The following text is from the Spatial Explorer manual, but this being only
a text file, all of the illustrations have been stripped out.  This means that
you will find references to non-existant illustrations, but you are a
sophisticated user, snooping around to find this anyway, so you'll be OK. 
The following text walks you through the sample data set included with the
program.  All of the commands will work with this data set, but you will not
be allowed to load your own data while in demo mode.  You may order the full
demo package for only $15. which includes the 150 page manual and illustrated
tutorials.  Either version may be converted to a full working version via
telephone to Schreiber Instruments at (800) 252-1024. 8-5 Mountain Time. 
Spatial Explorer costs $495. and requires AutoCAD Release 12. Both DOS and
Windows versions are available, but they are different, so be sure you load
the right one.

Loading the Spatial Explorer menu 

A DEMO.DWG file is supplied which uses this menu.  Otherwise 
type MENU from the AutoCAD command prompt and select 
SPE.MNU from the menu selection dialog box.  DOS users may 
need to change directories within the menu dialog to the \SPE1 
directory.  This is done by double clicking on the \ at the top of 
the left column, then double clicking on the SPE1 directory in the 
left column.  The SPE.MNU menu should then be selected from 
the list on the right side of the dialog box.  This loads the Spatial 
Explorer menu.

Loading the sample data set

Select the Explorer menu selection from the CONSTRUCT pull-
down.  This loads Spatial Explorer, if not loaded, and displays the 
main Explorer menu. If you get an unknown command error, you
have not set the ACAD variable correctly. 

Setup > Define Intervals

The Define Intervals dialog box is the basis for all interval and 
surface definitions.

Loading the surfaces

Select the Load QSB button to display the available Quicksurf 
binary surface files.  The standard AutoCAD file dialog box will 
be displayed.

Load QSB file dialog

The file dialog displays a list of the QSB files in the specified 
directory.  If you are not in the Spatial Explorer directory (\SPE1 
by default), use the left side of the file dialog to get there.  Select 
the DEMO filename from the right side of the dialog box. This 
will load surfaces from a file named DEMO.QSB and echo the 
number of surfaces in the file.  Your file list may only have one 
QSB file in it.  If Spatial Explorer is in demo mode this will be 
the only file you are allowed to load.

Defining intervals

Interval Properties

Next we will define intervals which will be used for all cross-sec-
tion and 3D wellbore construction.   This uses the Define Interval 
dialog box.

We will select the top and bottom surfaces and the desired layer, 
color and hatch patterns for each interval then put it into the Inter-
val Definition List by clicking on the Accept button. We will be 
using the upper right part of the Define Intervals dialog box.

Let's define three intervals from the surfaces we have loaded 
using the interval properties part of the Define Intervals dialog 
box.

First pull down the Top: list by putting the cursor on the Top: list 
button, then pressing the pick button.  A list pops down contain-
ing all of the surfaces currently loaded.  The first interval we want 
to define is from LIMESTONE to SHALE, so place the cursor on 
LIMESTONE and press the pick button.  LIMESTONE will 
appear in the Top: surface box.

Next click on the Bottom: button to pull down the surface list and 
pick SHALE.  SHALE will appear in the Bottom: surface box.

We now have the option of specifying the layer, color and hatch 
properties of the interval.

Picking the Layer: box pulls down a list containing all of the cur-
rently defined layers in the drawing.  Choose the layer name on 
which to place the interval you are defining. You may choose a 
named layer, or "Current layer" if you want the fence placed on 
the current layer at execution time.  If you want to draw it on a 
layer that has not yet been created, choose "Create layer" and then 
specify the name of a layer to be created during fence construc-
tion.  For this tutorial, let's choose "Create layer" and type SHAL-
LOW in the edit box which pops up.  Pick OK on the edit box to 
return to the main Define Intervals dialog.

Next click on the Color: button which brings up the standard 
AutoCAD color selection dialog.  Choose cyan, then click on 
OK.  You may pick a color with the mouse, or type a color name 
or number into the edit box at the bottom of the color selection 
dialog box.

Lastly, click on the Hatch: button to bring up the hatch selection 
dialog.  Verify that the Stored Hatch Pattern radio button is 
selected.  Pick the Pattern button to bring up the standard 
AutoCAD hatch selections as defined in standard acad.pat file.  
You may page through the hatch patterns, using the NEXT and 
PREVIOUS buttons.  Press the NEXT button to get to the page 
with the BRICK pattern and select it by clicking on the BRICK 
pattern (not the word BRICK).  This fills in the edit box to the 
right of the Pattern button with the selected pattern "BRICK".  In 
the Scale section of this dialog box be sure that "Auto" is 
selected.  Press OK to accept your hatch settings.

The hatch options correspond to and behave exactly as 
AutoCAD's.  Refer to your AutoCAD manual for specifics of 
hatch scale, rotation angle, and user-defined hatch options.  In 
general, avoid those hatch patterns which are not to scale (indi-
cated by an asterisk in the hatch selection dialog) as these are not 
compatible with Spatial Explorer's automatic scaling.

You have now set all of the interval properties: top surface, bot-
tom surface, layer, color and hatch pattern in the upper right por-
tion of the dialog box.  These interval properties are now  
accepted and placed into the interval definition list by clicking on 
the ACCEPT button.  Do this now.  You must press the ACCEPT 
button to define the interval by putting its definition into the 
defined intervals list.  After pressing the ACCEPT button you 
may alter one or more interval properties then press ACCEPT 
again to create a new interval definition.  Each time ACCEPT is 
pressed, an new interval definition is added to the defined inter-
vals list.

Your interval list should now contain one entry with a top of 
LIMESTONE, a bottom of SHALE, a layer of SHALLOW, a 
color of CYAN and a hatch of BRICK.

For each additional interval, select the properties (top, bottom, 
layer, color, hatch) then press the ACCEPT button to put them 
into the defined intervals list.  Add one more interval from a top 
of SHALE to a bottom of UNCONFORMITY, creating a new 
layer named MIDDLE, in color RED, with a hatch pattern of 
DASH.  Remember to press the ACCEPT button when through.  
When you are done the defined intervals list should contain two 
entries, one for each interval you have defined. The defined inter-
vals and their properties will remain defined until the end of the 
AutoCAD session unless redefined.  These interval definitions 
will control all subsequent 2D and 3D cross-sections and 3D 
wellbores.

Editing an interval definition

An interval definition may be edited by selecting one definition 
by clicking on it in the interval definition list (the selected entry is 
highlighted) and then picking the Edit Selected button.  This sets 
all of the interval properties in the upper right interval properties 
box to the values of the selected definition, then deletes the defi-
nition.  You may change any of the interval properties, then press 
ACCEPT to add the revised definition back to the interval defini-
tion list.  If you decide not to change anything after pressing the 
Edit Selected button, press the ACCEPT button to add it back to 
the interval definition list unchanged.

Let's change the layer name we specified for the SHALE-
UNCONFORMITY interval to the current layer rather than MID-
DLE.  Definitions may be selected or deselected by clicking on 
them with the mouse.  With just the SHALE-UNCONFORMITY 
layer highlighted, pick the Edit Selected button.  The Interval 
Properties box will be set to reflect the settings of SHALE, 
UNCONFORMITY, MIDDLE, RED, and DASH, and then the 
definition is deleted.  Select the Layer popup list and select "Cur-
rent".  Now click on the ACCEPT button to add the revised defi-
nition to the list.

Deleting an interval definition

Interval definitions may be deleted by selecting one or more by 
clicking on them with the mouse then clicking on the Delete 
Selected button.  The Delete All button deletes all interval defini-
tions.

Saving a setup

You may optionally save all of your current settings including 
intervals, their properties, file and path names for the data files, 
and all of your option settings to a setup file on disk.  This may be 
used for subsequent sessions so you don't need to re-enter interval 
definitions.  You may use saved setups as a style guide to help 
you create consistent displays across similar data sets.

To save a setup, click on the Save Setup button.  A file dialog box 
will appear and prompt you to specify a file name (no extension) 
for your setup file.  Spatial Explorer will write the file to disk and 
append the file type .SPE to the name you supplied.  Your file 
name must be a legal DOS filename with no extension.  Saving a 
setup file with the same name of an existing one overwrites the 
earlier one without comment.  This setup may then be recalled at 
any time with the Load Setup button.

Loading a setup file

Let's load a setup file with lots of interval definitions.  First click 
on the Delete All button to delete our practice interval defini-
tions.  Now click on the "Load QSB" button, select the DEMO 
QSB file, then press OK.  Click on the Load Setup button, select 
the DEMO setup file, then click on OK.  If the DEMO file does 
not appear on either list, change the path to the directory in which 
you installed Spatial Explorer (\SPE1) using the left side of the 
file dialog box.  A list of intervals will appear which we will use 
to investigate the capabilities of Spatial Explorer.

Now press OK to exit the Define Intervals dialog box.

Spatial Explorer saves memory by not retaining surfaces which 
were loaded but not used.  When you pressed OK and exited, only 
the surfaces involved in the defined intervals above were 
retained.  If you subsequently need to use surfaces which weren't 
retained, simply reload the surfaces using the Load QSB or Load 
ASCII buttons of the Define Intervals dialog box.

Building a 2D Cross-section

A 2D cross-section is built by drawing "lines of section" consist-
ing of polylines overlying your defined surfaces, then using the 
2D Sections command to show or draw the 2D cross-sections.  
We have already done the first step by defining the desired inter-
vals and their properties.

This section assumes you are doing the tutorial in order and have 
the Demo dataset and the Demo setup file loaded.  If you do not 
have the dataset loaded, load it now.

The next step is to be sure that the lines of section overlie the sur-
faces you wish to section.  If you are not in plan view, change to 
plan view.  From the Explorer pull-down menu, select the Show 
TIN command.  A list of surfaces will be presented in a dialog 
box.  Select any surface name (try LIMESTONE), then click on 
OK and the current viewport will be zoomed to overlie the sur-
face and the TIN (Triangulated Irregular Network) will be shown 
temporarily.  The TIN is the network of triangles which intercon-
nect your control points.  Every vertex represents a control point 
of your data set.  Because the TIN is SHOWn, not drawn, it will 
disappear the next time the screen is redrawn (by REGEN, 
REDRAW, PAN, ZOOM, VPOINT, etc.).

The previous figure shows the TIN as lighter lines.  Use the 
PLINE command to draw a polyline as shown.  The exact posi-
tion is not critical, but the first vertex of the line of section repre-
sents the LEFT end of the 2D cross section.  A Swap ends 
command is supplied to reverse vertex order if a line has been 
drawn in the wrong direction.

Type REDRAW, followed by a return to eliminate the shown 
TIN.

Pull down the Explorer menu and select the 2D Browse com-
mand.  This allows you to temporarily display a 2D cross-section 
interactively.  Select the polyline you just drew.    Selection may 
be made with any of the standard AutoCAD selection methods 
such as window, crossing, etc. or by answering "L" to use the last 
entity drawn.  Next you are prompted for a window in which to 
show the section.  Specify the lower left and upper right corners 
with the mouse and the 2D section will be automatically scaled to 
fit and will be displayed. 
Type REDRAW to clear the screen.  The 2D Browse command 
only shows a temporary section until the next redraw, so nothing 
is actually added to the drawing.

Use AutoCAD's ARRAY command to build twelve lines of sec-
tion as follows:

Array

Select objects: select the line of section

Rectangular or Polar array R/P <R>: R
Number of rows (---)<1>: 12
Number of columns (|||)<1>: 1
Distance between Rows: 500

This should array your line of section into a dozen equally spaced 
lines

Experiment with the Browse command selecting one line at a 
time.  The sections are just shown, so a redraw at any time will 
remove them.  Experiment by selecting all twelve lines at once 
(use select by crossing if you wish).  Notice that if you select 
more than one entity all of the sections are placed on top of one 
another.

Now let's use the 2D Sections command to show, then draw a 
cross-section. From the Explorer pulldown select the 2D Sections 
command.  We will use the default settings.

After clicking OK, you are prompted to select a line of section. 
Select one and press return.  Next you are prompted Show/Draw/
Redraw.   SHOWing a section displays the section in the current 
viewport temporarily, with no entities drawn into the AutoCAD 
drawing.  Any subsequent redraw, pan or zoom will remove the 
temporary display.  Type "S" followed by a return to use the 
SHOW option to preview your section.  Next you are prompted to 
specify a window within which to place the section.  The section 
is shown within the specified window.  This is an accurate pre-
view of the section we are about to draw, except without any text.

Now let's draw the section.  Select 2D Sections from the Explorer 
pulldown, click OK and select a line of section.  Press "R" fol-
lowed by a return at the Show/Draw/Redraw prompt to refresh 
the screen, then press "D" followed by a return to draw the sec-
tion.  The section will now be drawn in the window you specify.

Until now we have been using the default settings for 2D sec-
tions.  You have complete control over the characteristics and 
scaling of your 2D cross-sections.  Let's set a specific scale and 
vertical exaggeration, rather than using interactive scaling.  Select 
Setup > 2D Section Properties from the Explorer pulldown menu.

This dialog box accesses most properties of 2D cross-sections.  
Let's just set a few.  Assume we want to build a 2D section in 
model space with a vertical multiplier of 6 times but be at a 1:1 
horizontal scale.  Select the Graph button on the dialog box.

This invokes the graph dialog which controls most scaling param-
eters.  Click on the Scaled to Fit button in the Scaling section to 
remove the X.  This enables manual scaling.  Put 6.0 in the Verti-
cal multiplier edit box and verify there is 1.0 in the Horizontal 
multiplier edit box.  This will give us the desired 6:1 vertical 
exaggeration on our 2D cross-section.  Verify that the check 
boxes to the left of Ticks, Grid, and Numeric Label do not have 
an X in them.  This indicates we don't want to draw these ele-
ments.  Click on the OK button to exit the Graph sub-dialog, then 
click on the OK button to exit the 2D Section Properties dialog.

Now draw the section by selecting the 2D Sections command 
from the Explorer pulldown menu, click OK, select a line of sec-
tion and answer "D" for draw at the Show/Draw/Redraw prompt.  
DRAWing a section causes the cross section to be drawn into the 
AutoCAD drawing as entities (2D polylines, text, hatch, etc.).  
This makes the section part of your drawing.  Notice that now 
you are prompted for a lower left corner of the section to be 
drawn, rather than a window.  This is because you have specified 
fixed scaling rather than automatic scaling.  Select a point with 
the mouse on your display for the lower left corner of the section 
to be drawn.  Upon pressing the pick button the section will be 
drawn.

You may want to erase this cross-section and show or draw others 
while experimenting with the settings in the Setup > 2D Section 
Properties dialog and its sub-dialog boxes.  About the only trou-
ble you can get into is combining a hatched cross-section and a 
huge scale, causing a large drawing file to be created.

In the next section we will learn how to lay out multiple cross-
sections.  If you are going to continue to that section now, stay in 
this drawing because we will use the same data set and lines of 
section.

Building multiple 2D Cross-sections

This section assume you have the DEMO dataset loaded and the 
twelve polylines drawn as lines of section as used in the previous 
tutorial immediately above.  If you do not have the dataset 
loaded, load it now and draw the polylines as described in the 
previous section.

Now let's show all twelve cross-sections laid out in an array of 
three sections across by four down.  To do this, select the Setup > 
2D Section Properties command.

Select the All Defaults button to reset any changes you may have 
made.  Now select the Layout button. 

At the bottom of this box, select the Multi-Section Layout button.

Enter the number 4 in the Rows edit box and the number 3 in the 
Columns edit box.  This will produce an array of sections laid out 
in three columns by four rows.  Select the OK button of each dia-
log box until you are back at the AutoCAD command prompt.

Select the 2D Sections command from the Explorer menu and 
answer OK.  Select all twelve lines of section, then answer "S" 
for show at the Show/Draw/Redraw prompt.  You are now 
prompted for a window which represents only the upper left 
cross-section of the group of sections you are about to draw.  It is 
important to remember that the box you are drawing is the size on 
one cross-section, not all twelve.  Indicate a window about one 
inch high by two inches wide in the upper left portion on your 
screen.  The twelve sections will now be shown laid out as we 
indicated in a three by four array.

We have used the defaults here, but you have complete control 
over section spacing and arrangement.  You may want to experi-
ment with the settings in the Multi-Window Layout dialog box 
where we set the 3 columns and 4 rows settings.  Using SHOW 
rather than DRAW allows you to experiment without cluttering 
up your drawing while experimenting.  Remember that text label-
ing is not displayed on a SHOWn section, but will be displayed 
on a DRAWn section if specified.

Building a 2D cross-section with well logs

Leaving gaps in a 2D cross-section for subsequent addition of 
borehole log graphics is easy.  The next part of the tutorial uses a 
few pre-defined blocks, so open the drawing file DEMO.DWG 
prior to continuing.  This drawing has the blocks defined within 
it.  The intervals and surfaces we have loaded are still available 
and we need not reload them.  We will specify that we want wells 
on our sections and set the width of the well gap by using the 
Wells button of the 2D Section Properties dialog box.  Wells are 
only inserted when the line of section is snapped exactly to 
INSERTs (blocks) representing wells.  A set of four well symbols 
have been included in the DXF file demo.dxf in the directory in 
which Spatial Explorer was installed (\SPE1 by default).

Let's start by DXFing in the well symbols.

DXFIN   Select DEMO from the right side of the dialog box.

This loads four well symbol blocks.  In this case the blocks have 
attributes of ID and Welltype.  The attributes are included so you 
can see their behavior with 2D cross-sections.

This section assumes you are doing the tutorial in order and have 
the Demo dataset and the Demo setup file loaded and have used 
the Show TIN command from plan view. If you do not have the 
dataset loaded, load it now.

Type OSNAP and then INS to set snapmode to INSERT.  Now 
use the PLINE command to draw a polyline connecting the wells 
from left to right.  The direction of the 2D cross-section is depen-
dant upon the direction you draw the line of section.  The first 
vertex of the line of section polyline will be the left end of the 2D 
cross-section.  The Swap ends command is available to swap the 
vertex order if your have drawn the line of section in the wrong 
direction.  Now that you have drawn the line of section, type 
OSNAP, then NONE, to turn off object snap.

Now select Setup > 2D Section Properties from the menu.  We are 
going to set vertical and horizontal multipliers, then set the well 
options.  First, select the Graph button to invoke the graph sub-
dialog.  Click on the Scaled to Fit check box to de-select it, then 
enter 1.0 as the Horizontal multiplier and 6.0 as the Vertical Mul-
tiplier.  This will give us 6:1 vertical exaggeration.  Select the OK 
button.

Now select the Wells button to invoke the Wells sub-dialog.  
Check the Well Logs check box to indicate you want gaps left for 
wells.  Enter 1000 in the Well Width edit box (model space) to 
indicate that the width of the gap left in model space drawing 
units.  If you were drawing your section into paper space the 
value in the paper space edit box would govern.  Select the Sym-
bols check box to indicate we want well symbols above the well 
gaps on the section.  Also select the Auto scale check box.  The 
blocks representing well symbols are copied from the map to the 
2D section.  Auto scale causes the symbols to be scaled by the 
Horizontal Multiplier specified in the 2D Section Layout dialog.  
If this is not acceptable the symbols may be adjusted by de-select-
ing Autoscale and specifying a symbol multiplier in the edit box 
(.5 for half size; 3.0 for triple size).

Setting well gaps for 2D sections

Select OK on both dialogs to return to the AutoCAD command 
prompt.  We have set the options for wells symbols and are ready 
to draw the 2D cross-section.

Select the 2D Sections command from the pull down menu, click 
on OK and select the polyline you drew for a line of section.  
Answer Draw at the Show/Draw/Redraw prompt and select a 
point at the lower left area of where you wish the section to be 
placed.  The section will be drawn with the well gaps as 
requested.  Notice that the well symbols have their attributes with 
them as they existed on the map.  If several blocks are inserted 
exactly on a vertex of the line of section all of them are copied to 
the cross-section.

Building a 3D Fence diagram

A 3D Fence diagram is built by drawing "lines of section" con-
sisting of lines, circles or polylines overlying your defined sur-
faces then using the 3D Models command to draw the fences.  We 
have done the first step by defining the desired intervals and their 
properties.

This section assumes you are doing the tutorial in order and have 
the Demo dataset and the Demo setup file loaded. If you do not 
have the dataset loaded, load it now.  Erase your previous work.

The next step is to be sure that the lines of section overlie the sur-
faces you wish to section.  If you are not in plan view, change to 
plan view.  From the Explorer pull-down menu, select the Show 
TIN command.  A list of surfaces will be presented in a dialog 
box.  Select any surface name (try LIMESTONE) and the current 
viewport will be zoomed to overlie the surface and the TIN (Tri-
angulated Irregular Network) will be shown temporarily.  The 
TIN is the network of triangles which interconnect your control 
points.  Every vertex represents a control point of your data set.  
Because the TIN is SHOWn, not drawn, it will disappear the next 
time the screen is redrawn (by REGEN, REDRAW, PAN, ZOOM, 
VPOINT, etc.).

The following figure shows the TIN in lighter grey and the three 
polylines which you are to draw in darker lines. Use the PLINE 
command to draw the three polylines shown.  The exact position 
is not critical. 

It is more informative to watch the fence diagrams being built in 
3D, so let's use the VPORTS command to have multiple views.  
Type VPORTS and press return twice to accept the defaults of 
three viewports and the right viewport being larger. Type 
VPOINT followed by a return, then answer 1.3,-4.0,1.3 followed 
by a return to set an oblique view in the right viewport.  Pan as 
needed to look similar to the picture below.  Click on the lower 
left viewport to make it active, then use the VPOINT command 
again to set the viewpoint to -3,1,2. This will allow you to see 3D 
models construction as it occurs.

Pull down the Explorer menu and select the 3D Models com-
mand.  This will bring up a dialog and allow you to choose struc-
tures to draw, vertical exaggeration and fill mode.  Click on 
"Fences" as the structure to draw, enter "6.0" in the vertical exag-
geration edit box, and click on "Solid" as the fill mode.  The dia-
log will look like the following figure.

Selecting the OK button removes the dialog box and prompts you 
to select objects. In this case we are building fences, so select the 
three polylines you have drawn. Selection may be made with any 
of the standard AutoCAD selection methods such as window, 
crossing, etc. The fence diagram is now built as polyface meshes 
underlying each of the three lines of section selected.  Fences are 
fully three dimensional objects which may be viewed from any 
angle.  If you have crossing fences, as we have in this example, 
build them all in one pass as we have done here.  When given 
crossing lines of section in one selection, Spatial Explorer 
resolves each intersection and adds vertices at those intersections 
to insure exact matches between crossing sections.

Your model should look similar to the following figure.  Pan or 
zoom as needed.

Fence diagram in multiple viewports

The demo data set is from the deep subsurface of Wyoming and 
the surfaces are at an elevation of -3000 feet, and because we are 
using 6X vertical exaggeration the model is built around -18,000 
feet on the Z axis.  Your model with exaggeration will appear 
below the zero plane for surfaces with negative elevations and 
above the zero plane for surfaces with positive elevations.  At a 
vertical exaggeration of one, the fence diagram will be drawn at 
its actual elevation.

Shading makes fence diagrams much easier to interpret.  
AutoCAD's SHADE command can shade in four different modes 
controlled by the SHADEDGE system variable (described on 
page 300 of your AutoCAD R12 Reference Manual).  The results 
you get are a function of your video card, driver and video con-
figuration.  For best results with the shade command have your 
system configured for 256 colors.  If you only have 16 colors, set 
SHADEDGE to 2 or 3.  Set the SHADEDGE variable by typing 
"SHADEDGE" and type 3 followed by a return.  Make the right 
viewport active by clicking on it, then type SHADE and a return.  
The shade command regenerates the drawing and then creates a 
shaded display.  The current viewport is what is shaded.

Experiment with the different settings of SHADEDGE for your 
particular configuration by setting SHADEDGE, then SHADE-
ing.  The SHADEDGE settings are 0 for shaded faces with no 
edge highlighting; 1 for shaded faces with highlighted edges; 2 
for simulated hidden line rendering; and 3 for solid color faces.

AutoCAD's RENDER command will also produce good images.  
You will need to increase the Ambient light and perhaps add 
lights to produce acceptable images.

Any image rendered with SHADE or RENDER may be captured 
with AutoCAD's SAVEIMG command (page 130 AutoCAD Ren-
der Reference Manual) as a GIF, TIFF or Targa file and plotted or 
made into a color slide by a service bureau.  Files saved with 
SAVEIMG may be shown within AutoCAD with the AutoCAD's 
REPLAY command (page 110 AutoCAD Render Reference Man-
ual).  Many other file viewers will also display these file formats.

The "Solid" fill mode we chose builds fences as polyface meshes.  
These are space efficient and SHADE and RENDER nicely, but 
will not plot as solid-filled with most standard AutoCAD plotter 
drivers.  The "Hatch" fill mode is supplied for those wish a 
hatched model for plotting on small plotters and laser printers.  
Hatched models are immense by nature and should be avoided 
unless explicitly needed as they are slow to generate and take lots 
of disk space.

At this point you may want to save this model to use later in the 
3D annotation exercise.  The hatching we are about to create will 
just slow you down.

We will now build a hatched model.  You will need about 10 
megabytes of free disk space to do the next step.  Let's clean up 
before we proceed.  When building large models, you can save 
disk space and increase speed by disabling AutoCAD's UNDO 
command.  Type "UNDO", then "C" for control, then "NONE" to 
disable the UNDO command.  Later you may re-enable it by typ-
ing "UNDO", then "C", then "ALL".  

From the Explorer pulldown, select 3D Models and leave the 
Structures to Draw as Fences, but change your selection from 
Solid to Hatch, and also change vertical exaggeration to 5.0.  This 
will draw a hatched fence diagram above the previous solid 
fence, because we have reduced the vertical exaggeration and our 
surfaces are at negative elevations. Select the OK button, then 
select the three polylines you drew as lines of section.  The 
hatched model is now drawn.  Watch the UCS icon as the model 
is built.  The model consists of a white polyface mesh represent-
ing the fence, then closed 2D polylines and the hatch fill for each 
interval drawn in two vertical planes, slightly offset on either side 
of the vertical polyface mesh.  This complex geometry is drawn 
so you may do hidden line plots or renderings and have the hatch 
pattern hide properly.  The details of the 3D model geometry is 
described in Chapter 7.

Once the hatched fence is complete, zoom in on it from an 
oblique view.  You may plot this with hidden lines enabled from 
any viewpoint.  Using SHADE with SHADEDGE set to 2 will 
give you a preview similar to a hidden line plot, but much more 
quickly.

Annotating your 3D model

If you saved your non-hatched model from the previous exercise 
recall it now.  You may use a hatched model if you wish in this 
exercise, but 3D Annotate causes some REGENs, which will be 
slow if the hatch patterns are present and thawed.

Annotating your 3D model is easier from a single large viewport 
rather than the multiple viewport setting we have, so type 
"VPORTS", a return, "SI" for a single viewport.  Set to an oblique 
view using VPOINT if not already in one.

The 3D Annotate command places you in a user coordinate sys-
tem with its XY plane parallel to the selected fence face and 
slightly offset toward you from the fence face. This allows you to 
draw anything including text and polylines or to insert blocks 
(such as borehole logs) on the fence face.  If the text has non-zero 
thickness, all annotation will hide properly.

This section assumes you have a 3D fence diagram already drawn 
as described in the previous section.

From our oblique view, select 3D Annotate from the Explorer 
pulldown.  You are prompted to select a fence face for annotation.  
Select the face or hatch pattern and your view and UCS will be 
changed.  The drawing will regenerate and place your viewpoint 
perpendicular to the selected fence face, with the UCS such that 
+Y is up and +X is right and the selected fence face fills the 
screen.  A REGEN is typically involved.  After the command is 
finished, you may zoom and pan as required.  If you have several 
sub-parallel fences, you may have several fences superimposed, 
but the annotation you add will be registered properly to the 
selected face.  You may now use any AutoCAD command to 
draw annotation in this UCS.  Blocks may be inserted and scaled 
to fit.  Common blocks might represent well logs or wellbore dia-
grams which were created in the XY plane prior to being made 
into a block.

For text to hide properly, AutoCAD requires it to have a non-zero 
thickness.  This limitation also applies to text within blocks.  Zero 
thickness text disappears in hidden line plots.  Unfortunately 
AutoCAD creates text with zero thickness, regardless of the set-
ting of the THICKNESS system variable.  You may change the 
thickness of text subsequent to its creation with the CHANGE or 
CHPROP commands.

We have found several bugs in AutoCAD Release 12 hidden line 
routines, the most bizarre being that if you place text on the same 
layer as a polyface mesh, the hidden line routine doesn't hide any-
thing.  This AutoCAD bug affects the HIDE and PLOT (with hid-
den lines) commands.  The SHADE command with SHADEDGE 
set to 2 emulates the HIDE command and functions properly.  
The Release 11 HIDE algorithm is slow, but works correctly.  
This R11 algorithm is available in Release 12 and is accessed via 
the Configure Operating Parameters selection of the main 
AutoCAD configuration menu.  See the AutoCAD Installation 
and Performance Guide under Hidden Line algorithm.

If you experience problems with text and hidden lines, try experi-
menting with text style, thickness and text offset distance. Text 
offset distance is set via the Define Intervals dialog box and the 
Options button.  Schreiber Instruments will make work-around 
methods for AutoCAD's hide bugs available on the BBS as they 
are determined.

For this tutorial let's insert one block representing a borehole log, 
draw a polyline on the face and label the SHALE-UNCONFOR-
MITY interval (second from the top) with the word "Shale".

First, create a new layer upon which to place your annotation.

Use the DTEXT command to place the word "Shale" on the face 
you selected.  Choose the height, rotation, etc. interactively.  
Once you have placed your text, type CHPROP and a return to 
invoke the Change Properties command of AutoCAD.  Select the 
text entity you have just drawn and enter TH (for thickness) as the 
property to change and enter a new non-zero thickness (try 1.0).  
The thickness should be a small positive value.  The actual value 
is dependant upon the extents of your model.  Changing the thick-
ness allows the text to render and hide properly.  Another return 
finishes the CHPROP command.

Draw a polyline on the face.  It might represent an interpretation 
of a projected fluid level or pressure change.  

Command: pline

From point: pick a point
Current line-width is nnn
Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: W
Starting width <0.0000>: 20
Ending width <0.0000>: 20
From point: pick a point
From point: pick many points to define your line 

Now we'll insert the pre-defined block (BOREDIAG) represent-
ing a borehole diagram.

Command: insert    Block name (or ?): BOREDIAG

Insertion point: Select the top center of the top fence face
X scale factor <1> / Corner / XYZ: 1
Y scale factor (default = X): 1
Rotation angle <0>: 0

There are many different ways to create, scale and place blocks 
using AutoCAD.  The method you use depends on the units and 
scale of the components making up the block to be inserted.  You 
may want to create blocks one unit high and one unit wide and 
use the Corner scale factor option of the insert command.  Alter-
natively, if the Y units within the block represent depth in draw-
ing units, you may specify the X and Y scale factors discretely, 
with the Y scale factor equalling the Vertical exaggeration used 
during fence construction.

Use the 3D View command from the Explorer pulldown to 
choose an oblique view which we will quickly render using 
SHADE.  The 3D View command does two things: it sets the 
view and also resets to World Coordinates.  When you use the 3D 
Annotate command, you are left in a UCS when finished. 
Remember to reset to World Coordinates prior to further drawing.  
This may be accomplished using the UCS, 3D View or Map View 
commands.

Now let's SHADE the annotated fence diagram by typing 
SHADE and a return. Remember that the SHADEDGE variable 
controls the type of shading.  You may want to experiment with 
changing thickness of your annotation to enhance it in shaded 
renderings.

The 3D Annotate command only works with entities created by 
Spatial Explorer and may not be used to annotate polyface 
meshes drawn by other means.

Building a 3D Block model

A 3D block model is built out of two components: a fence dia-
gram built based upon a line of section which is a closed polyline; 
and one or more surface meshes drawn within the closed line of 
section.

This section assumes you are doing the tutorial in order and have 
the Demo dataset and the Demo setup file loaded and have used 
the Show TIN command from plan view. If you do not have the 
dataset loaded, load it now.  Erase any previous sections.

You may see the operation of the 3D Models command with a 
multi-viewport setting. So do the following:

Command: VPORTS

Save/Restore/Delete/Join/Single/?/2/<3>/4: Restore and answer 
3DBLOCK

3D Block model

Click on the upper left viewport to make it current and use the 
Show TIN command to display the TIN representing your data.  
Using the PLINE command, draw a closed polyline representing 
the edges of the block model.  Be sure that the polyline lies within 
the area where your surfaces are defined.  This polyline will also 
determine the edge of any surface meshes drawn.

Now we must specify which defined surface(s) should be drawn 
as surface meshes.  Select the Setup > Define Intervals dialog 
box.  Select the Surfaces button to invoke the Surfaces to Draw 
dialog.  Use the Surface pop-up list in the upper right part of the 
Dialog to select LIMESTONE as a surface.  Use the Layer pop-
up list and its Create layer selection to create a layer named CAP 
upon which to place the LIMESTONE surface mesh.  Use the 
Color pop-up list to select Cyan as the color.  Select ACCEPT to 
place these definitions in the surface definitions list.  If you have 
two definitions for the LIMESTONE surface (due to a pre-exist-
ing one) use the Delete Selected button to delete one of them.  
Click on OK on each box to return to the command prompt.

Now select the 3D Models command from the Explorer pull-
down.  Select Fences and Surfaces as the structures to draw by 
checking the check boxes to their left.  Specify a vertical exagger-
ation of 6.0 in the edit box. Select the Solid fill mode, then click 
on OK.  Select the closed polyline you drew at the Select Objects 
prompt.

The walls of the block model are drawn as fences and the cap is 
drawn as a surface mesh.  Different views of the models should 
be visible in each viewport.

Click on the lower left viewport, zoom as needed and type 
SHADE to do a quick shaded view.  By experimenting with the 
SHADEDGE variable, then using SHADE again, you can deter-
mine which combination looks best on your display.

Now would be a good time to experiment by building 3D block 
diagrams starting with different lines of section.  Make the upper 
left viewport current by clicking on it, then erase everything.  If 
you have the TIN displayed, it will not erase, because it is 
SHOWn and is not an AutoCAD entity.  A redraw will remove it, 
but leave it up, as it is a useful reference.  Experiment with the 
following as lines of section: a circle; two overlapping closed 
polygons; two or three nested circles; a circle which extends past 
the edge of the data (as shown by the TIN).

Building a 3D Wellbore model

This section assumes you are doing the tutorial in order and have 
the Demo dataset and the Demo setup file loaded and have used 
the Show TIN command from plan view. If you do not have the 
dataset loaded, load it now.

You may see the operation of the 3D Models command with a 
multi-viewport setting.  So do the following if needed:

Command: VPORTS

Save/Restore/Delete/Join/Single/?/2/<3>/4: Restore and answer 
3DBLOCK

Click on the upper left viewport to make it current.  Use the Show 
TIN command to display a TIN of any surface, to insure we over-
lie the surfaces.

We are going to draw several different types of entities to use for 
3D Wellbore positioning.  Use the POINT command to draw four 
or five points.  Next use the PLINE command to draw a polyline 
with four vertices.  Lastly, DXFIN the file DEMO which contains 
four INSERTS  representing well symbols.

The Wells option of the 3D Models command allows us to build 
stacked 3D cylinders representing vertical wellbores.  We specify 
the XY location of the wells and Spatial Explorer uses the 
defined intervals to draw the 3D wellbore representation.  The 
well XY locations are defined by extracting the X,Y location of 
the selected objects, which may include points, polylines and/or 
blocks.  The wellbore locations used are the X,Y of points, the 
vertices of 2D or 3D polylines or insertion point of blocks.  Let's 
explore these settings.

Select Setup > Define Intervals from the Explorer pulldown.  
Click on the Wells button to invoke the Wells sub-dialog.  Here 
you will specify the radius of the wellbore in drawing units and 
which entity types will have wellbores drawn at them.

Fill in the Well Radius edit box with 75.0.  This indicates that the 
radius of each 3D wellbore will be 75 drawing units.  The appro-
priate radius is dependent on the inter-well spacing, the closer the 
wells, the smaller the radius.

The next section of the dialog indicates which entities have 3D 
wellbores drawn at them.  You may select one or more of the 
check boxes.

First, just check the Wells at Points check box and de-select the 
other two.  Select OK on the two dialog boxes to return to the 
command prompt.

Select the 3D Models command and select only Wells as the 
structures to draw.  Set the Vertical exaggeration to 6.0 and Solid 
fill mode, then click on OK.  At the Select Objects prompt select 
the points, polyline and wellbore blocks.  The 3D wellbores will 
just be drawn at the POINT entities because we chose Wells at 
Points Only in the dialog box.  The combination of the dialog 
selection (Wells at ...) and the entities selected upon execution 
control where 3D wellbores are created.  Erase the existing 3D 
wellbores so we may create a different set.

Select Setup > Define Intervals, then the Wells button, and select 
Wells at Points and the Wells at Vertices check boxes.  Click on 
OK of the two dialog boxes to return the command prompt.

Select the 3D Models command and pick OK, leaving the settings 
alone.  At the select objects prompt select the points, polyline and 
wellbore blocks.  The 3D wellbores will be drawn at both the 
POINT entities and each vertex of the polyline. 

3D Wellbores at points

Now erase the existing 3D wellbores again, so you can see the 
new ones we are about to create.

Select Setup > Define Intervals, then the Wells button, and de-
select Wells at Points and Wells at Vertices check boxes.  Select 
the Wells at Blocks check box.  A block selection box pops up, 
showing all of the blocks currently defined in the drawing.  You 
may select any or all of the blocks for 3D wellbore placement by 
clicking on them. Select the SPE_WELL block then OK.  If you 
change your mind, the blocks button invokes the block selection 
dialog again.  Click on OK of the two dialog boxes to return the 
command prompt.

Select the 3D Models command and pick OK, leaving the settings 
alone.  At the select objects prompt select the points, polyline and 
wellbore blocks.  The 3D wellbores will be drawn at the insertion 
points of the SPE_WELL blocks only.

The selection criteria of points, blocks or vertices may be used 
singly or in combination.  The 3D Wellbore diagram does not 
necessarily represent an actual well, it may show a hypothetical 
wellbore or simply be used as an illustrative model.  The surfaces 
you use may indicate meaningful surfaces representing stratigra-
phy, fluid levels or piezometric surfaces, or they may be phantom 
surfaces which may not have meaning away from the wellbore 
but are meaningful at the well location.  Such phantom surfaces 
could include intervals representing perforations, cores, samples, 
tests, gravel packs, etc. For example, you might create continuous 
3D wellbores representing stratigraphy at a given radius on one 
pass, then create discontinuous intervals representing perforated 
or tested intervals with a slightly larger radius in a second pass.  
When shaded or rendered, the result would be a continuous cylin-
der representing stratigraphy and bands representing the perfo-
rated or tested intervals.
