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What is claimed is:
1. A method of producing an animation having a series of three dimensional
road drawings to be watched from a driver's seat of a vehicle during a
travel between two predetermined positions in a road map, said three
dimensional road drawings being formed on the basis of road data obtained
through three dimensional computer graphics, and said road data being
indicative of roads shown in said animation, comprising the steps of:
providing travel route data indicative of a travel route between said
predetermined positions, and storing road map data including node data
indicative of nodes formed by intersections, corners and ends of roads,
link data indicative of links each connecting two of said nodes to define
a road segment, and road width data indicative of widths of said road
segment;
selecting the road map data covering said travel route based on the
provided travel route data;
calculating the road data forming the series of three dimensional road
drawings on the basis of the node and link data of the selected road map
data to produce said animation having the series of three dimensional
drawings; and
displaying said animation on a screen of a display.
2. A method as set forth in claim 1, wherein said travel route data include
travel speed data indicative of the travel speed of said vehicle in said
animation, said method further comprising the step of determining the
advance speed of said animation on the basis of said travel speed data.
3. A method of producing an animation having a series of three dimensional
road drawings to be watched from a drivers seat of a vehicle during a
travel between two predetermine positions in a road map, said three
dimensional road drawings being formed on the basis of road data and
background data obtained through three dimensional computer graphics, and
said road data and said background data being indicative of roads and
backgrounds, respectively, shown in said animation, comprising the steps
of:
providing travel route data indicative of travel route between said
predetermined positions, and storing road map data including node data
indicative of nodes formed by intersections, corners and ends of roads,
link data indicative of links each connecting two of said nodes to define
a road segment and road width data indicative of widths of said road
segments, generating random numbers;
selecting the road map data covering said travel route based on said travel
route data;
calculating the road data forming the series of three dimensional road
drawings on the basis of the node and link data of the selected road map
data to produce said animation having the series of three dimensional
drawings;
calculating said background data on the basis of the generated random
numbers to produce said animation in such a manner that said backgrounds
are three-dimensionally shown in said three dimensional road drawings; and
displaying said animation on a screen of a display.
4. A method as set forth in claim 3, wherein said travel route data include
travel speed data indicative of the travel speed of said vehicle in said
animation, said method further comprising the step of determining the
advance speed of said animation on the basis of said travel speed data.
5. A method as set forth in claim 3, wherein said background drawing data
include architecture data indicative of architectures, traffic light data
indicative of traffic lights, road sign data indicative of road signs,
guardrail data indicative of guardrails and, tree and shrub data
indicative of trees and shrubs.
6. An apparatus for producing an animation having a series of
three-dimensional road drawings to be watched from a driver's seat of a
vehicle during a travel from the current position of said vehicle to a
destination, said three-dimensional road drawings being formed on the
basis of road data and background data obtained through three-dimensional
computer graphics, and said road data and said background data being
indicative of roads and background, respectively, shown in said animation,
comprising:
vehicle position detecting means for detecting the current position of said
vehicle;
optimum travel route data calculating means for calculating optimum travel
route data indicative of an optimum travel route between the current
position of said vehicle and said destination;
road map data storing means for storing road map data to be referred to
during said travel on said optimum travel route;
road map data selecting means for selecting from said road map data storing
means the road map data covering said optimum travel route;
road data calculating means for calculating the road data forming the
series of three-dimensional road drawings on the basis of the node and
link data of the selected road map data to produce said animation having
the series of three-dimensional road drawings;
background data calculating means for calculating said background data to
produce said animation in such a manner that said backgrounds are
three-dimensionally shown in said three-dimensional road drawings; and
animation displaying means for displaying the produced animation.
7. An apparatus as set forth in claim 6, further comprising random number
generating means for generating random numbers, said background data being
calculated by said background data calculating means on the basis of said
generated random numbers and including architecture data indicative of
architectures, traffic light data indicative of traffic lights, road sign
data indicative of road signs, guardrail data indicative of guardrails,
and tree and shrub data indicative of trees and shrubs,
wherein said road map data stored in said road map storing means include
node data indicative of nodes formed by intersections, corners and ends of
roads, link data indicative of links each connecting two of said nodes to
define a road segment, and road width data indicative of the widths of
said road segments.
8. An apparatus as set forth in claim 6, further comprising:
background element data storing means for storing background element data
including architecture data indicative of architectures, traffic light
data indicative of traffic lights, road sign data indicative of road
signs, guardrail data indicative of guardrails, tree and shrub data
indicative of trees and shrubs, and geographical feature data indicative
of geographical features, said background element data covering the whole
area defined by said road map data stored in said road map data storing
means; and
background element data selecting means for selecting from background
element data storing means background element data covering said optimum
travel route, said background data being calculated by said background
data calculating means on the basis of said selected background element
data,
wherein said road map data stored in said road data storing means include
node data indicative of nodes formed by intersections, corners and ends of
roads, link data indicative of links each connecting two of said nodes to
define a road segment, and road width data indicative of the widths of
said road segments.
9. An apparatus as set forth in claim 6, wherein said animation displaying
means opens a window on its own screen showing said animation and displays
said optimum travel route, the current position of said vehicle, and said
road map covering the current position of said vehicle in said window in
such a manner that said optimum travel route and the current position of
said vehicle are overlaid upon said road map.
10. An apparatus as set forth in claim 6, wherein said animation displaying
means opens a window showing said animation on its own screen and displays
said optimum travel route, the current position of said vehicle, and said
road map covering the current position of said vehicle on said screen in
such a manner that said optimum travel route and the current position of
said vehicle are overlaid upon said road map.
11. An apparatus as set forth in claim 6, wherein based on the current
position of said vehicle detected by said vehicle position detecting
means, said animation displaying means displays said animation while said
vehicle travels from a first position approaching toward each of the
intersections on said optimum travel route to a second position departing
from the intersection, and subsequently displays said optimum travel
route, the current position of said vehicle, and the road map covering the
current position of said vehicle while said vehicle travels from said
second position to a third position approaching toward the next
intersection in such a manner that said optimum travel route and the
current position of said vehicle are overlaid upon a road map.
12. An apparatus as set forth in claim 6, further comprising advance
direction indicating means for phonetically indicating an advance
direction of said vehicle at each of the intersections on the basis of
said travel route data before said vehicle reaches the intersection. |
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Claims |
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Description |
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FIELD OF THE INVENTION
The present invention relates to a method of and an apparatus for producing
an animation having a series of road drawings to be watched from a
driver's seat. The road drawings are obtained on the basis of road map
data through three-dimensional computer graphics.
DESCRIPTION OF THE PRIOR ART
There have been so far proposed a method of and an apparatus for producing
an animation having a series of road drawings to be watched from a
driver's seat of a vehicle. If such an animation is displayed on the
screen of a display unit placed in a playing room, the animation is useful
for a driving simulation in the room. For example, the animation can be
produced by executing a computer graphics software.
When, however, the animation is produced by executing programs of such a
computer graphics software, it is necessary that an animator should
imaginatively derive road data (including data indicative of a pattern of
a travel route, data indicative of the shapes of the roads forming the
travel route, and data indicative of the widths of the roads) indicative
of the road drawings forming the animation, thereby having the animator
extremely expend his labor and time. In addition, the variety of the
travel route pattern is so restricted that the animation loses its
popularity soon.
The present invention has been made to overcome the foregoing problems in
the prior art, and a first object of the present invention is to provide a
method of producing an animation having a series of road drawings showing
roads which are in existence.
It is a second object of the present invention to provide an apparatus
capable of displaying the animation in such a manner that the animation is
synchronous with the actual vehicle travel.
SUMMARY OF THE INVENTION
The foregoing first object of the present invention can be achieved by
providing a method of producing an animation having a series of road
drawings to be watched from a driver's seat of a vehicle during a travel
between two predetermined positions in a road map, the road drawings being
formed on the basis of road data obtained through three-dimensional
computer graphics, and the road data being indicative of roads shown in
the animation, comprising the steps of: preparing travel route data
providing means for providing travel route data indicative of a travel
route between the predetermined positions, and road map data storing means
for storing road map data including node data indicative of nodes formed
by intersections, corners and ends of roads, link data indicative of links
each connecting two of the nodes to define a road segment, and road width
data indicative of the widths of the road segments, selecting from the
road map data storing means the road map data covering the travel route
based on the provided travel route data, and calculating the road data on
the basis of the selected road map data to produce the animation in such a
manner that the roads are three-dimensionally shown in the road drawings.
In addition, the foregoing first object of the present invention can be
achieved by providing a method of producing an animation having a series
of road drawings to be watched from a driver's seat of a vehicle during a
travel between two predetermined positions in a road map, the road
drawings being formed on the basis of road data and background data
obtained through three-dimensional computer graphics, and the road data
and the background data being indicative of roads and backgrounds,
respectively, shown in the animation, comprising the steps of: preparing
travel route data providing means for providing travel route data
indicative of a travel route between the predetermined positions, road map
data storing means for storing road map data including node data
indicative of nodes formed by intersections, corners and ends of roads,
link data indicative of links each connecting two of the nodes to define a
road segment and road width data indicative of the widths of the road
segments, and random number generating means for generating random
numbers, selecting from the road map data storing means the road map data
covering the travel route based on the travel route data, calculating the
road data on the basis of the selected road map data to produce the
animation in such a manner that the roads are three-dimensionally shown in
the road drawings, and calculating the background data on the basis of the
generated random numbers to produce the animation in such a manner that
the backgrounds are three-dimensionally shown in the road drawings.
The foregoing second object of the present invention can be achieved by
providing an apparatus for producing an animation having a series of road
drawings to be watched from a driver's seat of a vehicle during a travel
from the current position of the vehicle to a destination, the road
drawings being formed on the basis of road data and background data
obtained through three-dimensional computer graphics, and the road data
and the background data being indicative of roads and backgrounds,
respectively, shown in the animation, comprising: vehicle position
detecting means for detecting the current position of the vehicle, optimum
travel route data calculating means for calculating optimum travel route
data indicative of an optimum travel route between the current position of
the vehicle and the destination, road map data storing means for storing
road map data to be referred to during the travel on the optimum travel
route, road map data selecting means for selecting from the road map data
storing means the road map data covering the optimum travel route, road
data calculating means fop calculating the road data on the basis of the
selected road map data to produce the animation in such a manner that the
roads are three-dimensionally shown in the road drawings, background data
calculating means fop calculating the background data to produce the
animation in such a manner that the backgrounds are three-dimensionally
shown in the road drawings, and animation displaying means for displaying
the produced animation.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of a method of and an apparatus for producing
an animation having a series of road drawings to be watched from a
driver's seat of a vehicle in accordance with the present invention will
be more clearly understood from the following description take in
conjunction with the accompanying drawings in which:
FIG. 1 is a schematic block diagram of an animation producing system
employing an animation producing method according to the present
invention;
FIGS. 2(a) to 2(c) are explanatory illustrations showing processes of
forming a realistic road image from nodes and links;
FIGS. 3(a) and 3(b) are explanatory illustrations showing processes of
forming a realistic road image after the processes shown in FIG. 2(c);
FIGS. 4(a) to 4(c) are explanatory illustrations showing road profile
smoothing processes in the case that two Links extend from one node in
different directions;
FIGS. 5(a) to 5(c) are explanatory illustrations showing intersection
profile smoothing processes in the case that links representing different
roads in width extend from one node;
FIGS. 6(a) and 6(b) are explanatory illustrations showing processes of
smoothing an intersection profile and sidewalk profiles by curved lines
and the like.
FIGS. 7(a) and 7(b) are explanatory illustrations showing processes of
positioning an architecture on the basis of the random numbers;
FIGS. 8(a) to 8(e) are explanatory illustrations showing processes of
eliminating an architecture overlapped with the previous architecture.
FIG. 9 is an explanatory illustration showing the travel position while the
vehicle passing through an intersection:
FIG. 10 is a diagram showing the vehicle speed in the animation while the
vehicle passes through intersections and corners;
FIG. 11 is a diagram showing a road map defined by the links and nodes;
FIG. 12 is a diagram showing a road drawings partially forming the
animation;
FIG. 13 is a block diagram showing a navigation apparatus comprising an
animation producing apparatus according to the present invention; and
FIG. 14 is a block diagram showing the controller shown in FIG. 13.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of an animation producing system adopting an animation
producing method according to the present invention will be hereinlater
described with reference to FIGS. 1 to 12 of the drawings.
The animation produced by the animation producing system has a series of
road drawings to be watched from a driver's seat of a vehicle during a
travel between two predetermined positions in a road map. The road
drawings are formed on the basis of road data and background data obtained
through three-dimensional computer graphics. The road data and the
background data are indicative of roads and backgrounds, respectively,
shown in the animation, and integrally forms road drawing data indicative
of the road drawings.
FIG. 1 is a block diagram showing the animation producing system which
comprises a road map data base device 1, a navigation apparatus 2, a
flexible disk 3, a calculator 4, road drawing forming equipment 5, a video
tape recorder (hereinlater simply referred to as "VTR") 6, and an
animation data base device 7.
The flexible disk 3 stores and provides travel route data indicative of a
travel route between the aforementioned predetermined positions, i.e., to
be traveled by the vehicle. Additionally, the travel route data includes
travel speed data indicative of the travel speed of the vehicle in the
animation. The advance speed of the animation is determined in such a
manner as to be varied in response to the travel speed of the vehicle.
The road map data base device 1 such as for example a CD-ROM (Compact Disc
of Read Only Memory) stores road map data formed by the whole country map
data base providing maps drawn to a scale of for example 1/2,500. The road
map data are indicative of road maps formed by a plurality of nodes and a
plurality of links. In other words, the road map data include node data
indicative of nodes formed by intersections, corners and ends of roads,
link data indicative of links each connecting two of the nodes to define a
road segment and road width data indicative of the widths of the road
segments. The positions of the nodes are represented by coordinates. Each
of the links is to be represented as a vector defined by coordinates of
two nodes connected by the link.
The navigation apparatus 2 is adapted to generate leading indication data
indicative of the travel route, the current position of the vehicle and
the advance direction in which the vehicle is to advance at each of the
intersections on the travel route. Based on the leading indication data,
the travel route, the current position and the advance direction of the
vehicle are displayed as the navigational guidance described hereinafter
on a screen of a display unit not shown. In addition, the leading
indication data are used for phonetically indicating the advance direction
when the vehicle approaches toward each of the intersections.
A conventional navigation apparatus comprises a position detecting
equipment for detecting the current position of the vehicle, and a travel
route calculating equipment for calculating travel route data indicative
of the optimum travel route. The vehicle position detecting equipment
comprises a direction sensor for detecting the travel direction of the
vehicle and a speed sensor for detecting the travel speed of the vehicle.
The current position of the vehicle is derived on the basis of the outputs
of the direction sensor and the speed sensor. Additionally, the
conventional navigation apparatus reads out the road map data covering the
current position of the vehicle from a map data base device so as to have
a display unit displaying the current position of the vehicle and the road
map covering the current position of the vehicle in such a manner that the
current position of the vehicle is overlaid upon the road map. In the
conventional navigation apparatus, therefore, the foregoing leading
indication data are calculated on the basis of the detected current
position of the vehicle and the calculated optimum travel route. Such a
conventional navigation apparatus is generally known and disclosed in, for
example, Japanese patent laid-open publication No. 2-6713.
In the present embodiment, however, the navigation apparatus 2 is designed
to input from, for example, the calculator 4 the position data indicative
of the provisional current position of the vehicle and the travel route
data provided from the flexible disk 3 on the assumption that the vehicle
is traveling the travel route based on the provided travel route data. The
navigation apparatus 2 calculates the leading indication data on the basis
of the position data indicative of the provisional current position the
vehicle and the travel route data provided from the flexible disk 3.
The calculator 4 is electrically connected to the road map data base device
1, the navigation apparatus 2, the flexible disk 3, the road drawing
forming equipment 5 and the animation data base device 7, and functions as
a random number generator. In the calculator 4, the road data and the
background data are calculated by, for example, executing programs of a
three-dimensional computer graphics software placed on the market.
The processes of producing the animation will be described hereinafter.
First, the road map data covering the travel route derived from the
flexible disk 3 are selected and read out by the calculator 4 from the
road map data base device 1. Based on the selected road map data, the road
data are calculated by the calculator 4 in such a manner that the roads
are three-dimensionally shown in the road drawings. Then, the background
data are calculated by the calculator 4 on the basis of the random numbers
in such a manner that the backgrounds are three-dimensionally shown in the
road drawings.
The road drawing data formed by the road data and the background data
calculated by the calculator 4 are fed to the road drawing forming
equipment 5 or the animation data base device 7.
When the road drawing data including the road data and the background data
calculated by the calculator 4 are processed by the road drawing forming
equipment 5, the series of road drawings are generated, thereby making it
possible to produce the animation in the NTSC (National Television System
Committee) formula. The produced animation is recorded in the VTR 6.
The processes of calculating the aforementioned road data will be more
specifically described hereinafter.
The road data are calculated on the basis of the foregoing selected road
map data in such a manner that the road data are indicative of realistic
road images each having appropriate width. If necessary, the road data are
further calculated in such a manner that sidewalks are added to the
realistic road image.
FIGS. 2 and 3 are plan views representing the roads for explaining the
processes of forming the realistic road image. FIG. 2(a) shows the node N1
indicative of an intersection, and four links (including the link L1)
extending from the node N1 and indicative of four road segments. The
widths W of the road segments are determined on the basis of the
aforementioned road width data, thereby making it possible to derive the
profiles of the roads segments as shown in FIG. 2(b). The unnecessary
lines and dots shown in FIG. 2(b) are eliminated in order to derive the
realistic road image shown in FIG. 2(c). Additionally, sidewalks having
widths t are added to the realistic road image as shown in FIG. 3(a), and
then pedestrian crossings and center lines are also added to the realistic
road image as shown in FIG. 3(b).
If two links extend from one node in different directions, i.e., the links
L2 and L3 extend from the node N2 as shown in FIG. 4(a), the realistic
road image derived on the basis of the links L2 and L3 and the node N2 is
shown in FIG. 4(b). The road profile shown in FIG. 4(b) however is
unnatural in comparison with the profile of the actual road, since the
road profile shown in FIG. 4(b) is formed by merely straight lines. In
this case, a smoothing process is carried out in order to smooth the
corners of the roads. As a result, the profile of the corner of the road
is defined by curved lines such as circular arcs as shown in FIG. 4(c).
If a plurality of links representing roads different in width extend from
one node, i.e., the links L4 and L5 extend from the node N3 as shown in
FIGS. 5(a) and 5(b), the realistic road image is formed in such a manner
that the roads formed on the basis of the links L4 and L5 are connected to
each other by means of a road segment having a taper profile portion as
shown in FIGS. 5(c).
In the processes of forming the realistic road image representing an
intersection, the aforementioned smoothing process are carried out in
order to smoothly connect the lines forming the road profiles, since the
realistic road image shown in FIG. 6(a) is unnatural in comparison with
the actual intersection. In addition, another smoothing process is carried
out in order to cut the corner of each of the blocks enclosed by
sidewalks, respectively. After the foregoing smoothing processes, the
realistic road image shown in FIG. 6(b) are derived.
When the sidewalks are added to the realistic road image, the road data are
calculated in such a manner that each of the sidewalks has a width of 1.5
meters and is flush with the road or in such a manner that each of the
sidewalks has a width of 3 meters and has sidewalk surface higher than the
road surface by 20 centimeters.
The processes of calculating the background data on the basis of the random
numbers will be more specifically described hereinlater.
The background data includes architecture data indicative of architectures
such as buildings and dwelling houses, traffic light data indicative of
traffic lights, road sign data indicative of road signs, guardrail data
indicative of guardrails and, tree and shrub data indicative of trees and
shrubs.
If the background comprises the images of the buildings, the width, the
depth and the height of each of the buildings can be varied within
predetermined ranges, respectively, each having a predetermined standard
value and defined by a predetermined maximum value and a predetermined
minimum value. The width, the depth and the height of each of the
buildings are determined on the basis of the random numbers in such a
manner as to be within the predetermined ranges, respectively. On the
other hand, the positions of the buildings are determined in such a manner
that each of the buildings is positioned along the road. In addition, the
number of the buildings positioned along one road are determined in
response to the length of the link forming the road. The architecture data
include dwelling house data indicative of several kinds of the dwelling
house. The dwelling houses are similarly positioned along the road, and
the number of each of the dwelling houses are similarly determined in
response to the length of the link forming the road.
If, for example, the length of the link is less than 120 meters, there is
no architecture positioned along the road defined the link. If the length
of the link exceeds 120 meters, at least one architecture is positioned
along the roads. In FIG. 7(a), the width A of the building is determined
on the basis of the random numbers in such a manner as to be represented
by an integer in meters and to be within a range from 20 meters to the
length of the link L6. The depth B of the building is determined on the
basis of the random numbers in such a manner as to be represented by an
integer in meters and to be within a range from 20 to 50 meters. The
height of the building is determined on the basis of the random numbers in
such a manner as to be represented by an integer in meters and to be
within a range from 30 to 80 meters. The color used for painting the
building is selected from predetermined eight colors on the basis of the
random numbers. The design of building is selected from predetermined two
designs on the basis of the random numbers.
If the architecture is positioned along the road defined by the link L6
shown in FIG. 7(a) in the neighborhood of the intersection at which the
road intersects with another road at a right angle, the distance M between
the architecture and the road defined by the link L6, and the distance M
between the architecture and the alternate long and short dash line
passing the end of the link L6 are determined, for example, to be 10
meters. Preferably, the distances M may exceed half of the width of the
road defined by the link L6.
If, however, the architecture is positioned along the road defined by the
link L6 shown in FIG. 7(b) in the neighborhood of the intersection at
which the road intersects with another road at the acute angle .theta.,
the aforementioned determination of the distances M sometimes results in
the fact that the image of the building is overlapped with the image of
the another road. For this reason, it is necessary that the distance
between the architecture and the alternate long and short dash line
passing the end of the link L6 should be represented by (M+N) instead of
M. The distance N, for example, is determined by a formula represented as
follows.
N={M+B+(W/2)}/tan .theta.
When, additionally, a plurality of architectures are positioned in the road
image having a plurality of corners within a narrow area, it is necessary
that attention should be paid to the overlap of the architectures. If, for
example, the architectures are positioned along the cranked road defined
by a plurality of links including the link L7 as shown in FIG. 8(a), the
angles .alpha.1 and .alpha.2 shown in FIG. 8(b) between the link L7 and
the adjoining links are calculated, and then the size of the architecture
shown in FIG. 8(c) is determined on the basis of the random numbers in
view of the calculated angles .alpha.1 and .alpha.2. As shown in FIG.
8(d), two architectures are positioned in the neighborhood of the end of
the link L7 so as to be opposite to each other through the road defined
the link L7 under the condition that the aforementioned distances M are
equal to 0. The next architectures are similarly positioned in the
neighborhood of the end of the next link as shown in FIG. 8(e). If,
however, one of the next architectures and one of the previous
architectures are overlapped with each other in part, the next
architecture is eliminated from the road image as shown in FIG. 8(e).
The traffic lights for the vehicles are positioned at the specified
intersections and each periodically indicates red, amber and green. The
traffic lights for the pedestrians are positioned at the pedestrian
crossing in the neighborhood of the specified intersections and each
periodically indicates red and green.
The road signs are positioned at the specified intersections. The trees and
shrubs, and the guardrails are positioned along the specified roads. The
sky of the background are painted in sky blue. The color of the open space
between the architectures in the background is predetermined.
The height of the view point in the animation is similar to that (for
example 1.2 meters) of the eyes of the driver on the driver's seat. If the
width of the vehicle is 1.6 meters, the view point in the animation is
positioned at the right side of the center of the vehicle in such a manner
as to be remote from the center by 0.4 meters. The angles in the view
point of the animation between two planes defining the horizontal visual
field and between two planes defining the vertical visual field are 140
degrees and 100 degrees, respectively. The vehicle in the animation
travels on the center of the left lane of the center line as shown in FIG.
9. As will be understood from the diagram shown in FIG. 10, the vehicle in
the animation slows down during a travel of a predetermined distance a
before a rapid variation of the advance direction of the vehicle. On the
other hand, the vehicle in the animation speeds up during a travel of the
predetermined distance a after the rapid variation of the advance
direction of the vehicle.
According to the aforementioned processes, the road data and background
data are calculated thorough the three-dimensional computer graphics,
thereby making it possible to produce the animation having the series of
the road drawings to be watched from the driver's seat.
Next, an example of the animation will be explained. If a certain area, for
example, Edogawa-ku in Japan is selected, a road map shown in FIG. 11 and
formed by the nodes and the links is derived from the road map data base
device 1. If the vehicle is to travel from a position D to a position E,
the travel route data indicative of the travel route (referred to arrows
in FIG. 11) between the positions D and E are fed to the calculator 4 in
order to calculate the road data and the background data on the basis of
the travel route data by the foregoing processes, thereby making it
possible to produce the animation having the series of road drawings to be
watched from the driver's seat. One of the road drawings is shown in FIG.
12 and represents a street scene seen through the front window by the eyes
of the driver on the driver's seat before the vehicle reaches the
intersection defined by the position C in FIG. 11. The road drawing shown
in FIG. 12 includes center lines, sidewalks and pedestrian crossings. The
corners of the intersection are defined by curved lines in the road
drawing. Additionally, the road drawing includes the traffic lights, the
building and the tree positioned in the neighborhood of the intersection.
The display unit opens first and second windows on its own screen showing
the road drawing and displays the navigational guidance derived from the
navigation apparatus 2 so as to show the travel road and the advance
direction of the vehicle to the driver. More specifically, the first
window shows a road map area similar to the rectangular area R covering
the position C as shown in FIG. 11 and indicates by a predetermined mark
the current position of the vehicle on the road map. As shown in FIG. 12,
the second window opened in the first window indicates the advance
direction in which the vehicle is to advance at the intersection. The
color of each of the roads forming the travel route may be determined in
such a manner as to be different from that of the other roads in the road
map. The buildings, the traffic lights and the like are not shown in the
navigational guidance. The navigational guidance is shown in the first and
second windows in such a manner that the vehicle advances in the
perpendicular direction in FIG. 12. However, the north in the road map may
correspond to the upper part of the windows.
After the advance direction is indicated in the second window, the vehicle
is to turn according to the indicated advance direction, for examp | | |
