JP2001027533A - Map display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set a viewpoint altitude on three-dimensional display with superior operability and to change image display smoothly with the operation of changing a viewpoint altitude. SOLUTION: A map display device determines whether a viewpoint altitude changing switch is operated or not (S1) and in the case that it is operated, adds the ratio of change in altitude obtained by multiplying a viewpoint before the change by the ratio of change to a minimum change in altitude (a constant value of change in altitude) to obtain the amount of change in altitude (S2). In the case that the viewpoint altitude changing switch is operated to the side of a rise in altitude, the amount of change in altitude is added to the viewpoint altitude before the change to set a viewpoint altitude (S4). In the case that it is operated to the side of a drop in altitude, the amount of change in altitude is subtracted from the viewpoint altitude before the change to set a viewpoint altitude (S5). The image of a three-dimensional map is drawn on the basis of the set viewpoint altitude.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a map display device for displaying a map three-dimensionally on a screen.

[0002]

For example, in a map display device used in a car navigation device, a map is displayed three-dimensionally on a screen so that a user can intuitively understand the map. Have been done. In some cases, when performing a three-dimensional map display, the viewpoint height can be changed in order to improve the visibility of the map display.
As one example, as shown in FIG. 9A, the user sets the viewpoint height of the bird's-eye view in several predetermined steps (for example, low,
There is a car navigation device configured to be able to select and set from three levels (middle and high).

In general, in a three-dimensional map display in which buildings and the like are three-dimensionally displayed on a screen, if a set viewpoint altitude is low, a road or a building that a user wants to see is a tall building or the like located on the near side. If they are hidden behind and are not displayed, or if the set viewpoint altitude is high, the three-dimensional effect and perspective that can be obtained due to the degree of overlap between buildings and the like may be impaired. These circumstances vary in various ways depending on the buildings and roads displayed on the screen and their arrangement, terrain, map portions desired by the user, and the like. However, in the above-described car navigation device, since the user can select only three viewpoint heights, there are cases where an optimum viewpoint cannot be set according to such various circumstances. Further, when the viewpoint altitude is switched, the screen display changes greatly at a time, so that it is difficult for the user to grasp the correspondence between the screen display before the switch and the screen display after the switch.

On the other hand, as shown in FIG. 9 (b), there is a car navigation system in which the viewpoint altitude can be increased or decreased in a number of steps at a constant altitude. According to this car navigation device, the user can set the viewpoint to a desired altitude according to the circumstances and purpose on the map display described above. However, when the viewpoint is changed from a low altitude to a high altitude, there is an operational inconvenience that the target altitude cannot be easily set even if the user operates a switch or the like to sequentially increase the altitude at a constant altitude. Was. Also, at relatively high viewpoint altitudes, even if the viewpoint altitude is gradually increased or decreased by a constant altitude, the map displayed on the screen does not change much. It was hard to get a down feeling.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and its object is to set a desired viewpoint height with good operability when displaying a three-dimensional map, and to display a screen with a change operation of the viewpoint height. Is to provide a map display device that changes smoothly.

[0006]

To achieve the above object, the means described in claim 1 can be employed. According to this means, the screen control management means obtains a ratio change altitude by multiplying the current viewpoint altitude by a predetermined change ratio every time the altitude change command is input, and obtains the current viewpoint altitude. On the other hand, an altitude that is increased or decreased by the ratio change altitude is set as a new viewpoint altitude. Therefore, it is possible to set a large number of viewpoint altitudes in response to the input of the altitude change command, and as the viewpoint altitude increases, the amount of change in the viewpoint altitude increases,
The user can set a desired viewpoint height with good operability.

Further, since the amount of change in the viewpoint altitude is a predetermined ratio with respect to the current viewpoint altitude, the user can feel the rising or falling of the viewpoint in the three-dimensional map display by inputting the altitude change command. can get. Further, the screen display can be smoothly changed by continuously inputting the altitude change command.

According to the second aspect of the present invention, the screen control management means changes the currently set viewpoint altitude to a constant constant change altitude for the ratio change altitude every time an altitude change command is input. Since only the added altitude is changed, the change amount due to the ratio change altitude becomes dominant at a high viewpoint altitude, and the change amount due to the fixed value change altitude becomes dominant at a low viewpoint altitude. In other words, even in the case of a low viewpoint altitude where the amount of change of the viewpoint altitude in response to the altitude change command tends to be small only with the change amount of the ratio change altitude, the viewpoint altitude changes at least only by the constant value change altitude. Therefore, at the time of setting a low viewpoint altitude, operability is further improved and a smooth screen change can be obtained by continuing to input the altitude change command.

According to the third aspect of the present invention, the screen control management means, when the currently set viewpoint altitude is equal to or lower than the predetermined altitude, changes the fixed value change altitude with respect to the currently set viewpoint altitude. If the altitude exceeds a predetermined altitude, the altitude is changed by the ratio change altitude with respect to the currently set viewpoint altitude. Therefore, substantially the same operation as the means described in claim 2 can be obtained, and the viewpoint height can be set to a desired height with good operability regardless of the height.

According to the fourth aspect of the present invention, the screen control management means can set the line of sight upward or downward independently of the setting of the viewpoint altitude. It is possible to display a three-dimensional map at a position close to a position directly below the viewpoint, and also to display a building, an elevated road, or the like as viewed from the viewpoint position. Thereby, the user can obtain more information from the three-dimensional map display.

According to the fifth aspect, the screen control management means sets the direction of the line of sight upward or downward in association with the setting of the viewpoint altitude, so that the set target is set regardless of the set viewpoint altitude. It can be captured in the display screen.

According to the means described in claim 6, the screen control management means automatically sets such that the higher the viewpoint height is set, the larger the depression angle indicating the line of sight becomes, and the lower the viewpoint height is set. The angle of depression is automatically set so that the lower the angle, the smaller the angle of depression. For example, if the depression angle indicating the line of sight is constant at 45 °, the higher the viewpoint height is set and the wider the map display, the more difficult it is to display the area immediately below the viewpoint position, and conversely, the lower the viewpoint height is. The more the map is set and the more detailed the map display is, the more difficult it is to display an area farther from the viewpoint position.

Therefore, by automatically setting the depression angle in the line of sight direction in accordance with the setting of the viewpoint altitude as described above, the region immediately below the viewpoint position can be obtained regardless of whether the viewpoint altitude is high or low. The region far from the viewpoint is displayed in a well-balanced manner on the screen, and the display can be performed so that the user can easily grasp the entire region extending from near to far from the viewpoint.

According to the means described in claim 7, the screen control management means sets a relatively small change width in the line-of-sight direction when a change command for lowering the viewpoint height is input, and increases the viewpoint height. When a change command is input, the change width is set relatively large. That is, when the width of change of the line of sight with respect to the change of the line of sight is constant, if the viewpoint height is changed to be lower and the scale of the map is changed to be smaller, the person who views the screen displays the map. It seems that the degree of change gradually increases. Conversely, when the viewpoint height is changed so as to increase and the scale of the map changes, the viewer of the screen feels that the degree of the change becomes gradually smaller. Therefore, by setting the range of change in the line-of-sight direction as described above, the viewer of the screen can feel as if the map display changes smoothly with the change in the line-of-sight height.

According to the means described in claim 8, the screen control management means sets the depression angle θ indicating the line of sight direction as follows: θ = N × (maximum depression angle−minimum depression angle) + minimum depression angle N = log2 (viewpoint height / minimum depression angle) Viewpoint altitude) / log2
Since the setting is made based on (maximum viewpoint height / minimum viewpoint height), by using a logarithmic function, appropriate setting can be performed so that the width of change in the line-of-sight direction differs according to the change in height of the viewpoint height.

According to the ninth aspect of the present invention, the specific point on the map ahead of the line of sight is set as the current position on the map. Even when the display changes moment by moment, the screen is drawn with a line of sight looking down on the current position of the vehicle, so that the occupant of the vehicle can easily grasp the current position of the own vehicle in the map displayed on the screen. be able to.

According to the tenth aspect, the screen control management means displays a cursor for indicating a specific point on the screen, and changes the display position of the cursor according to the viewpoint height. That is, for example, when using a conventional map display device for vehicle navigation, the display position of the cursor in the screen is fixed at the center of the screen or at a position slightly before the center in order to make the traveling direction wider. It is supposed to be. Therefore, if the viewpoint height is extremely low and the angle of depression in the line of sight is close to a so-called driver's view in which the angle of depression is near 0 degrees, the cursor may not be displayed in the conventional method. Therefore, in the present invention, by changing the display position of the cursor according to the viewpoint height, it is possible to improve the display position of the cursor so as to be more appropriate than in the conventional method.

According to the eleventh aspect, the screen control management means sets the coordinates indicating the display center of the screen to (X, Y) and sets the rate of change N to N = log2 (viewpoint height / minimum viewpoint height) / log2
Since the display position of the cursor is set by (X, N, Y) as (maximum viewpoint altitude / minimum viewpoint altitude), based on the change rate set according to the change of the viewpoint altitude as in claim 8, The display position of the cursor on the screen can be set to be appropriate.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment in which the map display device of the present invention is applied to a car navigation device will be described below with reference to FIGS. FIG. 1 shows a schematic functional block diagram of the entire configuration of the car navigation device 1.
In FIG. 1, a position detection unit 2 is a GPS (Global P
ositioning System) It is a part that consists of a receiver, a gyro sensor, a vehicle speed sensor, etc., and calculates the current vehicle position. The position detection unit 2 is configured to be usable while interpolating each of the sensors because the sensors have errors having different properties. In this case, if the current position can be calculated, it is not necessary to provide all of these sensors, and it is sufficient to provide at least one of these sensors.

The map data storage 3 is a device for inputting various data including so-called map matching data, map data, and target data for improving the accuracy of position detection, and includes a DVD player, a hard disk device,
It is composed of a CD player and the like.

The switch information input unit 4 (corresponding to an input means in the present invention) is a switch attached to the left, right, up, or down of a display device, which will be described later. It is composed of a switch, a line-of-sight change switch for changing the line-of-sight direction upward and downward, and the like. When this viewpoint altitude change switch and line of sight change switch are operated sporadically,
A viewpoint altitude change command and a line of sight change command for changing the viewpoint altitude and the line of sight only by one step are output, and while the operation state continues, the viewpoint altitude change command and the line of sight change command are continuously output at a predetermined time interval during the operation state. It is output.

The memory unit 5 is composed of, for example, a ROM or a RAM, and the ROM includes the car navigation device 1.
And a RAM for storing an execution program for operating the
, Temporary data when the program is executed, map data acquired from the map data storage unit, and the like are temporarily stored.

The display unit 6 displays a map, a destination selection screen, and the like, and is composed of, for example, a liquid crystal display device. The screen includes a current position mark of the vehicle input from the position detection unit 2, map data input from the map data storage unit 3, and a mark of a route guide line or a target setting point in a state of being superimposed on the map. And other additional data. The voice output unit 7 outputs voice for guidance and explanation of screen operation.

The control unit 8 is mainly composed of a microcomputer, and automatically selects an optimal route from the current position to the destination in accordance with an operation on the switch information input unit 4 to provide a route guide line. It performs a route guidance function to be displayed, performs map matching processing, synthesizes guidance voice, and draws a map according to the set viewpoint altitude and line-of-sight direction.

The control unit 8 includes a map data acquisition unit 9, a map matching unit 10, a route calculation unit 11, and a route guidance unit 1.
2, a drawing unit 13, a screen control management unit 14, and the like.

The map matching section 10 includes a position detecting section 2
The current position of the vehicle is specified on which road using the position information of the vehicle detected in the above and the road shape data of the map data acquired from the map data storage unit 3. At this time, the map data acquisition unit 9 acquires necessary map data from the map data storage unit 3. Further, the user operates the switch information input unit 4 to display a desired map or the like, and sets a destination. The route calculation unit 11 calculates the information on the current position calculated by the map matching unit 10 and the optimum route to the departure point and the destination specified by the user.

The route guide section 12 calculates the result of the route calculation and the road shape data stored in the map data,
The points required for route guidance are calculated from the position information of the intersection and the position information of the railroad crossing, and what kind of route guidance (turn right or turn left) is calculated.

The drawing unit 13 draws a map of the current position, a schematic diagram of a highway, an enlarged view near an intersection near an intersection, etc. in accordance with an instruction from the screen control management unit 14, and a display unit 6.
To be displayed. The screen control management unit 14 (corresponding to a screen control management unit in the present invention) sets the viewpoint height based on a viewpoint height change command input from a viewpoint height change switch. The screen control management unit 14
Sets the gaze direction independently of the viewpoint altitude based on the gaze change command input from the gaze change switch.

The map data obtaining unit 9 obtains the map data required by each processing unit from the map data storage unit 3,
Provided to each processing unit. Each of the above-described processes is executed by using the ROM and the RAM of the memory unit 5.

The map drawn by the drawing unit 13 is a three-dimensional map (for example, a bird's-eye view or a three-dimensional map), and includes building shape data, building height information, road shape data, and the like stored in the map data. Buildings, three-dimensional intersections, and the like are three-dimensionally drawn based on the set viewpoint height and line-of-sight direction.
Further, based on the information calculated by the route guidance unit 12, when the vehicle travels and reaches a position to be route-guided, a desired image is drawn on the drawing unit 13 or a predetermined sound is output to the sound output unit 7. Guide the user to the destination.

Next, the operation of the above configuration will be described with reference to FIGS. By operating the viewpoint height change switch, the user can change the viewpoint height when the map is displayed three-dimensionally on the display unit 6. FIG. 2 shows a flowchart of a viewpoint height setting process performed by the screen control management unit 14. In FIG. 2, the screen control management unit 14 first determines whether or not the viewpoint altitude change switch has been operated (step S1). If the switch has not been operated (NO), the viewpoint altitude setting process ends.
On the other hand, the screen control management unit 14 operates when the viewpoint height change switch is operated and a viewpoint height change command is given (YE
In S), the viewpoint height is set as follows.

That is, based on the viewpoint height set before the change (before the operation of the viewpoint height change switch), the screen control management unit 14 changes the viewpoint height which is increased or decreased by a single operation of the viewpoint height change switch. Amount (altitude change amount)
Is calculated as in the following equation (1) (step S1).
2). Altitude change amount = viewpoint altitude before change × change ratio + minimum change altitude (1) ● In equation (1), the term (viewpoint altitude before change × change ratio) corresponds to the ratio change altitude in the present invention. The change altitude corresponds to the constant value change altitude in the present invention. Then, the screen control management unit 14 determines whether the viewpoint altitude change switch has been operated to the “altitude ascending side” or the “altitude ascending side” (step S3). If (YES), the viewpoint altitude is set according to equation (2) (step S4), and if it is operated on the "altitude lowering side" (NO), the viewpoint altitude is set according to equation (3) (step S5). Viewpoint altitude = viewpoint altitude before change + altitude change amount (2) viewpoint altitude = viewpoint altitude before change−altitude change amount (3) The screen control management unit 14 performs the above-described (1) on the drawing unit 13.
The viewpoint height obtained by the formulas (3) is output, and the display unit 6 is instructed to draw a three-dimensional map viewed from the viewpoint height (step S6), and the setting process of the viewpoint height is completed.

FIG. 3 shows the relationship between the number of operations and the set viewpoint altitude and the relationship between the number of operations and the altitude change amount when the viewpoint altitude change switch is operated on the “elevation ascending side”, by a solid line and a solid line, respectively. Shown by dashed lines. here,
The change ratio is set to 1/16, the minimum change altitude is set to 0.5 m, and the initial viewpoint altitude is set to 0 m.

As shown in FIG. 3, the viewpoint altitude with respect to the number of operations of the viewpoint altitude change switch increases exponentially as a whole, and the initial viewpoint altitude, which was 0 m, becomes almost 600 m by 71 altitude ascent operations. It becomes the viewpoint altitude. Then, as the viewpoint altitude is higher, the ratio change altitude (viewpoint altitude before change × change ratio) in equation (1) becomes larger, and the altitude change amount by operating the viewpoint altitude change switch becomes larger. When the viewpoint altitude is low, the ratio change altitude is small, but the minimum change altitude (constant value change altitude) is added in the equation (1). Altitude rises. If you keep operating the viewpoint altitude change switch,
During the continuation of the operation, the viewpoint height increases by one step at predetermined time intervals according to the curve shown in FIG.

As described above, according to this embodiment,
Each time the viewpoint height change switch is operated, the screen control management unit 14 adds the ratio change height obtained by multiplying the current viewpoint height by the change ratio and the minimum change height, that is, the fixed value change height, to calculate the height change amount. Since a new viewpoint height is set by calculating and adding / subtracting the height change amount to the current viewpoint height, the user can set a large number of viewpoint heights (72 levels in this embodiment).

In this case, since the height change amount increases as the viewpoint height increases, the user can set the viewpoint with good operability even when changing the viewpoint from a low height to a high height. Also, at relatively high viewpoint altitudes,
Since the altitude change amount is substantially constant with respect to the current viewpoint altitude, the user can obtain a feeling of ascending or descending the viewpoint in the three-dimensional map display by operating the viewpoint altitude change switch. And the user keeps the viewpoint altitude change switch in the operating state,
The three-dimensional map display can be smoothly changed with almost continuous movement.

On the other hand, at a relatively low viewpoint altitude, since the altitude change amount is dominated by the constant value change altitude rather than the ratio change altitude, the user operates the viewpoint altitude change switch to reduce the viewpoint altitude to at least the minimum. Only the changing altitude can be changed, and a feeling of rising or falling of the viewpoint of the three-dimensional map display can be obtained. Also, as in the case of a high viewpoint, the three-dimensional map display can be smoothly changed.

Further, the user can set the line of sight upward or downward independently of the setting of the viewpoint altitude by operating the viewpoint change switch. Therefore, for example, the viewpoint altitude is set high and the line of sight is set in the horizontal plane. By setting the distance slightly lower, the entire street can be displayed, or the far side can be displayed beyond the tall building displayed three-dimensionally. In addition, by setting the line of sight upward, the user can, for example, display a building or an elevated road from the current viewpoint position while looking up. By setting the line of sight, the user can obtain more information from the three-dimensional map display.

(Second Embodiment) FIGS. 4 to 6 show a second embodiment of the present invention. The same parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. Only the different parts will be described below. FIG. 4 is a flowchart of the viewpoint altitude setting processing by the screen control management unit 14. Processing steps S7 and S8 are inserted between steps S4 and S5 and step S6.

In step S7, the screen control management unit 1
4 is the viewpoint altitude set in step S4 or S5,
That is, the depression angle in the line-of-sight direction is changed according to the display scale of the map. First, the rate of change N (0 <N <1) of the depression angle θ is set based on equation (4). N = log2 (viewpoint height / minimum viewpoint height) / log2 (maximum viewpoint height / minimum viewpoint height) (4) Here, the minimum viewpoint height and the maximum viewpoint height are, for example, the first viewpoint height.
Are set to 0 m, 600 m, and the like, as in the embodiment.
Further, the logarithmic function is used, as in the first embodiment, by setting the viewpoint altitude to increase and the rate of change of the depression angle θ to increase as the map is displayed in a wide area, and the viewpoint altitude to decrease. This is for setting so that the rate of change of the depression angle θ becomes smaller as the map is displayed in detail. Equation (4) determines the curve of the change locus C of the viewpoint position shown in FIG.

When the rate of change N is determined, the depression angle θ is determined by equation (5). θ = N × (maximum depression angle−minimum depression angle) + minimum depression angle (5) Here, the maximum depression angle is, for example, 90 °, and the minimum depression angle is, for example, 1
It is set to 5 ° or the like. As shown in FIG. 5, the line-of-sight distance L from the viewpoint to the current position (specific point) indicated by the cursor on the map in the three-dimensional map display is L = H · cosec θ, where H is the viewpoint altitude.
... (6), and when the map is displayed two-dimensionally on the same scale, since θ = 90 °, L = H
Becomes

The mark indicating the current position shown in FIG.
The display when viewed from the viewpoint in the figure differs depending on the positional relationship between the current position and the viewpoint in FIG.

In the following step S8, the screen control management section 14 sets the cursor display position Pc for displaying the current position on the map using the rate of change N of the depression angle θ as follows. Pc = (Y coordinate of screen center position) × N When the display position Pc of the cursor is set as described above, it is possible to appropriately display the current position on the map even when the depression angle changes according to the viewpoint altitude. Become.

FIGS. 6A to 6D show examples of changes in the screen display on the display unit 6 drawn in step S6a based on the depression angle θ determined as described above. It is a screen display corresponding to positions A to D. As is clear from FIGS. 6A to 6D, since the depression angle θ decreases as the display scale of the map decreases, the map can be displayed widely over a long distance in the traveling direction.

Also, the display position of the cursor indicating the current position of the automobile gradually moves to the lower side of the screen according to the change of the viewpoint position. In FIG. 6D, the cursor is not displayed on the screen of the display unit 6 because the driver's view is such that the current position substantially matches the viewpoint position as shown in the viewpoint position D. In this case, even if the cursor is not displayed on the screen, the position of the own vehicle can be sufficiently grasped from the shape of the surrounding buildings and the shape of the road in the traveling direction.

FIGS. 7 and 8 show screen display examples based on the prior art for comparison. For example, FIG. 7 shows a method in which the angle of depression in the line of sight in the three-dimensional display is constant, and the viewpoint position approaches the current position at the line of sight as the viewpoint height decreases (scale decreases). In this case, at the viewpoint A shown in FIG.
Although there is no problem similarly to the above, when the viewpoint altitude decreases from the viewpoint B to the viewpoint D, the display area in the traveling direction gradually narrows, and surrounding buildings and the like are not displayed. In FIG. 7D, the traveling direction and surrounding buildings are hardly displayed, and only the display of the road is enlarged. Therefore, it is difficult for the driver to grasp the current position of the vehicle. I will.

In FIG. 8, the depression angle in the line of sight in the three-dimensional display is constant as in FIG. 7, but the viewpoint position is always vertically above the current position, and the viewpoint position decreases as the viewpoint height decreases. It is a system that descends vertically. In this case, at the viewpoint A shown in FIG. 8A, since the display area is far away from the position of the host vehicle, it is difficult to grasp the relationship with the current host vehicle position. From that state, viewpoint B ~
Even when the viewpoint height is lowered toward the viewpoint D, the positional relationship between the displayed map and the current vehicle gradually approaches, but it is difficult to grasp, and in FIG. 8D, FIG.
Similarly to the above, the traveling direction and surrounding buildings are hardly displayed, and only the display of the road is enlarged. On the other hand, in FIG. 6, in both the case where the viewpoint altitude is high and the case where the viewpoint altitude is low, the area near the current position of the own vehicle and the area distant from the current position in the traveling direction are displayed in a well-balanced manner. ing.

As described above, according to the second embodiment, the screen control management unit 14 sets the rate of change N of the depression angle θ in accordance with the setting of the line-of-sight altitude by Expression (4), and sets the depression angle θ to (5 ), The depression angle θ is set small when the viewpoint altitude is set low, and the change width thereof is set relatively small. When the viewpoint altitude is set high, the depression angle θ is set large and the depression angle θ is set large. The range of change is set to be relatively large.

Therefore, both in the case where the viewpoint altitude is high and the case where the viewpoint altitude is low, the area near the current position of the host vehicle and the area far from the current position are displayed on the screen of the display unit 6 in a well-balanced manner. Thus, the display can be performed so that the user can easily grasp the whole of the distance from the viewpoint to the perspective, and the map display can be made to feel as if the map display changes smoothly with the change of the line-of-sight height.

Further, since the specific point on the map ahead of the line of sight is set as the current position of the own vehicle, even when the map display on the screen changes every moment as in the case of using for car navigation, the screen is displayed on the screen. Since the current position of the vehicle is drawn with a line of sight looking down, the user can easily grasp the current position of the vehicle in the map displayed on the screen.

Further, the screen control management unit 14 sets the display position of the cursor on the screen to (X, N · Y) with respect to the display center coordinate (X, Y) of the screen based on the rate of change N of the depression angle θ. ).

In other words, the ratio of the display position of the conventional cursor is fixed, for example, the cursor is displayed at a position 3: 1 from above in the Y coordinate of the screen. Therefore, for example, when the depression angle is extremely small as shown in FIG.
On the near side of the screen, the road at the position where the vehicle has already passed and the surrounding buildings are displayed. On the other hand, according to the second embodiment, the display of the current position on the screen can be appropriately set even at a viewpoint close to the driver's view.

The present invention is not limited to the above embodiment, but can be modified or expanded as follows. When the currently set viewpoint altitude is equal to or less than the predetermined altitude, the screen control management unit 14 sets the amount of altitude change every time the viewpoint altitude change switch is operated to only the constant value change altitude (minimum change altitude), If the set viewpoint altitude exceeds the predetermined altitude, a ratio change altitude obtained by multiplying the current viewpoint altitude by a change ratio may be configured as the altitude change amount. In this case, the same effect as in the above-described embodiment can be obtained.

The screen control management section 14 may set the line of sight upward or downward in association with the setting of the viewpoint height. As a result, a specific target or target area can be automatically captured in the display screen regardless of the set viewpoint altitude. The specific point ahead of the viewing direction on the map indicated by the cursor is not limited to the current position of the vehicle, but may be set in front of the current position. The change rate N such as the depression angle θ is not limited to the expression (4). For example, by determining the rate of change N as N = (viewpoint height) / (maximum viewpoint height), the depression angle may linearly change with respect to the change in viewpoint height. The present invention is not limited to the vehicle navigation device, but can be applied to any device that displays a map three-dimensionally.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing an overall configuration of a first embodiment of the present invention.

FIG. 2 is a flowchart showing viewpoint altitude setting processing;

FIG. 3 is a diagram showing the relationship between the number of operations of a viewpoint height change switch, the viewpoint height, and the amount of change in height.

FIG. 4 is a view corresponding to FIG. 2, showing a second embodiment of the present invention;

FIG. 5 is a diagram showing a change in a viewpoint position in a three-dimensional display from the side.

FIG. 6 is a diagram illustrating an example of a screen display of a display unit, which is drawn according to each viewpoint position.

FIG. 7 is a diagram corresponding to FIG. 6 corresponding to a change in a conventional viewpoint position (part 1);

FIG. 8 is a diagram corresponding to FIG. 6 according to a change in a conventional viewpoint position (part 2);

FIG. 9 is an explanatory diagram of a conventional viewpoint height setting.

[Explanation of symbols]

1 is a car navigation device (map display device), 4 is a switch information input unit (input means), and 14 is a screen control management unit (screen control management means).

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[Procedure amendment]

[Submission date] October 18, 1999 (1999.10.
18)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0032

[Correction method] Change

[Correction contents]

That is, based on the viewpoint height set before the change (before the operation of the viewpoint height change switch), the screen control management unit 14 changes the viewpoint height which is increased or decreased by a single operation of the viewpoint height change switch. Amount (altitude change amount)
Is calculated as in the following equation (1) (step S1).
2). Altitude change amount = viewpoint altitude before change × change ratio + minimum change altitude (1) In this equation (1), (viewpoint altitude before change × change ratio)
Corresponds to the ratio change height in the present invention, and the minimum change height corresponds to the constant value change height in the present invention. Then, the screen control management unit 14 determines whether the viewpoint altitude change switch has been operated on the “altitude ascending side” or the “altitude ascending side” (step S3), and when the switch has been operated on the “altitude ascending side” (step S3). If (YES), the viewpoint altitude is set according to equation (2) (step S4), and if it is operated on the "altitude lowering side" (NO), the viewpoint altitude is set according to equation (3) (step S5). Viewpoint altitude = viewpoint altitude before change + altitude change amount (2) Viewpoint altitude = viewpoint altitude before change−altitude change amount (3) The surface control management unit 14 applies the above formulas (1) to (1) to the drawing unit 13. The viewpoint height obtained by the expression 3) is output, and the display unit 6 is instructed to draw a three-dimensional map viewed from the viewpoint height (step S6), and the viewpoint height setting process ends.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction contents]

When the rate of change N is determined, the depression angle θ is determined by equation (5). θ = N × (maximum depression angle−minimum depression angle) + minimum depression angle (5) Here, the maximum depression angle is, for example, 90 °, and the minimum depression angle is, for example, 1
It is set to 5 ° or the like. As shown in FIG. 5, the line-of-sight distance L from the viewpoint to the current position (specific point) indicated by the cursor 15 on the map in the three-dimensional map display is given by: L = H · cosec θ … (6) When the map is displayed two-dimensionally at the same scale, θ =
Since it is 90 °, L = H.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0043

[Correction method] Change

[Correction contents]

In the following step S8, the screen control manager 14 sets the display position Pc of the cursor 15 for displaying the current position on the map using the rate of change N of the depression angle θ as follows. Pc = (Y coordinate of the screen center position) × N By setting the display position Pc of the cursor 15 in this way, even if the depression angle changes according to the viewpoint altitude, the current position on the map can be appropriately displayed. Becomes

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0045

[Correction method] Change

[Correction contents]

A cursor 1 indicating the current position of the car
The display position of No. 5 also gradually moves to the lower side of the screen according to the change of the viewpoint position. And in FIG. 6D,
As shown in the viewpoint position D, the cursor 15 is not displayed on the screen of the display unit 6 because the driver's view is such that the current position and the viewpoint position substantially match. In this case, even if the cursor 15 is not displayed on the screen, the position of the own vehicle can be sufficiently grasped from the shape of the surrounding buildings and the road shape in the traveling direction.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0046

[Correction method] Change

[Correction contents]

FIGS. 7 and 8 show screen display examples based on the prior art for comparison. For example, FIG. 7 is a constant depression angle of the line of sight direction in the three-dimensional display, as the viewpoint altitude is lower (scales rather small), the viewpoint position is a method in which approaches the current position in the sight-line end. In this case, at the viewpoint A shown in FIG.
Although there is no problem similarly to the above, when the viewpoint altitude decreases from the viewpoint B to the viewpoint D, the display area in the traveling direction gradually narrows, and surrounding buildings and the like are not displayed. In FIG. 7D, the traveling direction and surrounding buildings are hardly displayed, and only the display of the road is enlarged. Therefore, it is difficult for the driver to grasp the current position of the vehicle. I will.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0049

[Correction method] Change

[Correction contents]

Therefore, both in the case where the viewpoint altitude is high and the case where the viewpoint altitude is low, the area near the current position of the host vehicle and the area far from the current position are displayed on the screen of the display unit 6 in a well-balanced manner. The display can be performed so that the user can easily grasp the entire area from the viewpoint position to the distance from the viewpoint position. At the same time, it is felt that the map display changes smoothly with a change in the line-of-sight altitude. Can be done.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0051

[Correction method] Change

[Correction contents]

Further, the screen control management unit 14 changes the display position of the cursor 15 in the screen with respect to the display center coordinates (X, Y) of the screen based on the change rate N of the depression angle θ by (X, N ·
Y).

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0054

[Correction method] Change

[Correction contents]

The specific point ahead of the line of sight on the map indicated by the cursor 15 is not limited to the current position of the vehicle, but may be set ahead of the current position. The change rate N such as the depression angle θ is not limited to the expression (4). For example, by determining the rate of change N as N = (viewpoint height) / (maximum viewpoint height), the depression angle may linearly change with respect to the change in viewpoint height. The present invention is not limited to the vehicle navigation device, but can be applied to any device that displays a map three-dimensionally.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] Explanation of sign

[Correction method] Change

[Correction contents]

[Description of Signs] 1 is a car navigation device (map display device), 4 is a switch information input unit (input means), 14 is a screen control management unit (screen control management means) , and 15 is a cursor .

[Procedure amendment 10]

[Document name to be amended] Drawing

[Correction target item name] Fig. 5

[Correction method] Change

[Correction contents]

FIG. 5

[Procedure amendment 11]

[Document name to be amended] Drawing

[Correction target item name] Fig. 6

[Correction method] Change

[Correction contents]

FIG. 6

[Procedure amendment 12]

[Document name to be amended] Drawing

[Correction target item name] Fig. 7

[Correction method] Change

[Correction contents]

FIG. 7

[Procedure amendment 13]

[Document name to be amended] Drawing

[Correction target item name] Fig. 8

[Correction method] Change

[Correction contents]

FIG. 8

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masatoshi Yabo 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside Denso Corporation (72) Inventor Takashi Ichida 1-1-1, Showa-cho, Kariya-shi, Aichi Co., Ltd. F term in DENSO (reference) 2C032 HB22 HC08 HC23 2F029 AA02 AB01 AB07 AB09 AC01 AC02 AC04 AC18 AD01 5H180 AA01 BB13 FF04 FF05 FF07 FF22 FF25 FF27 FF33 FF38

Claims (11)

[Claims] 1. A map display device for three-dimensionally displaying a map on a screen, comprising: input means for inputting an altitude change command for raising or lowering a viewpoint height when the map is three-dimensionally displayed; Every time an altitude change command is input, an altitude that is increased or decreased by a ratio change altitude obtained by multiplying the currently set viewpoint altitude by a predetermined change ratio is set as a new viewpoint altitude. A map display device, comprising: 2. The screen control management unit according to claim 1, wherein each time an altitude change command is input to said input unit, an altitude obtained by adding a constant constant altitude to said ratio altitude with respect to a currently set viewpoint altitude. 2. The map display device according to claim 1, wherein the altitude increased or decreased by only the altitude is set as a new viewpoint altitude. 3. The screen control management means, if the currently set viewpoint height is equal to or lower than a predetermined height, every time a height change command is input to the input means, the currently set viewpoint height is set. 2. The map display device according to claim 1, wherein an altitude which is increased or decreased by a fixed constant change altitude is set as a new viewpoint altitude. 4. The apparatus according to claim 1, wherein the screen control management means can set the line of sight upward or downward independently of the setting of the viewpoint altitude. Map display device. 5. The map display device according to claim 1, wherein the screen control management means can set a line of sight upward or downward in association with the setting of the viewpoint altitude. . 6. The screen control management means automatically sets such that the higher the viewpoint height is set, the larger the depression angle indicating the line-of-sight direction becomes, and the lower the viewpoint height is, the smaller the depression angle becomes. 6. The map display device according to claim 5, wherein the setting is automatically made to be as follows. 7. When a change command for lowering the viewpoint height is input, the screen control management means sets a relatively small change width in the line-of-sight direction and receives a change command for raising the viewpoint height. 7. In this case, the change width in the line-of-sight direction is set relatively large.
A map display device as described. 8. The screen control management means calculates a depression angle θ indicating the line-of-sight direction as follows: θ = N × (maximum depression angle−minimum depression angle) + minimum depression angle N = log2 (viewpoint height / minimum viewpoint height) / log2
The map display device according to claim 7, wherein the setting is performed based on (maximum viewpoint height / minimum viewpoint height). 9. The method according to claim 5, wherein the specific point on the map ahead of the line of sight is a current position on the map.
9. The map display device according to any one of claims 8 to 8. 10. The screen control management means displays a cursor for indicating the specific point on the screen, and changes a display position of the cursor according to a viewpoint height. 10. The map display device according to any one of 5 to 9. 11. The screen control management means sets coordinates indicating the display center of the screen to (X, Y), and sets a change rate N to N = log2 (viewpoint height / minimum viewpoint height) / log2.
The map display device according to claim 10, wherein the display position of the cursor is set by (X, N, Y), where (maximum viewpoint altitude / minimum viewpoint altitude).