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BACKGROUND OF THE INVENTION
This invention relates to a system which displays planar map data and cubic
scene data on a graphic display, conducts normally a sight-seeing guide
and shows the way, while it performs evacuation guidance in case of
emergency. More particularly, the present invention relates to a method
which improves operability of the system by a user.
The present invention relates also to a system for displaying a window
having a three-dimensional shape in a scene displayed in a graphic
display, and particularly to a method for improving efficiency in
operating data displayed in a display and improving further visuality.
The prior art from the first aspect includes the following systems.
Systems for displaying a scene from a vector map and for retrieving a route
on a map and displaying multi-media information such as a photo of a
landscape near the route are described in "Towards Higher Utilization of
Graphic Image Media" (1990, pages 49 to 54) of Papers of Functional
Graphic Data Symposium and in "Graphics and CAD 49-3" (1991, pages 1 to 8)
of Research Documents of Data Processing Society. Graphic image display,
interface and systems in accomplishing virtual reality display of scene
data are described in Documents of Servomechanism Association (1990, pages
11 to 14) and in "Graphics and CAD 49-8" (1991, pages 1 to 8) of Research
Documents of Data Processing Society.
However, the prior art based on the first aspect is primarily directed to
the conversion of a planar map to a cubic scene and to its display, but
does not disclose a system for accomplishing simultaneously the
characterizing features of both of them. That is, high visuality of a
topological arrangement relation between figures in the case of the planar
map and sensorial easiness in the case of the cubic map are provided on
one system. As to the virtual reality system, a report has been made on
the movement of an object in the virtual world displayed graphically, a
contact method by a user to the object using a head mount type sensor
device or a glove type sensor device, and display of its reaction, but no
method has been reported which generates a new space in the virtual word
expressed by scenes and displays additional attributes in another world in
the virtual world by the use of windows.
As the prior art based on the second aspect, a display method of a window
on a display and a method of using the window in computer graphics and
topographic data processing are known as listed below.
Display method:
(1) a method which divides a main data display area from a window display
area;
(2) a method which displays overlappingly the window with the main data
display area. The window display method (1) is the system which secures in
advance another region as a window region 1802 separately from a main data
display region 1801 of a display screen for displaying main data as shown
in FIG. 18, executes data processing in the main data display region 1801
in the interlocking arrangement with the data processing in the window
display region 1802 or preferentially executes data processing in either
of the regions. JP-A-2-165390 displays a map in such a window in order to
determine the visual point of a three-dimensional object and its visual
line, and recognizes the visual point and line in accordance with the way
of watching the map.
The window display method (2) has its feature in that the window area is
displayed inside the display screen of main data. JP-A-1-180343 employs a
window in order to display an enlarged view, and adaptively changes the
size of the window lest a region which is to be enlarged overlaps with the
window display region as shown in FIG. 19. In FIG. 19, reference numeral
1901 denotes a main data display region, reference numeral 1902 denotes a
display region to be enlarged and reference numeral 1903 does a window
display region (display in enlargement).
As to the methods of using the window, there are the following two methods.
(1) a method which displays data in the window; and
(2) a method which regards the window as another world, activates a program
linked with the window, and activates and executes a different program for
each window.
The window using method (1) uses the window as a system which enables a
user to easily watch the data, and JP-A-1-180343 discloses one of such
examples.
The window using method (2) uses the window as a user interface for
developing and executing a plurality of programs on one computer in a
computer system capable of executing multi-task processings.
In the prior art based on the second aspect, the window displaying method
(1) involves the problem that the main data display region becomes small
because the display screen is used after being divided. The window
displaying method (2) does not divide the display screen and has the merit
that the display can be watched easily. However, the shape of the window
is two-dimensional inside the display, and even three-dimensional data are
given to the user as an image obtained by projecting the three-dimensional
data on the two-dimensional window. Accordingly, when an access is made to
the three-dimensional data displayed in the window by the use of a
pointing icon so as to rotate the three-dimensional data having a
complicated shape or to change its size, a complicated interference check
with the data is necessary, and recognition of the visual line and point
is difficult.
As described above, the window shape is two-dimensional in the window using
method (1), and the window using method (2) does not relate to the display
of the data. In this way, the prior art has failed to efficiently
manipulate the three-dimensional data.
SUMMARY OF THE INVENTION
It is a first object of the present invention to provide a system which can
shift and utilize both planar and cubic media without any malaise by
moving the visual point of a user when a visual scene is generated using
map data and can select a medium easily comprehensible to the user, and a
system and method friendly to the user by displaying a rectangular or
parallelepiped window inside the scene and displaying a document, a
figure, an image, etc, inside the window. This system can be utilized also
as a virtual reality system, and is an easy-to-operate visual interface
for the user not using conventional input devices such as keyboards and
mouses.
It is a second object of the present invention to provide a system which
improves efficiency for operating data displayed on a display and
improving further visuality.
According to the first aspect of the present invention, there is provided a
graphic data processing system which comprises means for retrieving vector
map data; means for generating scene data from the retrieved vector map
data; means for projecting and displaying the generated scene data on a
two-dimensional plane determined by position and direction of a visual
point; means for changing the position or direction of the visual point;
and means for selecting a display method which generates the scene data
from the vector map data by the use of the scene data generation means on
the basis of a changed visual point when the visual point is changed from
a vertical direction to a horizontal direction by the use of the visual
point change means, and a display method which displays the vector map
data in place of the scene data on the display means when the visual point
is changed from a horizontal direction to a vertical direction by the use
of the visual point change means.
In other words, when the visual point is directed from above to below, the
image is displayed by the planar map and as the visual point moves towards
the horizontal direction, the three-dimensional scene image is generated
and displayed from the map.
In a more definite embodiment, a pointing system is employed in which an
indication cursor is displayed to display attributes in the scene, and a
ground object such as a building existing in the direction of the
indication cursor is retrieved from the map data in accordance with the
direction of the cursor. Furthermore, a three-dimensional window is
calculated, and is preferentially displayed by effecting interference
check with the ground object in the scene so that media such as figures
and images can be displayed and the display can be made without malaise
from the scene. Since an object having the attributes to be displayed in
the window is sometimes hidden by another ground object, such an object is
retrieved from the map data, the display of the hiding object is changed
from solid display to wire frame display and the object is thus
high-lighted. Furthermore, the objects of the wire frame display are
allowed to pass through without effecting the interference check while the
objects of the solid display are not allowed to pass through by effecting
the interference check, so that the user can utilize the system more
realistically.
Since smooth movement between the planar map and the cubic map is insured
by the movement of the visual point, the user does not lose his sight in
both cases. Display can be made in the forms easily comprehensible to the
user and print output becomes easier.
The three-dimensional window displays the attributes added to the ground
object without any malaise with the scene. Any complicated operations are
not required for selecting the ground object.
Because the execution of the interference check is switched depending on
the difference of the forms of the wire frame display and the solid
display, judgement of permission of the passage is easy, and any malaise
that would otherwise occur due to the switch of the scene during display
can be prevented.
From the second aspect of the present invention, there is provided a
graphic data processing system which comprises a display for displaying
graphic data and means for displaying a three-dimensional window on the
display and also displaying graphic data in the window.
In a more definite embodiment, a three-dimensional parallelepiped window or
windows are disposed in order to display a part of the graphic data
displayed on the display screen or other graphic data, as shown in FIG.
17. Scroll bars, enlargement/scale-down selectors (keys), rods for
rotating the window, rails for moving the window and means for connecting
the movement of each icon with the movement of the three-dimensional
window are added to the window so that the size and position of the window
can be changed by making access to these operation icons without making
direct access to the three-dimensional data inside the window, and along
therewith, enlargement/scale-down, scroll, rotation and movement of the
three-dimensional data can be carried out. The world displayed in the
three-dimensional window is regarded as a different world from the world
displayed outside the window by window management means and a window
management table, and when the pointing icon is contained in the
three-dimensional window, control of the data operation is switched by
switching the control of a computer to the world in the window having
higher priority. At this time, the program associated with the
three-dimensional window, to which control shifts, can be activated.
Scroll, enlargement/scale-down and rotation of the three-dimensional data
can be made by making access to the scroll bars, enlargement/scale-down
selectors and rods added to the three-dimensional window, without the need
of a direct access function to the data having a complicated
three-dimensional shape and displayed inside the three-dimensional window.
The position of the visual point and the direction of the visual line can
be estimated easily from the display position and shape of the window
displayed on the display.
Next, a plurality of worlds the data express can be displayed by the
three-dimensional window. The user can select the world he is interested
in from the relation of inclusion of the pointing icon with the
three-dimensional window. When a plurality of three-dimensional data are
displayed inside mutually different three-dimensional windows, the user
can operate the program associated with the group of data in which he is
interested in particularly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a functional view of a visual guide system according to the
present invention;
FIGS. 2A, B, C are explanatory views showing examples of use of a
conventional guide system;
FIG. 3 is a structural view showing the construction of the visual guide
system;
FIG. 4 is a structural view of a virtual experience system by which a
system user can experience guidance while entering virtually a scene;
FIGS. 5A, B, C are explanatory views wherein the shift between map data and
scene data can be executed smoothly without any malaise by the change of a
starting point;
FIG. 6 is a flowchart showing the algorithm for executing the shift between
a planar map and a cubic map without a malaise;
FIG. 7 is a flowchart showing the algorithm for executing the shift between
the planar map and the cubic map without a malaise;
FIG. 8 is a structural view of the map data;
FIG. 9 is a flowchart showing the algorithm for displaying attribute
information added to ground object data in the scene;
FIG. 10 is a flowchart showing the algorithm for displaying attribute
information added to ground object data in the scene;
FIG. 11 is an explanatory view useful for explaining a retrieval system of
ground object data by beam shot pointing;
FIG. 12 is a management system diagram of scene and attribute data;
FIG. 13 is an explanatory view useful for a system for retrieving other
ground object data hiding the retrieved ground object data;
FIGS. 14A, B are explanatory views showing the display of attribute
information by a definite screen image;
FIGS. 15A, B, C are explanatory views showing that the system effects
guidance by an autonomous operation, through a screen image;
FIG. 16 is an explanatory view showing a screen image when the visual guide
system is used for evacuation guidance in case of emergency;
FIG. 17 is an explanatory view showing an application example of a building
management system of a three-dimensional window system;
FIG. 18 is an explanatory view showing an example of a window display
method according to the prior art;
FIG. 19 is an explanatory view showing a window display method according to
the prior art;
FIG. 20 is a structural view showing an example of a graphic data
processing system;
FIG. 21 is a structural view showing another example of a graphic data
processing system;
FIG. 22 is a structural view showing three-dimensional window functions;
FIG. 23 is an explanatory view showing the relation of three coordinate
systems necessary for the three-dimensional window and graphic data;
FIG. 24 is a flowchart showing the flow of a three-dimensional window;
FIG. 25 is an explanatory view showing a display image of a
three-dimensional window and a window operation icon;
FIG. 26 is a table showing the content of a three-dimensional window
management table;
FIG. 27 is an explanatory view showing an application of the
three-dimensional window system to a medical CT system; and
FIG. 28 is an explanatory view showing an application of the
three-dimensional window system to numeric value simulation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The first embodiment of the present invention will be explained with
reference to FIGS. 1 to 16.
In a conventional guide system using map data shown in FIG. 2(a), a map is
displayed on a graphic display, a route from the present position to the
destination through a relay point is retrieved by inputting the present
position, the relay point and the destination. In other words, this guide
system is mainly directed to display the route on the map or to print out
the retrieved route in superposition with the map as shown in FIG. 2(b).
Alternatively, a document added to ground object data such as surrounding
buildings and multi-media data such as a graphic image along the route
obtained by calculation or a preset route is submitted to a user by
display means such as a window, as shown in FIG. 2(c). In such a system,
however, the map data is displayed merely as the background. Therefore, it
is difficult to confirm the actual present position by the map alone, and
when the route is displayed, too, it is rather difficult to establish a
relation of correspondence to the route which is to be taken in practice.
Since the conventional guide system is mono-functional, it can be used for
limited applications such as a tourist guide, a road guide, and so forth,
and cannot be used for many other purposes. This embodiment provides a
three-dimensional reconstruction method of a map to cope with the former
problem and a multi-purpose method which functions normally as a road
guide system but functions as an evacuation guide system in case of
emergency to cope with the latter problem.
FIG. 3 is a structural view of a multi-purpose visual guide system for
accomplishing the first embodiment of the present invention. A computer
301 is an interface device for the user, and the map data is displayed on
this interface. The map data are vector data which are expressed by
polygonal graphics by a coordinate system. The user inputs a key word for
retrieving map and geographic attributes by the use of an input device
such as a keyboard 302 or a mouse 303 to scroll the map and the scene,
designates the map data and the scene data displayed on the display 309,
and outputs the desired data by the use of a printer 304. A map data
server 305 retrieves the ground object data (attribute data) linked with
the map data and the ground object data displayed on the display 309,
using the keys of the coordinates and the names inputted by the computer
301, and transfers the ground object data to the computer 301 through a
network 308. When the desired map data does not exist in the map data
server 305, access is made to other map data server through a network 307
such as a LAN (Local Area Network) so as to retrieve the necessary map
data. Furthermore, the map data server 305 executes route retrieval and
attribute retrieval using the map data and a simulation such as evacuation
guide. A CG computing server 306 executes processings inherent to computer
graphics (CG) such as beam tracking necessary for display the map
three-plurality of objects, hidden surface removal, etc, and prepares a
scene. At this time, the scene is displayed by solid display.
FIG. 4 shows another system construction for accomplishing the first
embodiment of the present invention. This system does not use the ordinary
display, but enables the user to virtually experience a visual guide. In
this visual experience system, the user 412 can feel as if he were in the
world generated by computer graphics. A binocular display 401 is a head
mount type display comprising sub-displays for the right and left eyes,
and detects also the movement of the head by the use of a magnetic sensor.
A surround headphone 402 is an acoustic device, and can express the
Doppler effect when it is provided with an echo function. A glove type
indication device 403 detects the movement of the fingers and the wrists.
A map server 408 and a CG computing server 309 have the same functions as
those of 305 and 306 in FIG. 3, respectively. Signals of the movement of
the head obtained from the binocular display 401 and signals of the
fingers and wrist obtained from the glove type indication device 403 are
applied to a motion analyzer 407 through a binocular display controller
404 and a pointing device controller 406. Simple background data (base
background data) and data (user motion data) reflecting the motion of the
user are constructed in the motion analyzer 407, and this analyzer 407
generates the motion by reflecting the signals applied thereto on the user
motion data. The data are sent to the CG computing server 409, and sound
data are generated, if more real background data and user motion data are
necessary. The sound data are sent to the binocular display controller 404
and to the surround headphone controller 405 so that the scene is
displayed on the binocular display 401 the user 412 is wearing, and the
sound is generated in the surround headphone 402. Reference numeral 411
denotes a network.
A malaise-free conversion method between the two-dimensional planar map and
the three-dimensional cubic map will be explained using the system shown
in FIG. 3. FIG. 5 shows an image of the flow of the map display.
It will be assumed hereby that the visual point of the user exists in the
horizontal direction relative to the map as shown in FIG. 5(a). Display at
this time is a scene display. The visual point is moved by operating an
indication cursor 501 so that the visual point of the user moves from UP
to DOWN. The scene at this time becomes an image in which the side
surfaces of the ground objects become smaller as shown in FIG. 5(b). When
the visual point moves further, the scene is replaced by the map as shown
in FIG. 5(c). Since conversion of the display modes is effected while the
scene and the map are substantially in superposition, the user never loses
sight of the target.
FIGS. 6 and 7 show the conversion algorithm between the planar map and the
scene as the cubic map. This algorithm will be explained with reference to
the detail of the functions of the system shown in FIGS. 1 and 3. The user
inputs the key for retrieving the map (such as the present position) to
the computer 301 (step 601 in FIG. 6), and the map data server 305
convertes it to code data (latitude, longitude, etc.) by a key input
judgement/encoding unit 101. The map data retrieving unit 105 retrieves
the map corresponding to the code data (step 602). This map data is the
vector data and has a format such as shown in FIG. 8. This format can be
displayed in two types, which can be distinguished by one bit of a type
flag. In the type 1, height data (Z coordinates) is added to each point
and in the type 2, the Z coordinates are added uniformly to the polygon as
a whole which is determined by the rows of the (X, Y) coordinates. The
type 1 is suitable for buildings having complicated shapes and the type 2
is suitable for rectangles such as buildings and the contour line. If the
visual point lies in the horizontal direction at this time (step 603), the
map data retrieved or the map data obtained as a result of simulation
calculation in a simulation/calculation unit 107 (to be later described)
is transferred by the data transfer unit 108 to the CG computing server
306, and a scene data generation unit 111 generates scene data by computer
graphics (step 604). A media selection unit 109 has the function of
selecting display means in accordance with the direction of the visual
point. As to the direction of the visual point, a direction of default is
first set, and a three-dimensional image in this direction is displayed.
To generate the scene data, the scene data generation unit 111 effects
shading by hidden surface removal and beam tracking. The scene data or the
map data thus generated is transferred to the computer 301 and the data
display unit 104 controls display (step 605). By the way, the CG computing
server 306, too, has the data transfer unit 114. The scene data is
projected by the data display unit 104 on the two-dimensional plane
determined by the position and direction of the visual point and is
displayed on the display 309.
Next, to scroll the scene data, the visual point or the visual direction is
changed (step 606). The position of the visual point and its direction are
encoded by the key input judgement unit 102 for the indication cursor or
by the scroll key input judgement unit 103. There are two scrolling
methods. The first is scroll of the scene and the other is scroll of the
planar map. It will be assumed hereby that the visual point is changed in
the horizontal direction when the map is watched by the scene (step 607).
When the angle .theta. between the visual direction and the perpendicular
is within a designated range .vertline..theta..vertline..ltoreq..theta.th
(step 608 in FIG. 7), the media selection unit 109 judges that the display
must be made by the use of the map data, and transfers the map data, while
the map display unit 104 effects display control (step 609). At this time,
.theta.th need not always be 0. When .vertline..theta..vertline..noteq.0,
the visual point and the visual direction can be aligned with the image
existing in the visual field of the user by effecting trapezoidal
correction of the map data and displaying it. Next, it will be assumed
that the visual direction is changed from the perpendicular direction to
the horizontal direction. When the relation
.vertline..theta..vertline.>.theta.th within the designated range of the
visual point at this time (step 610), the media selection unit 109 judges
that the display must be made using the scene data, and converts the map
data to the scene data (steps 611, 614). Visual point change scroll with
the change of the visual point is then executed using the resulting data
(step 612). By the way, the function of each of the data display method
judgement unit 110, interference check unit 112 and window generation unit
113 will be explained later.
In this way, the shift between the planar map and the cubic map can be
carried out smoothly without any malaise. When the display is drastically
changed between the scene display by the visual point in the horizontal
direction and the map by the visual point in the perpendicular direction,
the user is likely to lose sight of the present position and the target,
but the system of this embodiment can avoid such a disadvantage. An output
desired by the user can be obtained even when a print output is obtained.
Next, the guide method using the display data will be explained. One of the
important contents in guidance is retrieval and display of the detailed
data of the ground objects. Two modes of guidance are available. One is a
method which is carried out subjectively by the user and the other is a
method which is executed autonomously by the system. To begin with, the
method which is carried out while the user is watching the scene will be
explained. In other words, the user effects scroll and retrieval and
display of the detailed data while watching the scene displayed
three-dimensionally. Scroll is carried out by inputting the following
seven keys.
1: advance 2: retreat 3: UP movement
4: DOWN movement 5: .theta. (Eulerian angle)
6: .phi. (Eulerian angle) 7: .phi. (Eulerian angle)
To designate the ground object having the detailed data, the indication
cursor 501 such as one shown in FIG. 5(a) is displayed. It is necessary at
this time that the cursor be shaped in such a manner as to have the
retrieving direction easily understood. While scroll is being made, the
ground object is designated to retrieve the attributes as its detailed
data. FIGS. 9 and 10 show the attribute retrieval display algorithm.
First of all, the direction of the indication cursor is so set as to select
the ground object (step 801). Though the ground object data can be
obtained by a Z buffer method in computer graphics, it can also be
detected by the map data as the basic data for scene display. Hence, this
method will be explained. A retrieving line extending from the cursor
position 901 to a position 902 shown in FIG. 11 is set to the direction of
the indication cursor (step 802). While this retrieving line is segmented
into small segments from the starting point (step 804), the ground object
data crossing the line is retrieved. In this case, retrieval can be made
easily if the data has a data structure which divides the data into wire
frame data 1001 of the ground object (which means the graphic data shown
in FIG. 5), plane data 1002 and attribute data 1003 and manages them, as
shown in FIG. 12.
First, crossing with the retrieving line 902 is checked using the (X, Y)
coordinates in the wire frame data. The plane data of the crossing ground
object data is then retrieved by tracing the link 1004. This link tracing
operation corresponds to the search of the ID data common to the wire
frame data 1001 and to the plane data 1002 (see FIG. 12). Crossing of the
retrieving line, to which the height is added, with the plane is checked
(step 805). If any crossing point exists (step 806), the coordinates (X,
Y, Z) value of that point is determined, and a line pattern from the tip
of an indication rod to the cross point is drawn in the display so as to
represent that the ground object is selected (step 807). This can be
obtained easily because the four coordinates of the plane and the two
coordinates of the line are known. In FIG. 11, the ground object data 903
and 904 are the object of check as the applicants of crossing. A change of
a color or a highlight display is employed to stress the selected ground
object (step 808). Hereinafter, such a pointing method of the ground
object will be referred to as "beam shot pointing". The pointing method is
particularly effective in a virtual reality system. For, the indication
cursor is moved in match with the movement of the wrist or fingers without
using the interface such as the keyboard or the mouse in this system.
There is a high possibility that considerable portions of the ground object
data retrieved by beam shot pointing are concealed by other ground object
data. Therefore, the display of the ground objects as the cause of this
concealment is changed from solid display to wire frame display. The
selection of the ground object data as the object of the wire frame
display, too, can be made by the use of the map data. This method is shown
in FIG. 13. It will be assumed hereby that the ground object data 904 is
retrieved in FIG. 11.
A line is drawn from a characterizing point that constitutes the indication
cursor position 1101 and the retrieved ground object 1102, to the cursor
position 1101, and figures existing inside the region encompassed by two
outermost lines 1103, 1104 are retrieved (step 809), and display is made
while erasing the plane data of other ground objects and leaving only the
wire frame (step 810). Since the ground objects 1105 and 1106 correspond
to the figures in FIG. 13, the display is changed to the wire frame
display. To effect such a data display at a high speed, the display can be
accomplished by applying different display attributes to the wire frame
data 1001 and to the data of the plane 1002 and erasing only the plane
data. In this way, the ground object data retrieved by beam shot become
easier to watch. This display is executed by the data display method
judgement unit 110.
Next, the attribute data added to the ground object data are retrieved and
are displayed on the display. The retrieving sequence of the attribute
data is as follows. First, the attribute data 1003 are retrieved by
tracing the link 1005 for the ground object data retrieved by beam shot
pointing (step 811). The following two methods can be used. One is a
method which displays a window of a plane by rectangles and the other is a
method which displays a cubic window by rectangular parallelepipeds. Such
windows are displayed in the displayed world. The two-dimensional
rectangular window is used for displaying the document data, the
two-dimensional graphic data and the image data. The window of the
three-dimensional rectangular parallelepipeds is used for displaying the
three-dimensional figures. The window is displayed in such a manner as not
to completely conceal the selected object. How this region is calculated
is as follows. Now, (X, Y, Z) of the pointed ground object data are passed
through a perspective view conversion formula and are converted to the (X,
Y) coordinates on the display. A circumscribed rectangle to this ground
object is calculated from this (X, Y) data. Horizontal and vertical lines
passing the sides of this circumscribed rectangle are considered to divide
the display region. If the sides of the circumscribed rectangle do not
overlap with the boundary of the display region, the maximum display
screen is divided into nine segments. If one of the sides of the rectangle
overlaps, the number of segments is 6 and if two sides overlap, the number
of segments in 4. | | |
