 |
Description  |
|
|
The present invention pertains to data processing systems for the location
of real estate properties for purchase through the use of an interactive
graphical locator interface for developing geographic area indications.
BACKGROUND OF THE INVENTION
Listings of available real estate are typically stored in a central
computer system, generally referred to as a "multiple listing service".
This computer-stored listing may be accessed through terminals for
retrieval of specific information relating to a given property. However,
search of the stored information is typically dependent on the operator's
intricate knowledge of the local area, its political subdivisions, and
informal housing tract designations. Furthermore, such listings are
usually maintained for each county, and multiple accesses of diverse
systems are often required for a complete location of all available
properties. Finally, no provision for searches by multiple criteria,
including geographic location is made in prior systems.
THEORY OF THE INVENTION
The system and method of the present invention comprises a host system for
maintaining a database of available properties, receiving data from both
buyers and sellers of properties, and searching the database using buyer's
criteria. The system and method of the present invention also comprises
seller and remote systems for creating, storing, updating, and
transmitting buyer and seller data to the host. The system and method of
the present invention are applicable for residential, commercial,
industrial and other special purpose uses of the real estate involving
sale, lease or rent. All geographic location performed by the system of
the present invention employs a graphical locator interface for specifying
property locations.
The user can create a property search file by selecting the "Create" option
from the Main Menu. A viewport is displayed and map boundaries are drawn
on-screen. Inside this display the user can control the position and size
of a "rubberband" window box. Properties appear as dots on the map.
A labeled distance indicator is displayed which calculates the distance
between the window box center and the selected landmark location. The user
can change the landmark location from a menu of landmarks. The label and
distance indicator are then updated automatically. As the user changes the
window box position, the labeled distance indicator changes to reflect the
distance from the displayed landmark. The user can center the window box
over the landmark automatically [via the home key]. Price and size minimum
and maximum indicators appear below the viewport. The user can change the
minimum and maximum indicators to refresh the points display. Only these
property points within the minimum-maximum limits are drawn. The data for
these points are referred to as the points file. The user can change the
size of the window box.
The user can then change the world coordinate display to equal the
boundaries of the window box. The size of the viewport remains constant so
that the display now appears to have zoomed down closer to earth. Map
boundary lines are displayed with greater detail and a "rubberband" circle
is displayed which allows the user to enclose a search boundary on the
map. The user can then either return to the original zoom-up display or
save the center location and radius values of the rubberband circle.
The labeled distance indicator is redisplayed and now calculates the
distance between the rubberband circle center and the current landmark
location. The user can change the size of the rubberband circle. A radius
indicator is displayed which calculates the radius of the rubberband
circle. As the user changes the position and size of the rubberband
circle, the labeled distance and radius indicators are updated to reflect
the changes.
Having entered the search location boundary, the user is then prompted for
the numerical range data entries.
Having selected numerical range data values, the user is then prompted with
a series of menus and asked for selections.
When the final menu is displayed and all data entries have been
successfully entered, the user has successfully created a property search
file and is returned to the Main Menu.
The present invention comprises a system of computer software for creating
and maintaining both a real estate property database and a corresponding
file of hard-copy real estate property listing advertisements, and for
allowing searches of the database. A "host system" having a database can
be searched from "remote" computer systems by the use of a public domain
software program that is menu driven and includes a graphical locator
interface to specify accurate search location boundaries.
The search facility enables a remote user to obtain a custom selected
portion of the hard-copy property listing file without having to obtain
the entire file. The search facility also enables the user to obtain many
different custom-selected sets of files from the hard-copy property
listing file.
The system of the present invention is implemented as three main computer
systems:
1. A host system which accepts both property listing files and property
search files from remote locations, maintains the property database and
performs searches, reports system errors, maintains customer accounts, and
calculates statistics. The host system has:
(a) Download options - news files and points files
(b) Search options - search summaries and custom searches
2. A property listing maintenance system which enables a remote user to
create and update a property listing file and then transmit it to the host
system.
3. A property search maintenance system that enables a remote user to
create and update a property search file and then transmit it to the host
system. The system also maintains archive files of searches that were
already processed.
Host Receiving System
The host system polls a standard telephone line while waiting for remote
data transmissions. When the host system receives a call, it brings the
telephone line off-hook. If a carrier signal is detected, the host system
conforms to the specified communication parameters and waits for incoming
data.
The host system downloads a data file using an XMODEM protocol. (downloads
user file with XMODEM). See 1. The host system then goes back on-hook and
polls the telephone line for more calls.
Any data transmission errors of spurious calls occurring after the host
system brings the telephone line off-hook causes the host system to hang
up and poll for more calls.
Maintain
Received data files are placed on queues set up for batch processing. A
search queue, an addition queue, and a deletion queue are all processed
for application to the property database. When batch processing in the
host system begins, the host reads the property database into memory and
processes the deletions queue. Next, the addition queue is added to the
property database. The updated property database is then sorted so that
the search queue may be processed. When all the search processing is
complete, the property database is then sorted again for filing and
over-written to the property database file on disk.
Custom Search
The search processing procedure compares property data records to the
search being processed. Minimum/maximum numerical fields in the property
data records are checked against the associated numerical ranges of the
search. Property data menu selections are checked against their associated
search menu selection arrays. The distance from the property data records'
location to the search area center location is calculated with the
distance formula and compared to the search boundary radius value. The
search processing produces several files that are used for further
processing. A file of search results is produced which contains an
identification for each search on the search queue plus a list (if any) of
the properties that were selected in the search. From this file, a file of
customer mailing labels is produced. Another file is also created which
contains a count of the number of times each property data record was
selected during the search processing. This simplifies hard-copy
duplication tasks and eliminates unnecessary duplications.
During the subsequent processing, hard-copy duplicates are made for
materials relating to each property selected. The results of each search
are collected and assembled from the duplicates and labeled for shipping.
The finished search results are then shipped to customers. See 2.
Accounting
Customer accounts are created and maintained by separating the customers
into two groups--Buyers and Sellers. Buyer accounts are used to search the
property data file while Seller accounts are used for property listings.
The Buyer account list contains records with identification data fields and
financial resource data fields. The Buyer account system interactively
prompts for new Buyer accounts--automatically assigning serial numbers,
and new payment data. The Buyer account list is then read into memory from
the Buyer account file so that new accounts and payments can be added. The
resource field that accounts for time on the system is automatically
updated. Buyer account records with deficient resource fields are
automatically deleted. The Buyer account file is then overwritten.
Similarly, the Seller account list also contains records with
identification data fields plus a resource data field. The Seller account
system interactively prompts for Seller accounts to be terminated, new
Seller accounts--automatically assigning serial numbers, and new payment
data. The Seller account list is then read into memory from the Seller
account file so that new accounts and payments can be added and
terminations processed. The resource field that accounts for time on the
system is automatically updated. Seller account records with a deficient
resource field are automatically deleted. The Seller account file is then
overwritten.
A log is written during the accounting process to document all entries. It
also serves to document any automatic processing which may occur.
Both the Buyer and Seller accounting systems produce receipt files which
are printed to inform the customer of the results of processing. Serial
numbers and payment receipts are issued in this manner. Seller
terminations receipts are also issued in this manner.
Statistics
The host system calculates statistics by reading the property data file
into memory and traversing the property database. Minimum, maximum, count,
percentage, mean, and standard deviation statistics are then calculated
where applicable and written to a file with all statistics being clearly
labeled. This file includes special printer functions so that a neat and
organized report can be printed. Price, size, X, and Y data are written to
the points file.
A system check routine is included to track potential errors in both the
Buyer and Seller accounting systems. In the Seller accounting system, the
Seller account file is checked against the property database and the
errors are reported. In both the Buyer and Seller accounting systems,
accounts with deficient resources are also reported.
Property Listing File Program
The Property Listing File Program is used to create, maintain, and transmit
property listing files to the host system. It interactively prompts for
entries, is error trapped, and requires no previous knowledge about either
the remote or host systems.
The user can create a property listing file by selecting the "Create"
option from the Main Menu. A viewport is displayed and map boundaries are
drawn on screen. Inside this display, the user can control the position of
a rubberband window box.
The user may then change the world coordinate display to equal the
boundaries of the window box. The size of the viewport remains constant so
that the display now appears to have zoomed down closer to earth. Map
boundary lines with erasable labels are displayed with greater detail and
a movable crosshair cursor is displayed which allows the user to pinpoint
a location on the map. The user can then either return to the original
zoom-up display or save the location of the crosshair cursor.
Having selected a location, the user is then prompted for the address of
the property. The user must enter an address.
Having entered the address, the user is then prompted for numerical
property data entries. If an invalid value is entered the user is again
prompted for the same input.
Having entered the numerical property data entries, the user is then
prompted for tracking directions to the property. If an invalid value is
entered, the user is prompted for the same input.
Having selected numerical property data values, the user is then prompted
with a series of menus and asked for selections. If an invalid menu
selection value is entered the user is again prompted for the same input.
When the final menu is displayed and all data entries have been
successfully entered, the property listing data is over-written to a disk
file. The user has successfully created a property listing file and is
returned to the Main Menu.
From the Main Menu the user can then choose to update the property listing
file currently on disk. By selecting the "Display/Update" option the
property listing data is read into memory and the Display/Update menu is
displayed to allow the user to update either the location, address,
numerical or menu data sections separately. When the user is finished
editing a section, he is returned back to the Display/Update menu to allow
him to edit another section.
The traveling directions update procedure displays the property address
data and allows the user to edit each portion of the address separately.
After editing a portion of the traveling directions, the entire traveling
directions are redisplayed. When the user is satisfied with the address
data, he is returned to the Display/Update menu.
The location update procedure is identical to the property listing
map/location interface described previously.
The numerical data update procedure displays the numerical data and allows
the user to edit each portion separately. After editing a portion of the
numerical data, the numerical data is redisplayed. When the user is
satisfied with the numerical data, he is returned to the Display/Update
menu.
The menu data update procedure displays the menu data and allows the user
to edit each portion separately. After editing a portion of the menu data,
the menu data is redisplayed. When the user is satisfied with the menu
data, he is returned to the Display/Update menu.
When the user is satisfied that the property listing file is complete, he
can select the "Print" option from the Main Menu to print the Property
Listing File. The property listing data is read into memory and copied to
the printer with each value clearly labeled. When the printing is
completed, the user is returned to the Main Menu.
The completed property listing file may be transmitted to the host system
by selecting the "Send" option from the Main Menu. The user is then
prompted for account identification data. The property listing file is
read into memory and the account identification data added to it. All
dialing and communications parameters are set automatically and the
program takes the remote system off-hook and dials the host system. The
remote system then waits for a carrier tone. If no carrier is present the
remote system times-out and returns a diagnostic error message to the
user. If a problem exists with the remote system while off-hook, the
program brings the system back on-hook and displays a diagnostic error
message or aborts processing.
If the remote system receives a carrier tone from the host system, the
connection is established and the remote system uploads the property
listing file to the host system using the XMODEM protocol. The remote
system then waits for a diagnostic message from the host system and
displays the message to the user. The program then brings the telephone
line back on-hook and returns the user to the Main Menu.
Property Search File Program
The Property Search File Program is used to create, maintain, and transmit
property search files to the host system. It interactively prompts for
entries, is error trapped, and requires no previous knowledge about either
the remote or host systems.
From the Main Menu the user can then choose to update the property search
file currently on disk. By selecting the "Display/Update" option the
property search data is read into memory and the Display/Update menu is
displayed to allow the user to update either the location, numerical
ranges or menu data sections separately. When the user is finished editing
a section, he is returned back to the Display/Update menu to allow him to
edit another section. When the user is finished updating the property
search data, the property search data is over-written to the disk file and
the user is returned to the Main Menu.
The location update procedure is identical to the search location map
interface described previously.
The numerical range data update procedure displays the numerical range data
and allows the user to edit each portion separately. After editing a
portion of the numerical range data, the numerical range data is
redisplayed. When the user is satisfied with the numerical range data that
is displayed, he is returned to the Display/Update menu.
The menu data update procedure displays a category menu to allow the user
to edit each portion of the menu data separately. After editing a portion
of the menu data, the menu data is redisplayed. When the user is satisfied
with the menu data, he is returned to the Display/Update menu.
When the user is satisfied that the property search file is complete, he
can select the "Print" option from the Main Menu to print the Property
Search File. The property search data is read into memory and copied to
the printer with each value clearly labeled. When the printing is
completed, the user is returned to the Main Menu.
The completed property search file may be transmitted to the host system by
selecting the "Send" option from the Main Menu. The user is then prompted
for account identification data, search name data, baud rate data, and
dialing prefix data. The property search file is read into memory and this
data is added to it. The remaining communications parameters are set
automatically and the program takes the remote system off-hook and dials
the host system. The remote system then waits for a carrier tone. If no
carrier is present the remote system times-out and returns a diagnostic
error message to the user. If a problem exists with the remote system
while off-hook, the program brings the system back on hook and displays a
diagnostic error message or aborts processing.
If the remote system receives a carrier tone from the host system, the
connection is established and uploads the request to the host system.
After waiting for processing, it downloads the results. The program then
brings the telephone line back on-hook and returns the user to the Main
Menu.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is an overall block diagram of a system typical of the present
invention.
FIG. 2 is a functional block diagram of the system of the present
invention.
FIG. 3A is a depiction of a map generated on a CRT according to the present
invention.
FIG. 3B is a map showing greater detail and displayed on a CRT according to
the present invention.
FIG. 4 is a flow diagram of the procedure create buyers search
specification file.
FIG. 5 is a flow diagram of the procedure obtained new center and radius
for display circle.
FIG. 6 is a flow diagram of a generalized procedure for the zooming of the
map display of the present invention.
FIG. 7 is a more detailed flow diagram of the procedure close SRPROP.DAT
and upload data to host system.
FIG. 8 is a more detailed flow diagram of the procedure upload request to
host computer and prompt for CR.
FIG. 9 is a flow diagram of the procedure maintain data base.
FIG. 10 is a flow diagram of the procedure receive buyers search
specifications.
FIG. 11 is a flow diagram of the procedure receive file from remote system
and acknowledge.
FIG. 12 is a flow diagram of the procedure search data base of properties
using buyers specifications.
FIG. 13 is a flow diagram of the procedure update accounting data for
buyers and sellers.
DETAILED DESCRIPTION
Referring now to FIG. 1, there is shown an overview block diagram of the
entire system of the invention which includes a host computer system 200
which is connected by telecommunications links 20 to a plurality remote
computer systems 100A, 100B and 100C. Host system 200 maintains a database
of property listings 202 which contains a plurality of property listings
submitted by those with properties to sell, lease or rent. The database is
used for search and delivery of relevant property information to those
inquiring of the system with certain specifications to be described later.
Host system 200 also maintains a set of client accounts 204, one account
per client (either a buyer or seller). Charging for the use of the system
is based upon a continual update of these client accounts. Host system 200
also uses a mail service 30 such as the U.S. mail service (but not limited
thereto) for communication and billing purposes. Each remote system, 100A,
100B and 100C, is capable of interrogating the database 202 by
communicating a set of specifications for a desired property to be
purchased to host system 200. These specifications are derived from buyer
input data 12A, 12B and 12C. The buyer input data is interactively
gathered from the buyer by the remote system, formatted, and transmitted
with an error-checking protocol to the host system. The host system either
processes the search data (also points files and news files) on-line and
returns a summary result or batches the interrogation requests for
subsequent processing off-line. Similar to the communications functions by
host system 200, communications also occur with sellers and remote system
operators through mail service 30.
Referring now to FIG. 2, there is shown a procedural overview block diagram
of the present invention. The system 10 of the present invention comprises
three principal components, host system 200, remote system 100, and seller
system 500. It will be understood that although only one seller system 500
is shown, a plurality of such systems exist and interface to host 20 .
Similarly, although only one remote system 100 is shown a plurality of
such systems exist and interface to host 200. The procedural components of
host system 200 include maintain database procedures 210, search database
procedures 260 receive buyers search specification procedures 230, prepare
output of search result procedures 280, statistical analysis procedures
290 (which includes generation of the points file which consists of X, Y,
price and size data values for each property), and accounting procedures
300.
Maintain database procedures 210 first deletes listings that are no longer
of use and then adds new listings to the database. The source of new
properties in the database is seller system 500 wherein complete
specifications are prepared and delivered to host system 200 through a
variety of means. Database maintenance procedures 210 also include an
additional amount of information added through a location system for new
properties to be described later.
Database search procedures 260 include an application of buyer search
specifications to the database. The receiving of buyer search
specifications is conducted via telecommunications link 20 depicted in
FIG. 1. Remote systems according to the present invention are interfaced
via a modem or other such telecommunications device to host system 200
which controls its own telecommunications line and receives information
from remote systems with validation and error-checking procedures. On
receipt of such valid information a search specification is built within
host system 200 and is queued for later processing during an off-line
period in the host. Receipt of a buyer specification file is acknowledged
to the remote system and a status message is delivered prior to
termination of the telecommunications link. The output of a database
search, if successful, is either a summary of the property record or will
include a listing of a given buyer identification number followed by the
serial numbers of those property listings in the database which fall
within the range of specification created by the buyer. This listing which
pairs buyers with located properties then permits further processing in
host system 200.
The output listing from host system 200 is stored in three files. The first
file is the identification of the search which identifies the actual
buyer, the search name, and the serial numbers of any properties which
have been selected. In addition, a list of mailing labels is created with
the names and addresses of the buyers for whom searches have been
performed. This list of mailing labels is created by referencing the buyer
identification number against the host system accounting files.
Another procedure in host system 200 counts the number of times each
property listing serial number was selected during batch processing and
writes that information to a file, Subsequently duplicates of the
individual property advertisements are made. Then, during further
processing, the searches are collected from these duplicates and placed
with the printed search results into an envelope with the corresponding
mailing label and shipped to the buyer.
Another function of host system 200 is accounting functions 300. These
accounting functions include charging for services rendered to both
sellers and buyers. Sellers are charged by the number of days that their
property advertisement is listed in the database. The buyer is charged by
the search. The type of search can involve varying costs.
Typically the charge to buyers is done on a declining balance arrangement,
wherein a minimum charge of a certain number of requests is applied
regardless of the outcome of any search, including invalidity of search
data.
Yet another function of host system 200 is statistical analysis functions
290. Statistical analysis may occur on the total contents of the database
at any given time, the average contents of the database over a longer
period of time, or statistical analysis may be performed to detail the
nature of search specifications being transmitted to host system 200. X, Y
price & size points file is written.
There are three basic types of variables used in the system of the present
invention: (1) numerical; (2) array or menu selection; and (3) floating
point location. Average minimum, maximum and standard deviation is
computed for numerical data. Finally a count of the number of property
listings in the database and a percentage of those with a mortgage, and an
average mortgage rate are calculated. A second major component of system
10 is remote system 100. Remote system 100 is comprised of two principle
sub-systems: create search specification file 110 and transmit search file
150. Create search specification file 110 is the module seen by potential
buyers of properties wishing to interrogate host system database 202. The
unique user interface incorporated within module 110 includes a graphical
locator which permits precise location of desired area for property
purchase with reference to a global coordinate system. This location is
selected through the use of manipulator keys or pointing devices such as a
mouse, light pen or other known devices which allow positioning of a
graphical interface selector in order to locate both property location and
distance specifications without resort to numeric data on the part of the
user.
From the main on-screen menu, the user selects the create option. The
system displays the graphical locator interface which draws a map on the
display (shown in FIG. 3A) with points indicators. Superimposed over the
map is a window box that is non-destructive. The user has control of the
position and size of the window box through a set of keys or locator. Also
on-screen is a distance indicator which calculates the distance in miles
from the center of the window box to a changeable landmark location on the
map. The user can display a list of landmarks; change the selected
landmark and the actual display is automatically updated. The landmark is
also labeled on the map. The minimum/maximum indicators appear below the
viewpoint. These indicators can be changed so that when refreshed, only
those points whose price and size are within the minimum/maximum limits
are displayed. The user can also automatically center the window box over
the current landmark. After selecting the landmark, moving the window box,
and selecting its size, the user activates a key sequence to "zoom" the
display. In other words, the viewport will then display the actual
boundaries of the window box so that display appears to have zoomed down
closer to earth (shown in FIG. 3B). A "rubber band" circle then appears
which is normalized to the size of the viewport. The user may move this
circle on the display and also change its size. There is displayed a
radius indicator indicating the actual radius of the circle in miles along
with a corresponding distance indicator from the specified landmark. Once
the user has selected his search boundary by selecting an appropriate
circle, that data may be saved or changed.
After saving the location data, the user is prompted for numerical range
data, such as minimum and maximum price for the target listing. After
having selected several numerical ranges, a series of menus are displayed
so that the user may select one or several selections on each menu.
After the completion of the questioning cycle, all data entered by the user
is stored as a search specification. The user is then allowed to print
hard copy of the search specification prior to subsequent transmission of
the search specification to the host system. A second procedure allows
editing of a previously created search specification. This process termed
"update" presents a list of the parameters entered by the user and allows
any given parameter to be modified, subsequently re-saving the data and
again presenting menu choices for transmission to the host, further
update, and creation.
After creation and validation of search specifications and approval of the
final specification by the buyer, such specification is transmitted via
telecommunications links 20 to host system 200 for application to the
database. After database search, results are prepared as previously
described and are transmitted or mailed back to the potential buyer for
his use.
A final component of system 10 is seller system 500, which comprises
preparation of a property specification 510. Such a property specification
contains the same data which is interrogated by a potential buyer, but
such data is definite and not in ranged numerical form. This is obvious
since a seller generally only has a fixed number of, for instance bedrooms
in his house, and would not necessarily specify that he has a house
containing 2 to 4 bedrooms. After preparation of a seller specification
for a property, that information is transmitted to host system 200 and
used in database maintenance for entry of new property information into
the database. After entry, such new property information becomes available
for search by all buyers.
Referring now to FIG. 4, there is shown a detailed flow chart for Create
Specification Procedure 110, which is part of remote system 100. Create
Specification Procedure 110 begins at the block labeled start 112 and
proceeds to initialize the various memory locations and variables required
for its own internal processing at block 114. After initialization, the
procedure obtains a new center and radius (location information), and
price and size information from the user at 116. Obtaining location
information will be described more fully hereinafter. After locating a
desired search boundary, the system prompts for and receives input
regarding various specifications of a property at 118. Such specifications
include ranges for price, lot size (in minimum/maximum indicators), number
of bedrooms, and other numerical data, as well as menu selections for home
style, sewage system, roof type, and other such housing elements. After
receiving and validating all such information, a specification file
labeled SRPROP.DAT is written to a mass storage device for saving until
future processing can commence at 120. Finally, the file so written is
transmitted to host system 200 at block 122 and processing to create a
property stops at stop block 124. Block 122 is depicted on FIG. 2 as block
150, "transmit buyer's search file to host."
Referring now to FIG. 5, there is shown a more detailed view of procedures
required for obtaining new center and radius for property location
purposes shown as block 116 on FIG. 4. The procedures for obtaining a new
radius and center depend upon the creation of a scaled map (shown in FIGS.
3A,B) of the target area over which the database contains properties. This
map is generated on a display screen for use by the user. Procedure 116
begins at start block 602 and initializing its own variables in order to
begin processing. Such variables are local in scope and do not interfere
with initialization processing conducted by the calling routine at 114.
Control travels from start block 602 to block 604, where it is seen that
the variables are initialized. After the variables are initialized, the
world coordinates are set to their maximum values in block 606. Next, the
points file must be read into memory from the downloaded points file
sitting in the user's disk storage medium, as shown in block 608.
Control then proceeds to decision block 610, where it is determined whether
the user has completed his location boundary selection. If the user has
completed this selection, control proceeds to block 636, where it is shown
that the center and radius coordinates for the map are changed to the new
center and radius coordinates, just selected. Then, the data values
corresponding to the min and max indicators displayed on the screen are
saved to a disk file. Then the procedure stops at block 640. If the user
has not completed his boundary location selection, processing proceeds
from decision block 610 to block 612, where the last selected (most
current) world coordinates are retrieved from memory. These world
coordinates are then used in block 614 to redisplay the map through the
fixed viewport. The points file is then drawn, as shown in block 616. The
min/max indicators, which are displayed on screen, are set in block 617.
In decision block 618, it is determined whether the min/max indicators have
changed. If they have, the points file is erased in block 622. A "filter"
is used to eliminate points not within the limits of the min/max
indicators set in block 617. In this way, when control leaves block 620 to
block 616, only the new points within the set min/max indicators will be
redrawn. If it is determined at decision block 618 that the min/max
indicators have not been changed, control proceeds to decision block 624.
At decision block 624, an evaluation of the variable "DONE" is performed.
If DONE is equal to 0, this is indicative of the fact that the user wishes
to zoom the display downward, that is, obtain a more detailed view of a
smaller area of the map, and zoom down procedure 628, described more fully
hereinafter, is executed. In the event that done is not equal to 0,
evaluation 626 checks whether done is equal to 2. If it is, this is an
indication that the user wishes to zoom up, that is, view a larger area of
the map with correspondingly less detail, also described hereinafter. In
the event that done is not equal to 0 or 2 as determined in decisions 624
and 626, processing continues by looping to execute decision 610 to
determine whether the user has indicated that he is finished with the
property location selection procedure. If the user is finished, as
indicated at decision 610, the new center and radius of the selected
region are stored in variables indicative of the center CX and CY and
indicative of the radius RAD and processing terminates at stop operation
640.
Operations 628 zoom-down and 630 zoom-up are depicted as a general
procedure type in FIG. 6 as zoom view system 400. Processing begins at
start block 410 and proceeds through a local initialization of variables
at block 412.
After variable initialization, actual key strokes and locator position are
monitored by the program so that the initialized position variable can be
incremented or decremented to change the size or location of the circle or
window box. All corresponding variables that are associated with the
center locations are updated with these incremental values.
In the specific case of operation of the remote system on an IBM personal
computer. Various special keys located on the cursor key pad are
indicative of desired functionality within the zooming procedures. For
instance the plus (+) symbol key is indicative of the users desiring a
zoom-out operation while the minus (-) symbol key is indicative of the
users desiring to zoom-in the display. The cursor keys, left arrow, right
arrow, up arrow, and down arrow, move the center location of the viewing
selection region (whether a rectangle or a circle) in directions
corresponding to north, south, east, and west. The page down (PgDn) key
actually executes a selected zoom by changing the world coordinate system
to match the view selector. The page up (PgUp) key resets the world
coordinate system to its maximum, thus zooming out. After the selection of
zoom mode and function, the bounds of the region which is to be visible on
the screen, are calculated at operation 420. Decision 422 indicates
whether the user has attempted to move the window box past the bounds of
the viewport. If such an attempt has been determined at decision 422,
operation 424 resets the incremental step value applied to the location
variable to 0 to prevent further movement of the window box. Processing
then loops and continues at scan for cursor key operation 414.
In the special case of the actuation of the page down (PgDn) key, detected
in operations 416 and 418, and compared for in decision 419, the
indication that the user is satisfied with the new coordinates of the
window box results in operation 426 wherein the global coordinates are
reset to the parameters defined for the new window box. Processing then
terminates at stop operation 428.
Close and transmit operation 122 of system 110 is detailed more fully in
FIG. 7 which depicts system 122, prepare to transmit search file to host.
FIG. 7 depicts the preparation of the search file for transmission which
commences op | | |
