines and answered immediately at no charge,

regardless of whether the 60 day period has elapsed.

Schreiber Instruments, Inc. does not provide technical support for

AutoCAD onlyfor Quicksurf. If you have a question related to

an AutoCAD function or configuration, or hard copy plotting

please call your AutoCAD dealer for technical support.

Include the following on any tech support request:

1. Product name ( i.e. Quicksurf) and version number (Use the

Versionselection on the configuration menu of the Quicksurf

menu)

2. If the problem can be represented visually, plot the problem

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Page 20 Customer support

or use the Saveimgcommand to make a GIF file and utilize

email to send your image or data file to [email protected] can often answer your question in much less time if we

have a picture of your problem. Alternatively you may fax us

an image.

3. Certain complex problems may require us to see the data set.

In such cases, utilize our bulletin board system to upload your

Quicksurf configuration file (.qcf) and AutoCAD drawing

file (.dwg) so we can try to duplicate the behavior. Please

remove any unnecessary objects from the files to keep the file

size as small as possible. Email your files zipped [email protected] and technical support will respond back

in 1 to 2 business days.

4. Have your question well formulated and written down so that

all questions may be answered in one pass.

We look forward to answering your questions about Quicksurf.

We will endeavor to answer your questions in a timely fashion.

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33/456Whats a surface? Page 21

Chapter 3: Concepts

Whats a surface?

Quicksurf creates and manipulates surfaces. A Quicksurf surface

is the mathematical description of a surface which exactly honors

all input data points. Quicksurf surfaces are a single-valued func-

tion of independent variables X and Y. This means that a surface

only has one Z value for any given (X, Y), and so does not model

overhanging surfaces or exactly vertical surfaces.

Surface may represent anything. Existing topography, proposed

topography, thickness maps, geologic structure maps, concentra-

tion distribution, slope maps, pressure gradient maps may all be

represented as Quicksurf surfaces. Surfaces may intersect.

Overhanging surfaces may be modeled in multiple patches.

Quicksurf has no limit on the number of points in a surface or the

number of surfaces simultaneously used. The ultimate limitation

is available space on your hard disk drive.

Surfaces contain one or more parts such as points, break lines,

triangulated irregular networks (TIN), grids or triangulated grids

(TGRD).

A surface is not an AutoCAD drawing entity, rather it is a mathe-

matical description held in surface memory. Representations of a

surface, such as points, contours, grids or TINs may be drawn

into your AutoCAD drawing as point, line, polyline, 3D face,

polyface mesh or mesh entities. It is important to keep the dis-tinction between Quicksurf surfaces (which reside in surface

memory) and drawn AutoCAD entities representing parts of sur-

faces (which reside in the AutoCAD drawing database).

All drawing entities created by Quicksurf are placed in their

proper position in 3D model space.

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Chapter 3: Concepts

Page 22 Whats a surface?

Surface memory

Quicksurf creates a unique unit of memory storage insideAutoCAD-controlled memory commonly referred to as a surface.

Surface memory has the ability to manage an unlimited number

of these surfaces (dependent on your machines resources). Mul-

tiple surfaces allow you to perform algebraic operations between

different surfaces, resulting in surfaces representing thicknesses,

cut and fill volumes, exaggerated surfaces, surfaces representing

slopes and many other possibilities.

Quicksurf uses surface memory, rather than the AutoCAD draw-ing database, to store and manipulate surfaces. Although surfaces

are stored in AutoCAD-controlled memory, a surface is not part

of the drawing until you instruct Quicksurf to add it to the draw-

ing by issuing a Drawresponse to a Quicksurf command such as

Contour.

Surface memory versus the AutoCAD drawing

PointsBreaks

TINDerivativesGridTriangulated grid

PointsLines

2D polylines3D polylines3D facesPolyface meshesPolygon meshes

ASCII point filesASCII break filesQuicksurf QSB filesDEM data files

Surface Memory AutoCAD Drawing

Disk Files

Draw

Extract

Read

Write

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Chapter 3: Concepts

Whats a surface? Page 23

A surface will not be visible until you use specific display com-

mands (Points, Breaks, Contour, TIN, Grid, Triangulated grid)andtheir Drawor Showoptions to either draw or temporarily display

the surface in the current viewport. The Showoption temporarily

displays the requested contours or surface element on your draw-

ing screen, until the next AutoCAD Redraw. The Drawoption

adds the requested contours or surface element to the drawing

database as AutoCAD entities.

Quicksurf maintains one special surface which is the resultssur-

face named dot. When you load point data into surface

memory it is placed into the surface. The results of any sur-face operation are placed in the surface. Any of these actions

replace the pre-existing contents of the surface. You may

make copies of any surfaces or rename surfaces using the surface

management commands within Surface Operations.

Surfaces in memory will not be saved when an AutoCAD Saveor

Endcommand is executed. Quicksurf instead provides a separate

command (Write QSB)that allows the user to write a one or more

surfaces to disk independently of the AutoCAD drawing. This

provides more efficient use of storage (as much as 50% less) and

preserves all parts of a surface in a quickly retrievable form. If

you attempt to exit AutoCAD with surfaces still in memory, you

will receive an alert and be offered the chance to save them.

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Chapter 3: Concepts

Page 24 Parts of a Surface

Parts of a Surface

The component parts of Quicksurf surfaces can be divided into

data parts, which you supply, and calculated parts, which Quick-

surf calculates. The following discussion of surface parts relates

to the characteristics of the surface parts, not the methods used to

create them. Realize that the elevations of calculated parts, such

as a grid or triangulated grid, may be computed using different

algorithms.

Basic parts of a surface

Points

TIN

Grid

Contoursare not a surfacepart, rather a resultof interpolating on a

TIN, Grid or TGRD

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Chapter 3: Concepts

Parts of a Surface Page 25

Data parts

The two types of data Quicksurf uses to create surface modelsconsist of points and/or break lines.

Points

Points form the basis of most surfaces. Points are unique X,Y,Z

triplets in AutoCADs World Coordinate System. Point data may

be loaded to surface memory by the following commands:

Extract to Surface (QSX)

Merge Extract (QSMX)Read ASCII Points (QSL)Read ASCII Table (QSML)

Read QSB FileRead DEM File

Load Points (with optional Geokit)

The Extractcommands extract point data from AutoCAD draw-

ing entities. The Readcommands read point data from disk files.

The Load Pointscommand reads point data directly from data-

base files.

Breaks

Break line data (Breaks) are 3D polylines which represent abrupt

discontinuities in the slope of a surface. Examples of breaks are

the edges of ditches, walls and curbs in civil engineering and

faults in geology. Whereas a surface without breaks maintains

continuous slope and curvature throughout, a surface with breaks

may have abrupt changes in slope at the trace where the surface

crosses break lines.

Break line data may be loaded to surface memory by the follow-

ing commands:

Extract Breaks (QSBX)Read ASCII Breaks (QSBL)

Read QSB File

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Chapter 3: Concepts


The Extract Breakscommand extracts break data from AutoCAD

drawing entities such as 2D and 3D polylines. Read ASCIIBreaksreads break data from disk files, such as survey data.

Read QSBreads break data from Quicksurf surfaces previously

stored to disk.

Calculated parts

The calculated parts of a surface are the Triangulated Irregular

Network (TIN), Derivatives, Grid and Triangulated Grid

(TGRD). Some Quicksurf commands calculate more than one ofthese parts.

Command Parts calculated

TIN TIN

Grid TIN, Derivatives, Grid, as necessary

TGRD TIN, Derivatives, TGRD as necessary

Contour TIN, Derivatives, Grid, TGRD as necessary

Triangulated irregular network (TIN)

The triangulated irregular network, or TIN, is a three-dimensional

model of a surface composed of planar triangular faces. Quick-

surf generates it based on the Delauney criterion, by which points

are connected optimally to make all triangles as nearly equilateral

as possible. The TIN may be used directly for volumetrics, pro-

files, elevation analysis, contouring or as a surface to render.

Since each vertex of the TIN is a surface point, a TIN honors allthe points exactly.

Quicksurf also uses the TIN to identify neighboring points when

calculating derivatives for gridded surfaces. Quicksurf can draw

the TIN as lines, 3D faces or polyface mesh entities.

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Chapter 3: Concepts


Derivatives

When Quicksurf generates a surface where surface curvature iscalculated, slope information (1st and 2nd derivatives) are calcu-

lated at each vertex of the TIN, representing the slope of the sur-

face at that vertex. The derivative order, weighting and blending

The 1st derivativesof a

surface represent slope.

parameters affecting this calculation are set within the Configure

Griddialog.

The 2nd derivativesof

a surface represent

curvature.

Whether or not surface curvature is calculated between control

points is based on the Derivativesetting in the Configure Grid

dialog box. When surface curvature is requested, the derivativesare used to fit a smoothly curved polynomial surface to each tri-

angular face of the TIN. By default this polynomial surface has

continuous slope and curvature between all neighboring faces of

the TIN, except at break lines, where the slopes are allowed to be

different on either side of the break line. If a TIN is created from

a data set including break lines, the break line information is

totally represented in the resulting TIN and derivatives. The TIN,

along with derivatives, represent the complete mathematical sur-

face description. Both the GridandTGRDcommands use these

to solve for elevation at each grid node during surface construc-tion.

Surface curvature

TIN withoutcurvature

Grid withcurvature

Input

data

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Chapter 3: Concepts


Grid

The grid consists a set of vertices, spaced rectangularly in the Xand Y axes, with Z values conforming to the modeled surface.

Although the mathematical model used honors the input data

exactly, the resultant grid model is comprised of cells with verti-

ces that are not members of the input point data set. Therefore,

the final grid model will very nearly honor the input data set, but

may not match the data set exactly. As a smaller grid cell size is

used, any error between the input data set and the calculated grid

is reduced. As a larger grid cell size is used, the potential error

between the input data set and the calculated grid increases. Thegrid model provides for a smoother representation of the data,

when contoured, than a TIN due to the larger number of vertices

present for contour interpolation.

Gridding is very effective when dealing with data sets that do not

contain break data. The grid does not have the capacity to truly

represent break line data due to the fact that the cells have consis-

tent spacing, causing the breaks to be smoothed to the grid cell

size.

Data sets which contain break lines should be modeled witheither a TIN or TGRD, rather than a grid.


The Triangulated Grid (TGRD) model combines the best parts of

the TIN and grid models into one continuous model of a surface.

The TGRD is used for surfaces which contain both points and

break line data, and produces a smooth curved surface away from

break lines, but honors break lines exactly.

A Triangulated Grid consists of point data and densified 3D

breakline data which have been internally gridded based on the

derivative and cell size settings of Configure Grid. The resulting

grid node data, along with the breakline data, form a point set

which is triangulated to form a special TIN termed a Triangulated

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Chapter 3: Concepts


Grid (TGRD). This TGRD is a TIN which honors breakline data

exactly, but also may honor curvature data when away frombreaklines.


A TGRD surface honors breaklines exactly, with each break line

represented as edge of a triangle. Away from break lines, the ver-

tices of a TGRD triangles are coincident with where regular grid

nodes would have been. The original data points are no longer

vertices of the TGRD. The TGRD model produced has smoothgrid characteristics (two triangles per grid cell) when away from

break lines and behaves as a normal TIN near break lines.

To create the diagram above, first the control points on the sur-

face were extracted, then the three 3D polylines representing the

edges and bottom of the ditch were extracted as break lines. A

triangulated grid was then built with the TGRD command.

The Triangulated Grid may be used for volumetrics, profiles, ele-

vation analysis, and contouring. Since each vertex of the TGRD

is a surface point, it honors all of the grid nodes and breaks line

vertices exactly. Quicksurf can draw the TGRD as lines, 3D faces

or polyface mesh entities.

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Break lines

A break line is a 3D polyline which lies in the surface alongwhich the slope of the modeled surface is allowed to change

abruptly. This enables modeling such features as roads, excava-

tions, retaining walls, normal faults and structures.

Under ordinary gridding conditions, Quicksurf will calculate first

and second derivatives at all control points based on the elevation

values of these points and their neighboring points. These are

used in the polynomial equations that will be solved for the z val-

ues at the grid vertices. The resulting grid will have continuousslope and curvature (i.e., first and second derivatives) everywhere

on the modeled surface. Data near an abrupt slope change will not

be honored exactly because of smoothing errors associated with

gridding. If we designate the abrupt slope change as a break line,

the surface is calculated differently to honor the slope change.

When a break line is encountered by TGRD, both slope and cur-

vature are allowed to be different on either side of the break line.

When a grid is generated, the break line will form the intersection

of two surfaces of different slope and curvature: i.e., an edge.There will be no smoothing errors and elevation data will be hon-

ored exactly.

The figures which follow illustrate the effect of adding break

lines with the Extract Breakscommand on a surface having a V-

shaped excavation. A standard grid of the original topography is

shown along with the TIN of the original control points. The

standard gridded surface (top figure) was generated by extracting

the original spot elevations with the Extract to Surfacecommand.

This grid shows a rolling surface created by the smoothing pro-cess inherent in gridding with continuous curvature selected.

Several 3D polylines representing the edges and bottom of a pro-

posed ditch are shown. Extracting these 3D polylines as break

lines with the Extract Breakscommand produces a TIN, but with

no curvature away from the break lines (bottom figure).

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Chapter 3: Concepts


Grid of original topography

TIN of original seven points

TIN after ditch break line extraction

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Chapter 3: Concepts


Subsequently using the TGRD command produces the accurate

reproduction as the triangulated grid. The TGRD surface is a TINwhich honors both the grid nodes and break lines exactly.

A TGRD gives the best representation

Grids should not be used with surfaces containing break lines. A

grid will average across break line and tend to smooth across the

breaks. The figure below shows a grid for this same data set.

Gridding does not honor break line exactly

Breaks may be established by any AutoCAD drawing entity, but

2D and 3D polylines are most efficient. Remember that the break

line must follow the elevation of the surface to produce meaning-

ful results.

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Chapter 3: Concepts


There are two special considerations in break line modeling: ver-

tical discontinuities and intersecting breaks.

Vertical discontinuities

Recall that the Quicksurf definition of a surface is a single-valued

function of the independent variables X,Y. This means that no

part of a surface may be exactly vertical, since it would have

more than one elevation value at a given X,Y point.

However, the steepest surface Quicksurf can model is one in

which the upper and lower edges are displaced by approximatelydrawing units, which is indistinguishable from vertical in

most cases. The applications chapter on wall construction dis-

cusses methods for approximating vertical surfaces.

Intersecting break lines

Quicksurf densifies all break lines and resolves all crossing break

lines during break extraction. When Quicksurf processes a single

break line, the elevation of the break line itself furnishes the ele-vation of all densified surface points along it. This produces a

potential ambiguity when two break lines intersect over a com-

mon X,Y point, yet differ in elevation. Intersecting break lines

are representing the same surface, therefore the elevation must be

the same at any break line intersection. Quicksurf resolves this by

setting the elevation of the surface to the mean of the elevation

values on the two break lines. This feature resolves small mea-

surement and interpolation errors.

To resolve crossing break lines, Quicksurf must compare everysegment of every break line against every other segment. As the

number of break lines increases, the computation time increases

dramatically.

Stacked data points (multiple control points at a given X,Y loca-

tion) along break lines are dropped. Quicksurf resolves stacked

data by arbitrarily deleting points from a stack until there is only

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Chapter 3: Concepts


one. Break lines made up of multiple polylines joined with com-

mon endpoints must be treated as break line intersections, whichtherefore slows processing.

Contours

Contours are 2D polylines that follow paths of constant elevation

on the modeled surface. Contouring is the interpolation of a spec-

ified Z value on a TIN, TGRD or Grid model. Although contours

are produced from a surface model, they are not inherently part of

the surface model. Contours are always generated on the fly fromthe surface model of the users choice (Configure Contour).

Grid based contours TIN based contours

Contouring from a TIN or TGRD is done via basic linear interpo-

lation which interprets each face of a triangle as a plane in space.

Contouring from a Grid is done by linear interpolation on the grid

cells. This interpolation is performed by solving polynomial

equations representing each triangle of the TIN for a constant Z

value. In the illustration above, the same area was contoured onthe Grid and the TIN. You can see the TIN edge effects on the

TIN based contours.

The segment of a contour line within onetriangle or grid cell is

always a straight line. Grid cell size therefore has a profound

effect on the smoothness or angularity of contours.

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Chapter 3: Concepts

Grid Methods Page 35

Grid Methods

A grid may be calculated by many methods within Quicksurf.

Each of these methods has several options providing for numer-

ous gridding methods.

Continuous Curvature (Standard method)

The Standard method calculates polynomial equations for each

individual face of a TIN and evaluates the polynomials at grid

vertices that fall under the TIN faces. The user may set the deriv-

atives calculated for each triangle to None, 1stor 2ndin the Con-figure Griddialog.

The results are quite different: Using derivatives set to None

results in a grid fitted to the TIN in planar fashion. This method

involves no polynomial generation. Grid vertices are simply

interpolated against the planar TIN faces. Using 2ndderivatives

produces a smoothed surface with continuous slope and curva-

ture. This method occasionally may produce surface overshoot

problems in areas of very rapid slope changes, but provides

excellent results on most data sets.

These continuous curvature methods are the fastest available and

provide excellent results when large data sets are to be modeled.

Trend surfaces

The Trend method of gridding allows you to select a particular

order polynomial surface and fit it to the entire data set using a

least squares fit. You may choose the highest cumulative order ofthe polynomial in all directions, or specify the order in X and Y

directions independently to yield a polynomial with more terms.

The selection of a Type 1, first order trend will result only in a

least squares fit of a planar surface to the data set. This can be

very useful when generating uniformly sloping surfaces to subse-

quently drape entities onto. Trend surface and trend surface resid-

ual generation are also available as surface operations.

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Chapter 3: Concepts

Page 36 Grid Methods

Kriging

Kriging is a geostatistical approach to surface generation. Krigingallows the user to design and apply specialized functions to pre-

dict the variance the Z value of a surface as a function of distance

between control points. The use of kriging requires understanding

of semi-variograms and their relationship to spatial distribution of

data. When applied without a working knowledge of this theory

it is liable to produce inaccurate or deceptive results.

Quicksurf includes interactive semi-variogram design using the

Variocommand and supports linear, piecewise, spherical, gauss-ian and hole semi-variograms. The kriging tools of Quicksurf are

supplied for users already familiar with kriging techniques. This

manual does not cover theory related to kriging. Kriging is useful

in such disciplines as geophysics, environmental studies, and

remediation projects. Users with small contaminant data sets

should consider using kriging rather than the standard continuous

curvature method.

Grids generated by any

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