JP2017161238A - Map screen displaying device, and map screen displaying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a map screen displaying device and a map screen displaying method that can prevent, when map screens are displayed in a heading-up mode, the topography of the area around the vehicle equipped with the device from being incorrectly recognized.SOLUTION: A map screen displaying device, as it is equipped with a traveling direction detecting unit 101 that detects the traveling direction of a vehicle on which the device is mounted and a map screen displaying unit 103 that displays, when map screens are displayed in a heading-up mode, the map screens including a background image to which shades are added in different modes according to the traveling direction of the vehicle detected by the traveling direction detecting unit 101, enables the topography to be correctly recognized even if the bearing that represents the upper side of the vehicle changes in the map screen along with variations of its traveling direction of the vehicle, by varying the mode of the shade in the background image according to the changed traveling direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a map screen display device and a map screen display method, and in particular, a map screen display that allows a three-dimensional view of a terrain by adding a shadow to a slope portion of a mountain in a background image constituting the map screen. It is suitable for use in an apparatus and a map screen display method.

  Conventionally, on a map screen displayed by a map screen display device (for example, a navigation device), a technique for three-dimensionally displaying surrounding buildings and terrain has been used. For example, the following Patent Document 1 discloses a technique for displaying mountain ranges by drawing each section of mesh-like map data with color information corresponding to the height in a bird's-eye view from the vehicle position to a distant place. Has been.

  Conventionally, in a mountain-shaped background image constituting a map screen when viewed from directly above the sky, it is assumed that light is irradiated from a predetermined direction, and an image in which a shadow is added to a shadowed portion at that time A technique is used in which the surrounding terrain can be viewed three-dimensionally by displaying.

JP 2006-039014 A

  FIG. 11 is a diagram illustrating a display example of a conventional map screen. A map screen 1100 shown in FIGS. 11A and 11B is a map screen when the vicinity of the vehicle position of the vehicle is viewed from directly above the vehicle. It is generated by superimposing a surrounding map image and a background image 1120 representing the topography. FIG. 11A shows a state where the traveling direction of the vehicle is north when the map screen 1100 is displayed in the heading-up mode. That is, the upper side of the map screen 1100 is north. FIG. 11B shows a state when the traveling direction of the vehicle is south when the map screen 1100 is displayed in the heading-up mode. That is, the upper side of the map screen 1100 is south.

  In this map screen 1100, the background image 1120 is assumed to be irradiated with light from the northwest direction when the north is the upper side, as in a general map screen. Has been created. That is, the background image 1120 is shaded so that the topography can be correctly recognized when the north of the map screen 1100 is on the upper side.

  For example, in the background image 1120, a valley bottom 1121, a ridge line 1122, and a ridge line 1123 are shown. A west slope 1131 is shown between the valley bottom 1121 and the ridgeline 1122. An east side slope 1132 is shown between the valley bottom 1121 and the ridge line 1123. And the shadow is added to the part which becomes a shadow when light is irradiated from the northwest direction. As a result, most of the west slope 1131 is shaded. In FIG. 11, each shade is shown with the same density on the map screen 1100, but each shade actually has a shading.

  As shown in FIG. 11 (a), the map screen 1100 with the shadow on most of the west slope 1131 correctly displays the topography of the valley bottom 1121, the ridgeline 1122, and the ridgeline 1123 as shown in FIG. It can be visually recognized. That is, it is possible to intuitively understand that the vehicle is traveling on the road along the valley bottom 1121.

  However, in the map screen 1100, when the south is on the upper side as shown in FIG. 11B, the topography of the valley bottom 1121 is mistakenly recognized as a ridgeline. Moreover, the topography of the ridgelines 1122 and 1123 is mistakenly recognized as a valley bottom. That is, there is a problem that the vehicle is mistakenly recognized as traveling on the road along the ridgeline although the vehicle is actually traveling on the road along the valley bottom 1121.

  The present invention has been made to solve such a problem, so that when the map screen is displayed in the heading-up mode, the terrain around the vehicle position is not mistakenly recognized. The purpose is to be able to.

  In order to solve the above-described problems, in the present invention, the map screen is displayed in a heading-up mode in a configuration configured to display a map screen including a background image that can be viewed stereoscopically by adding a shadow. Is displayed, a map screen including a background image that is shaded in a different manner is displayed according to the detected traveling direction of the vehicle.

  According to the present invention configured as described above, when the map screen is displayed in the heading-up mode, the direction on the upper side of the map screen changes as the traveling direction of the vehicle changes. In addition, since the mode of shading in the background image changes according to the changed traveling direction, the topography (for example, a ridgeline, a valley bottom, a slope, etc.) can be correctly recognized. Therefore, according to the present invention, when the map screen is displayed in the heading-up mode, it is possible to prevent the terrain around the vehicle position from being mistakenly viewed.

It is a block diagram which shows the function structural example of the map screen display apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows an example of the determination conditions memorize | stored in the determination condition memory | storage part which concerns on 1st Embodiment of this invention. It is a flowchart which shows an example of the process by the map screen display apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the example of a display of the map screen by the map screen display apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the function structural example of the map screen display apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart which shows an example of the process by the map screen display apparatus which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the function structural example of the map screen display apparatus which concerns on 3rd Embodiment of this invention. It is a figure which shows the example of a change of the determination conditions by the boundary change part which concerns on 3rd Embodiment of this invention. It is a block diagram which shows the function structural example of the map screen display apparatus which concerns on 4th Embodiment of this invention. It is a flowchart which shows an example of the process by the map screen display apparatus which concerns on 4th Embodiment of this invention. It is a figure which shows the example of a display of the conventional map screen.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a functional configuration example of a map screen display device 100 according to the first embodiment of the present invention.

  As shown in FIG. 1, a map data storage unit 11, a vehicle position detection device 12, and a display 13 are connected to the map screen display device 100 of the first embodiment. Moreover, the map screen display apparatus 100 is provided with the advancing direction detection part 101, the map screen production | generation part 102, the map screen display part 103, and the shading change part 104 as the function structure. Further, the map screen display device 100 includes a determination condition storage unit 100A.

  Each of the functional blocks 101 to 104 can be configured by any of hardware, DSP (Digital Signal Processor), and software. For example, when configured by software, each of the functional blocks 101 to 104 is actually configured by including a CPU, RAM, ROM, etc. of a computer, and a program stored in a recording medium such as RAM, ROM, hard disk, or semiconductor memory. Is realized by operating.

  The map data storage unit 11 stores map data. The map data includes node information, road link information, facility data, place name data, and the like. The map data includes a background image representing the topography. In this background image, it is assumed that light is emitted from the northwest direction located in the upper left when north is set as the upper side, and a shadow is added to a shadow portion at that time.

  The own vehicle position detection device 12 detects the current position of the vehicle (hereinafter referred to as “own vehicle position”). The own vehicle position detection device 12 includes, for example, a GPS (Global Positioning System) and an autonomous navigation unit.

  The display 13 displays various display screens (for example, a map screen). As the display 13, for example, a liquid crystal display, an organic EL display, or the like is used.

  The traveling direction detection unit 101 detects the traveling direction of the vehicle. For example, the traveling direction of the vehicle is detected based on a signal acquired from the autonomous navigation unit of the vehicle position detection device 12.

  The map screen generation unit 102 generates a map screen around the vehicle position detected by the vehicle position detection device 12. Specifically, the map screen generation unit 102 generates a map image around the vehicle position based on the map data stored in the map data storage unit 11. Then, the map screen generation unit 102 superimposes the generated map image and the background image read from the map data storage unit 11, thereby displaying a map screen when the vicinity of the vehicle position of the vehicle is viewed from directly above the sky. Generate.

  The map screen display unit 103 displays the map screen generated by the map screen generation unit 102 on the display 13. The map screen display unit 103 can display the map screen in the north up mode or the heading up mode. When the map screen display unit 103 displays the map screen in the heading-up mode, the map screen display unit 103 rotates the map screen so that the direction in which the vehicle is traveling is always on the upper side. Further, when the map screen display unit 103 displays the map screen in the north up mode, the map screen display unit 103 displays the map screen so that the north is always on the upper side regardless of the traveling direction of the vehicle.

  When the map screen is displayed in the heading-up mode, the shading change unit 104 changes the background image (prior to the change) when the traveling direction of the vehicle detected by the traveling direction detection unit 101 is changed. By changing the density value of each pixel in the background image constituting the map screen generated by the map screen generation unit 102, a map screen in which the background image is shaded in a different manner from that before the change is displayed. So that

  Specifically, as shown in FIG. 2, in the determination condition storage unit 100A, as the determination condition for determining whether or not the density of each pixel in the background image is inverted, the density of each pixel in the background image is displayed. A non-inversion range, which is a range of directions that are not inverted, and an inversion range, which is a range of directions in which the density of each pixel in the background image is inverted, are defined. The non-inversion range is a range of directions including north. Further, the inversion range is a range in the direction outside the non-inversion range including the south. Further, the boundary between the non-inversion range and the inversion range is defined in the northeast and southwest. The shade changing unit 104 regards the northeast as a boundary as being within the non-inversion range. On the other hand, the shade changing unit 104 regards the southwestern boundary as the boundary within the inversion range.

  When the direction of travel of the vehicle changes from the direction in the non-inversion range to the direction in the inversion range beyond the boundary, the shading change unit 104 displays the background image (map screen generation unit) displayed before the change. The map screen in which the shadow of the background image is inverted is generated by inverting the density value of each pixel in the background image read out from the map data storage unit 102 by 102. For example, when the shading of each pixel is expressed by 256 gradations, the shading changing unit 104 sets each pixel in the background image as 0 → 255, 1 → 254,... 254 → 1,255 → 0. Inverts the density value. As a result, when the traveling direction of the vehicle is changed within the inversion range, a map screen in which the density value of each pixel in the background image is inverted is displayed on the display 13 so that the terrain can be visually recognized correctly. .

  Conversely, when the vehicle traveling direction is changed from the direction in the inversion range to the direction in the non-inversion range beyond the boundary, the shading change unit 104 displays the background image (map) displayed before the change. After being read out from the map data storage unit 11 by the screen generation unit 102, the density value of each pixel in the background image (in which the density value of each pixel is inverted) is further inverted, thereby restoring the shade of the background image. . Thereby, when the traveling direction of the vehicle is changed within the original non-inverted range, the map screen including the original background image in which the density value of each pixel is not inverted is displayed on the display 13, Will be visible correctly.

[Example of judgment conditions]
FIG. 2 is a diagram illustrating an example of determination conditions stored in the determination condition storage unit 100A according to the first embodiment of the present invention. The determination condition shown in FIG. 2 is that the northeast and southwest are defined as boundaries, the range on the north side of the boundary is set as the non-inversion range, and the range on the south side of the boundary is set as the inversion range.

  In other words, when the vehicle traveling direction is within the non-inverted range, this determination condition is that the terrain can be correctly visually recognized by displaying a background image in which the density value of each pixel is not inverted, and the vehicle traveling direction is reversed. If it is within the range, it is based on the idea that the terrain can be correctly visually recognized by displaying a background image in which the density value of each pixel is inverted.

  Based on this determination condition, the shading change unit 104 determines whether the traveling direction of the vehicle detected by the traveling direction detection unit 101 is within the non-inversion range or the inversion range.

  Then, when the shade change unit 104 determines that the traveling direction of the vehicle is within the non-inversion range, the density change unit 104 does not invert the density value of each pixel in the background image. As a result, when the traveling direction of the vehicle is within the non-inversion range, a map screen in which the density value of each pixel in the background image is not inverted is displayed on the display 13 and the terrain can be visually recognized correctly. .

  On the other hand, when determining that the traveling direction of the vehicle is within the inversion range, the density changing unit 104 inverts the density value of each pixel in the background image. As a result, when the traveling direction of the vehicle is within the inversion range, a map screen in which the density value of each pixel in the background image is inverted is displayed on the display 13 so that the terrain can be visually recognized correctly.

  Note that the shade changing unit 104 regards the northeast as a boundary as being within the non-inversion range. This is because when the northeast of the map screen is actually turned upward, it is possible to visually recognize the terrain without inverting the density value of each pixel in the background image.

  In addition, the shade changing unit 104 regards the southwestern boundary as being within the inversion range. This is because when the southwest of the map screen is actually turned upward, the topography can be correctly recognized by inverting the density value of each pixel in the background image.

[Example of processing by map screen display device 100]
FIG. 3 is a flowchart showing an example of processing by the map screen display device 100 according to the first embodiment of the present invention. The process shown in FIG. 3 is repeatedly executed, for example, when the map screen display device 100 is turned on and until the map screen display device 100 is turned off.

  First, the map screen generation unit 102 reads map data and background images around the vehicle position from the map data storage unit 11 (step S302). Then, the map screen generation unit 102 determines whether or not to display the map screen in the heading-up mode by referring to the setting information stored in the system memory (step S304).

  Here, when the map screen generating unit 102 determines that the map screen is not displayed in the heading-up mode (step S304: No), the map screen generating unit 102 reads the map around the vehicle position read in step S302. Based on the data and the background image, a map screen for the north up mode is generated (step S306). And the map screen display part 103 displays the map screen produced | generated by step S306 on the display 13 (step S314), and the map screen display apparatus 100 complete | finishes a series of processes shown in FIG.

  On the other hand, when the map screen generation unit 102 determines that the map screen is displayed in the heading-up mode (step S304: Yes), the traveling direction detection unit 101 detects the traveling direction of the vehicle (step S308). Then, the shade changing unit 104 determines whether or not the traveling direction of the vehicle detected in step S308 is within the inversion range (step S310).

  Here, when the shade change unit 104 determines that the traveling direction of the vehicle detected in step S308 is not within the inversion range (step S310: No), the map screen generation unit 102 reads the own vehicle read in step S302. Based on the map data around the position and the background image, a map screen for heading up is generated (step S312). And the map screen display part 103 displays the map screen produced | generated by step S312 on the display 13 (step S314), and the map screen display apparatus 100 complete | finishes a series of processes shown in FIG.

  On the other hand, when the shade changing unit 104 determines that the traveling direction of the vehicle detected in step S308 is within the inversion range (step S310: Yes), the shade changing unit 104 in the background image read in step S302. The density value of each pixel is inverted (step S316). Then, the map screen generation unit 102 performs heading-up based on the map data around the vehicle position read in step S302 and the background image in which the density value of each pixel is inverted in step S316. A map screen is generated (step S318). And the map screen display part 103 displays the map screen produced | generated by step S318 on the display 13 (step S320). And the map screen display apparatus 100 complete | finishes a series of processes shown in FIG.

[Map screen display example]
FIG. 4 is a diagram showing a display example of a map screen by the map screen display device 100 according to the first embodiment of the present invention. A map screen 400 shown in FIGS. 4A and 4B is a map screen when the vicinity of the vehicle position of the vehicle is viewed from directly above the vehicle. It is generated by superimposing a surrounding map image and a background image 420 representing the topography. FIG. 4A shows a state when the traveling direction of the vehicle is north when the map screen 400 is displayed in the heading-up mode. That is, the upper side of the map screen 400 is north. FIG. 4B shows a state when the traveling direction of the vehicle is south when the map screen 400 is displayed in the heading-up mode. That is, the upper side of the map screen 400 is south.

  In this map screen 400, the background image 420 is assumed to be irradiated with light from the northwest direction located at the upper left when north is the upper side, as in a general map screen. It is created by adding shading to the part. That is, the background image 420 is shaded so that the topography can be correctly recognized when the north of the map screen 400 is on the upper side.

  For example, in the background image 420, a valley bottom 421, a ridge line 422, and a ridge line 423 are shown. A west slope 431 is shown between the valley bottom 421 and the ridgeline 422. An east side slope 432 is shown between the valley bottom 421 and the ridge line 423. And the shadow is added to the part which becomes a shadow when light is irradiated from the northwest direction. Thereby, most of the west slope 431 is shaded. In FIG. 4, each shadow is shown with the same density on the map screen 400, but in reality, each shadow has a shading.

  As shown in FIG. 4 (a), the map screen 400 in which most of the west slope 431 is shaded in this manner correctly displays the topography of the valley bottom 421, the ridgeline 422, and the ridgeline 423. It can be visually recognized. That is, it is possible to intuitively understand that the vehicle is traveling on a road along the valley bottom 421.

  On the other hand, as shown in FIG. 4B, the map screen 400 is displayed as if the density value of each pixel in the background image 420 is inverted by the shading change unit 104 when the south is on the upper side. Shadows are added as if light was radiated from the southwest direction located on the upper left. For this reason, the map screen 400 can correctly visually recognize the topography of the valley bottom 421, the ridgeline 422, and the ridgeline 423 even when the south is on the upper side. That is, it is possible to intuitively understand that the vehicle is traveling on the road along the valley bottom 421.

  As described above, according to the first embodiment of the present invention, when the map screen 400 is displayed in the heading-up mode, the direction on the upper side of the map screen 400 is changed as the traveling direction of the vehicle changes. Even if it is changed, the shaded aspect in the background image 420 changes according to the changed traveling direction, so that the topography (the valley bottom 421, the ridge lines 422, 423, the west slope 431, the east slope 432, etc.) can be visually recognized correctly. become able to. Therefore, according to the first embodiment of the present invention, when the map screen 400 is displayed in the heading-up mode, it is possible to prevent the terrain around the vehicle position from being mistakenly viewed.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS. Only the changes from the first embodiment will be described below. FIG. 5 is a block diagram illustrating a functional configuration example of the map screen display device 100a according to the second embodiment of the present invention.

  A map screen display device 100a shown in FIG. 5 is the first embodiment in that it includes an image switching unit 105 instead of the shade changing unit 104, and a map data storage unit 11a instead of the map data storage unit 11. Different from the map screen display device 100 of FIG.

  The map data storage unit 11a stores a background image for a non-inversion range that does not change the shade of each pixel in the background image, and a background image for an inversion range that changes the shade of each pixel in the background image. As in the background image 420 shown in FIG. 4A, the background image for the non-inverted range is assumed to be irradiated with light from the northwest direction located at the upper left when the north is the upper side. A shadow is added to the shadowed part. On the other hand, the background image for the inversion range is obtained by inverting the shade of each pixel of the background image for the non-inversion range, like the background image 420 shown in FIG. That is, it is assumed that light is emitted from the southeast direction located at the upper left when the south is the upper side, and a shadow is added to the shadowed portion at that time.

  When the traveling direction of the vehicle is changed from the direction in the non-inversion range to the direction in the inversion range, the image switching unit 105 reads the background image read from the map data storage unit 11a from the background image for the non-inversion range. Switch to the background image. Then, the image switching unit 105 supplies the read background image for the inversion range to the map screen generation unit 102. In response to this, the map screen generation unit 102 generates a map screen based on the background image for the inversion range supplied from the image switching unit 105 and the map data read from the map data storage unit 11. Thereby, when the traveling direction of the vehicle is changed within the inversion range, a map screen in which the density value of each pixel is inverted is displayed on the display 13 so that the terrain can be visually recognized correctly.

  Conversely, the image switching unit 105 reads the background image read from the map data storage unit 11a from the background image for the inversion range when the traveling direction of the vehicle is changed from the direction in the inversion range to the direction in the non-inversion range. Switch to the background image for the non-inverted range. Then, the image switching unit 105 supplies the read background image for the non-inversion range to the map screen generation unit 102. In response to this, the map screen generation unit 102 generates a map screen based on the background image for the non-inversion range supplied from the image switching unit 105 and the map data read from the map data storage unit 11a. As a result, when the traveling direction of the vehicle is changed within the original non-inverted range, a map screen in which the density value of each pixel is not inverted is displayed on the display 13 so that the terrain can be visually recognized correctly. Become.

[Example of processing by map screen display device 100a]
FIG. 6 is a flowchart showing an example of processing by the map screen display device 100a according to the second embodiment of the present invention. The process shown in FIG. 6 is repeatedly executed, for example, when the map screen display device 100a is turned on and until the map screen display device 100a is turned off.

  First, the map screen generation unit 102 reads map data around the vehicle position from the map data storage unit 11a (step S602). Then, the map screen generation unit 102 determines whether or not to display the map screen in the heading-up mode by referring to the setting information stored in the system memory (step S604).

  Here, when the map screen generation unit 102 determines that the map screen is not displayed in the heading-up mode (step S604: No), the image switching unit 105 reads the background image for the non-inverted range from the map data storage unit 11a. (Step S606). Then, the map screen generation unit 102 uses the map data for the north up mode based on the map data around the vehicle position read in step S602 and the background image for the non-inverted range read in step S606. A map screen is generated (step S608). And the map screen display part 103 displays the map screen produced | generated by step S608 on the display 13 (step S620), and the map screen display apparatus 100a complete | finishes a series of processes shown in FIG.

  On the other hand, when the map screen generation unit 102 determines that the map screen is displayed in the heading-up mode (step S604: Yes), the traveling direction detection unit 101 detects the traveling direction of the vehicle (step S610). Then, the image switching unit 105 determines whether or not the traveling direction of the vehicle detected in step S610 is within the inversion range (step S612).

  Here, when the image switching unit 105 determines that the traveling direction of the vehicle detected in step S610 is within the inversion range (step S612: Yes), the image switching unit 105 uses the background image for the inversion range as map data. Reading from the storage unit 11a (step S614). Then, the map screen generation unit 102 creates a heading-up map screen based on the map data around the vehicle position read in step S602 and the background image for the inversion range read in step S614. Is generated (step S618). And the map screen display part 103 displays the map screen produced | generated by step S618 on the display 13 (step S620), and the map screen display apparatus 100a complete | finishes a series of processes shown in FIG.

  On the other hand, when the image switching unit 105 determines that the traveling direction of the vehicle detected in step S610 is not within the inversion range (step S612: No), the image switching unit 105 stores the background image for the non-inversion range as map data. Reading from the unit 11a (step S616). Then, the map screen generation unit 102 creates a heading-up map based on the map data around the vehicle position read in step S602 and the background image for the non-inverted range read in step S616. A screen is generated (step S618). And the map screen display part 103 displays the map screen produced | generated by step S618 on the display 13 (step S620), and the map screen display apparatus 100a complete | finishes a series of processes shown in FIG.

  As described above, according to the second embodiment of the present invention, when the map screen 400 is displayed in the heading-up mode, the direction on the upper side of the map screen 400 is changed as the traveling direction of the vehicle changes. Even if it is changed, the display of the shadow is changed by switching the reading of the background screen 420 so that the topography (the valley bottom 421, the ridge lines 422, 423, the west slope 431, the east slope 432, etc.) can be correctly visually recognized. become. Therefore, according to the second embodiment of the present invention, when the map screen 400 is displayed in the heading-up mode, the terrain around the vehicle position can be prevented from being mistakenly viewed.

  Note that according to the second embodiment, it is necessary to store twice as many background images in the map data storage unit 11a as compared to the first embodiment. For this reason, when the storage capacity of a memory, a hard disk, or the like is not sufficient, it is preferable to employ a method of inverting the density value of each pixel in the background image as in the first embodiment.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIGS. Only the changes from the first embodiment will be described below. FIG. 7 is a block diagram illustrating a functional configuration example of the map screen display device 100b according to the third embodiment of the present invention.

  The map screen display device 100b shown in FIG. 7 is different from the map screen display device 100 of the first embodiment in that it further includes a boundary changing unit 106. The boundary changing unit 106 changes the boundary between the non-inversion range and the inversion range in the determination conditions stored in the determination condition storage unit 100A.

  Specifically, the boundary changing unit 106 determines whether or not the traveling direction of the vehicle detected by the traveling direction detection unit 101 is in a direction that is a boundary between the non-inversion range and the inversion range. Here, the boundary changing unit 106 determines that the traveling direction of the vehicle is a boundary when the traveling direction of the vehicle detected by the traveling direction detection unit 101 is a direction having a boundary for a predetermined time or longer. You may make it judge that it exists in the direction. In addition, the boundary changing unit 106 determines that the traveling direction of the vehicle is the boundary when the traveling direction of the vehicle detected by the traveling direction detection unit 101 straddles the boundary direction more than a predetermined number of times during a predetermined time. You may make it judge that it exists in the direction.

  When the boundary changing unit 106 determines that the traveling direction of the vehicle is in the direction that is the boundary between the non-inversion range and the inversion range when the background image for the non-inversion range is displayed, the non-inversion range Change the boundary between and the inversion range to the inversion range.

  If the boundary changing unit 106 determines that the traveling direction of the vehicle is in the direction of the boundary between the non-inversion range and the inversion range when the background image for the inversion range is displayed, the non-inversion The boundary between the range and the inversion range is changed to the non-inversion range side.

[Example of changing judgment conditions]
FIG. 8 is a diagram illustrating an example of changing the determination condition by the boundary changing unit 106 according to the third embodiment of the present invention. In the initial state, the determination condition shown in FIG. 8 is the same as the determination condition of the first embodiment (see FIG. 2), with the northeast and southwest as boundaries, the north side of the boundary as a non-inversion range, The range on the south side is defined as the reversal range.

  FIG. 8A shows an example in which the boundary located in the northeast is changed to the inversion range side. For example, when the boundary changing unit 106 determines that the traveling direction of the vehicle is in the northeast of the boundary, the background image for the non-inversion range (that is, the background image in which each pixel is not inverted) has been displayed. In this case, as shown in FIG. 8A, the boundary changing unit 106 changes the boundary that is in the northeast to the non-inversion range side (in the example of FIG. 8A, east to northeast).

  FIG. 8B shows an example in which the southwest boundary is changed to the non-inversion range side. For example, when the boundary changing unit 106 determines that the traveling direction of the vehicle is in the southwest of the boundary, the background image for the inversion range (that is, the background image in which each pixel is inverted) has been displayed. As shown in FIG. 8B, the boundary changing unit 106 changes the boundary located in the southwest to the non-inversion range side (west-southwest in the example of FIG. 8B).

  Thus, according to the third embodiment of the present invention, when the traveling direction of the vehicle is in the direction with the boundary, the traveling direction of the vehicle crosses the original boundary and is reversed by changing the boundary. Even when switching between the side and the non-inversion range side many times, it is possible to prevent frequent reversal of the density of each pixel in the background image. Thereby, flickering of the screen can be prevented.

  In the third embodiment, the boundary between the inversion range and the non-inversion range is changed based on the configuration of the first embodiment (the configuration in which the density value of each pixel in the background image is inverted). The boundary between the inversion range and the non-inversion range may be changed based on the configuration of the second embodiment (configuration of switching the background image to be read).

  In the third embodiment, the changed boundary may be restored when a predetermined condition is satisfied. For example, as shown in FIG. 8A, when the northeast boundary is changed to east northeast, when the vehicle traveling direction detected by the traveling direction detection unit 101 becomes east northeast, the boundary is You may make it return to.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG. 9 and FIG. Only the changes from the second embodiment will be described below. FIG. 9 is a block diagram illustrating a functional configuration example of the map screen display device 100c according to the fourth embodiment of the present invention.

  A map screen display device 100c shown in FIG. 9 includes an image switching unit 105 ′ instead of the image switching unit 105, a point including a map data storage unit 11b instead of the map data storage unit 11a, and a determination condition storage unit. It differs from the map screen display device 100a of the second embodiment in that it does not include 100A.

  The map data storage unit 11b stores a background image in which a shade is added to a different part for each of the three or more directions. For example, in the case of four directions, the map data storage unit 11b stores a background image in which shadows are added to different portions for each of north, east, south, and west. For example, in the case of eight directions, the map data storage unit 11b stores background images in which shadows are added to different portions for each of north, northeast, east, southeast, south, southwest, west, and northwest. The plurality of directions for generating the background image are not limited to the four directions and the eight directions. For example, the direction may be 16 directions or more.

  The background image of each direction is obtained by irradiating light from the direction located at the upper left when the direction is on the upper side, and a shadow is added to the shadow portion at that time. That is, a shadow is added so that the terrain can be correctly recognized when the direction is on the upper side.

  For example, assuming that the background image for east was illuminated from the northeast, which is the direction located in the upper left, when the east was on the upper side, a shadow was added to the shadowed part at that time Is. In other words, when the east is on the upper side, shading is added so that the topography can be visually recognized correctly.

  In addition, for example, the west background image is assumed to have been irradiated from the southwest, which is the direction located at the upper left when the west is on the upper side, and a shadow is added to the shadowed portion at that time. It is what was done. In other words, when the west is on the upper side, a shadow is added so that the terrain can be visually recognized correctly.

  The image switching unit 105 ′ reads a background image read from the map data storage unit 11b every time the traveling direction of the vehicle is changed between the above three or more directions, according to the changed traveling direction. Switch to. Then, the image switching unit 105 ′ supplies the read background image to the map screen generation unit 102. In response to this, the map screen generation unit 102 generates a map screen based on the background image supplied from the image switching unit 105 ′ and the map data read from the map data storage unit 11 b. As a result, when the traveling direction of the vehicle is changed between the above three or more directions, a map screen in which a shade is added to a portion corresponding to the changed traveling direction is displayed. Will be visible correctly.

  In addition, when the background image of three or more directions is memorize | stored in the map data storage part 11b, when the advancing direction of a vehicle exists between two directions of three or more directions, the image switching part 105 It is preferable to determine which one of the two directions is switched to the background image according to a predetermined rule (for example, the closer one or a predetermined one).

[Example of processing by map screen display device 100c]
FIG. 10 is a flowchart showing an example of processing by the map screen display device 100c according to the fourth embodiment of the present invention. The process illustrated in FIG. 10 is repeatedly executed, for example, when the power of the map screen display device 100c is switched on and until the power of the map screen display device 100c is switched off.

  First, the map screen generation unit 102 reads map data around the vehicle position from the map data storage unit 11b (step S1002). Then, the map screen generation unit 102 determines whether or not to display the map screen in the heading-up mode by referring to the setting information stored in the system memory (step S1004).

  Here, when the map screen generation unit 102 determines that the map screen is not displayed in the heading-up mode (step S1004: No), the image switching unit 105 ′ reads the background image for north from the map data storage unit 11b ( Step S1006). Then, the map screen generation unit 102 uses the map data for the north up mode based on the map data around the vehicle position read in step S1002 and the background image for north read in step S1006. Is generated (step S1008). And the map screen display part 103 displays the map screen produced | generated by step S1008 on the display 13 (step S1016), and the map screen display apparatus 100c complete | finishes a series of processes shown in FIG.

  On the other hand, when the map screen generation unit 102 determines that the map screen is displayed in the heading-up mode (step S1004: Yes), the traveling direction detection unit 101 detects the traveling direction of the vehicle (step S1010). Then, the image switching unit 105 'reads out a background image corresponding to the traveling direction of the vehicle detected in step S1010 from the map data storage unit 11b (step S1012).

  Then, the map screen generation unit 102 uses the map data around the vehicle position read in step S1002 and the background image corresponding to the traveling direction of the vehicle read in step S1012 for heading up. A map screen is generated (step S1014). And the map screen display part 103 displays the map screen produced | generated by step S1014 on the display 13 (step S1016), and the map screen display apparatus 100c complete | finishes a series of processes shown in FIG.

  According to the fourth embodiment, since each of the three or more directions (that is, directions that are finer than the two directions) is provided with a background image that is suitably shaded, the traveling direction of the vehicle However, even if it is changed to any of the above three or more directions, the terrain can be visually recognized more correctly.

  For example, when the background image of eight directions (north, northeast, east, southeast, south, southwest, west, northwest) is stored in the map data storage unit 11b, when the traveling direction of the vehicle is north, A north background image is read from the map data storage unit 11b, and a map screen generated using the north background image is displayed on the display 13. Thereby, the topography can be visually recognized correctly.

  Thereafter, when the traveling direction of the vehicle is changed to the northeast, a northeast background image is read from the map data storage unit 11b, and a map screen generated using the northeast background image is displayed on the display 13. . Thereby, the topography can be visually recognized correctly.

  Further, when the traveling direction of the vehicle is changed to the east, an east background image is read from the map data storage unit 11b, and a map screen generated using the east background image is displayed on the display 13. . Thereby, the topography can be visually recognized correctly.

  Note that, in the fourth embodiment, the map data storage unit 11b includes a first background image that is a direction including north, a second background image that is a direction including south, You may make it provide four background images with the background image of each direction used as the boundary of 1 range and 2nd range. Thereby, it is possible to prevent the terrain from becoming difficult to discriminate when the direction serving as the boundary between the first range and the second range is on the upper side. In addition, since the number of background images can be made relatively small, it is possible to suppress storage capacity compression due to the background images. For example, you may make it provide the background image of the non-inversion range demonstrated in 1st Embodiment, the background image of the inversion range, the northeast background image, and the southwest background image. In this case, the terrain is prevented from becoming difficult to distinguish when the northeast or southwest that is the boundary between the non-inversion range and the inversion range is on the upper side with a relatively small number of background images. be able to.

  In each of the above-described embodiments, a background image to which a shadow is added on the assumption that light is irradiated from the upper left direction is used, but the present invention is not limited to this. That is, a background image to which a shadow is added may be used on the assumption that light is irradiated from a direction other than the upper left direction.

  In each of the above embodiments, the boundary between the inversion range and the non-inversion range is set to the northeast and southwest, but the present invention is not limited to this.

  In addition, each of the above-described embodiments is merely an example of a specific example for carrying out the present invention, and the technical scope of the present invention should not be construed in a limited manner. That is, the present invention can be implemented in various forms without departing from the gist or the main features thereof.

DESCRIPTION OF SYMBOLS 11, 11a, 11b Map data storage part 12 Own vehicle position detection apparatus 13 Display 100, 100a, 100b, 100c Map screen display apparatus 101 Travel direction detection part 102 Map screen generation part 103 Map screen display part 104 Shading change part 105,105 'Image switching unit 106 Boundary changing unit 100A Judgment condition storage unit

Claims (14)

A map screen display device that displays a map screen including a background image that can be viewed three-dimensionally by being shaded,
A traveling direction detector for detecting the traveling direction of the vehicle;
When the map screen is displayed in the heading-up mode, the map screen including the background image to which the shade is added in a different manner is displayed according to the traveling direction of the vehicle detected by the traveling direction detection unit. A map screen display device comprising: a map screen display unit. When the traveling direction of the vehicle is changed, further comprising a shade change unit that changes the density value of each pixel in the background image displayed before the change,
The map screen display unit displays the map screen including a background image shaded in the different mode by using a background image whose density value has been changed by the shading change unit. Item 2. The map screen display device according to Item 1. Determination that stores a determination condition in which a non-inversion range that is a direction range that does not invert the density of each pixel in the background image and an inversion range that is a direction range in which the density of each pixel in the background image is inverted A condition storage unit;
When the vehicle traveling direction is changed from the direction in the non-inversion range to the direction in the inversion range, the density change unit calculates the density value of each pixel in the background image displayed before the change. The map screen display device according to claim 2, wherein the map screen display device is reversed. The non-inversion range is a range of directions including north,
The map screen display device according to claim 3, wherein the inversion range is a range in a direction outside the non-inversion range including the south. In the determination condition, the boundary between the non-inversion range and the inversion range is determined to be northeast and southwest,
5. The map screen display device according to claim 4, wherein the shade changing unit regards northeast as the non-inversion range and regards southwest as the inversion range. When the background image for the non-inverted range is displayed, the traveling direction detected by the traveling direction detection unit is a direction that is a boundary between the non-inverted range and the inverted range. , Change the boundary to the inversion range side,
In the case where the background image for the inversion range is displayed, when the advancing direction detected by the advancing direction detection unit is a direction that is a boundary between the non-inversion range and the inversion range, The map screen display device according to claim 3, further comprising: a boundary changing unit that changes the boundary to the non-inversion range side. A background image storage unit that stores the background image that has been shaded in the different modes;
An image switching unit that switches the background image read from the background image storage unit to the background image corresponding to the changed traveling direction when the traveling direction of the vehicle is changed;
The map screen display unit displays the map screen including a background image shaded in the different mode by using the background image after switching by the image switching unit. The map screen display device according to claim 1. Determination that stores a determination condition in which a non-inversion range that is a direction range that does not invert the density of each pixel in the background image and an inversion range that is a direction range in which the density of each pixel in the background image is inverted A condition storage unit;
The background image storage unit stores the background image for the non-inversion range and the background image for the inversion range,
The image switching unit reads the background image read from the background image storage unit for the non-inverted range when the traveling direction of the vehicle changes from the direction in the non-inverted range to the direction in the inverted range. The map screen display device according to claim 7, wherein the background image is switched to the background image for the inversion range. The non-inversion range is a range of directions including north,
The map screen display device according to claim 8, wherein the inversion range is a range in a direction outside the non-inversion range including the south. In the determination condition, the boundary between the non-inversion range and the inversion range is determined to be northeast and southwest,
The map screen display device according to claim 9, wherein the image switching unit regards northeast as the non-inversion range and regards southwest as the inversion range. When the background image for the non-inverted range is displayed, the traveling direction detected by the traveling direction detection unit is a direction that is a boundary between the non-inverted range and the inverted range. , Change the boundary to the inversion range side,
In the case where the background image for the inversion range is displayed, when the advancing direction detected by the advancing direction detection unit is a direction that is a boundary between the non-inversion range and the inversion range, The map screen display device according to claim 8, further comprising a boundary changing unit that changes the boundary to the non-inversion range side. The background image storage unit stores a background image in which a shadow is added to a different part for each of the three or more directions. The background image of each of the three or more directions has the direction on the upper side. The shading is added so that the terrain can be seen correctly when positioned,
The image switching unit reads the background image read from the background image storage unit every time the traveling direction of the vehicle is changed between the three or more directions according to the changed traveling direction. The map screen display device according to claim 7, wherein the map screen display device is switched to an image. The background image storage unit includes a background image of a first range that is a direction including north, a background image of a second range that is a range including south, the first range, and the second range. The map screen display device according to claim 12, further comprising: a background image in a direction that is a boundary with the range of A map screen display method by a map screen display device configured to display a map screen including a background image that can be viewed three-dimensionally by adding a shadow,
A traveling direction detection step in which the traveling direction detection unit of the map screen display device detects the traveling direction of the vehicle
When the map screen display unit of the map screen display device displays the map screen in the heading-up mode, the shadow is added in a different manner depending on the traveling direction of the vehicle detected by the traveling direction detection unit. And a map screen display step for displaying the map screen including the background image.