JP5738442B2 - Map drawing device, navigation device, and map drawing method - Google Patents

Description

  The present invention relates to a map data drawing technique.

  In a map drawing device such as a navigation device, drawing processing of map data to be displayed on a screen is executed using a drawing library (also referred to as “graphics library”). Specifically, the map drawing device draws graphic information such as the coordinate information of each vertex of the drawing target figure (drawing target figure), the line type of the outline of the drawing target figure, and the fill color of the drawing target figure. Get as. Then, the map drawing apparatus draws map data based on the drawing data using a drawing library, and performs screen display using the map data.

  For example, OpenGL (Open Graphics Library) exists as a drawing library for executing drawing processing, and OpenGL has a plurality of drawing methods.

  Regarding which drawing method is used to draw map data among a plurality of drawing methods, Patent Document 1 discloses a method of analyzing drawing data and selecting one drawing method from a plurality of drawing methods. Proposed.

JP 2010-072808 A

  However, in the method described in Patent Document 1, it takes time to analyze drawing data, and there are cases where drawing processing cannot be performed at high speed.

  Therefore, an object of the present invention is to provide a technique capable of performing drawing processing at high speed.

The map drawing apparatus according to the present invention includes drawing data used when drawing a graphic representing an object on a map image, and acquisition means for acquiring object data including drawing attribute values defining a drawing method of the graphic; Based on the drawing means having a plurality of drawing methods for drawing a figure and the drawing attribute information of the drawing target object to be drawn, the drawing target graphic representing the drawing target object from the plurality of drawing methods Selecting means for selecting a drawing technique when drawing the image, wherein the drawing means draws the drawing target figure using the drawing technique selected by the selection means, and the drawing technique includes one of the drawing techniques There are a plurality of figures .

In addition, the navigation device according to the present invention includes an acquisition unit that acquires drawing data used when drawing a graphic representing an object on a map image, a drawing attribute value that defines a drawing method of the graphic, and draws the graphic. Based on the drawing means having a plurality of drawing methods and the drawing attribute information of the drawing target object to be drawn, the drawing target graphic representing the drawing target object is drawn from the plurality of drawing methods. Selection means for selecting a drawing technique at the time, and display control means for outputting a map image including a graphic drawn using the drawing technique selected by the selection means to a display unit, and the drawing technique includes: It is multiple exist for One of the graphic.

The map drawing method according to the present invention includes: a) obtaining drawing data used when drawing a graphic representing an object on a map image, and drawing attribute values defining a drawing method of the graphic; b) A step of selecting a drawing method for drawing a drawing target graphic representing the drawing target object from a plurality of drawing methods based on the drawing attribute value of the drawing target object to be drawn; c) the above b) using the selected rendering method in step, and a step of drawing the drawing target figure, the drawing technique, be multiple exist for one of said graphic.

  According to the present invention, drawing processing can be performed at high speed.

It is a figure which shows the structure of the navigation apparatus which concerns on 1st Embodiment. It is a figure which shows the relationship between the drawing figure drawn on a map, the drawing data used in order to draw a drawing figure, and the drawing attribute value which prescribes | regulates the drawing method at the time of drawing a drawing figure. It is a flowchart which shows drawing operation | movement of a map drawing apparatus. It is a flowchart which shows operation | movement of the map drawing apparatus at the time of performing a triangular division | segmentation drawing process. It is a figure for demonstrating the specific example of a triangular division | segmentation drawing process. It is a flowchart which shows operation | movement of the map drawing apparatus at the time of performing a stencil drawing process. It is a figure for demonstrating the specific example of a stencil drawing process. It is a figure which shows the relationship between a drawing figure and the drawing attribute value of the said drawing figure. It is a figure which shows the relationship between several drawing attribute values and the hardware which performs a drawing process. It is a figure which shows the relationship between a drawing figure and the drawing attribute value of the said drawing figure.

  Each embodiment will be described below with reference to the drawings.

<1. First Embodiment>
[1-1. Constitution]
FIG. 1 is a diagram illustrating a configuration of a navigation device 1 according to the first embodiment. FIG. 2 is a diagram illustrating a relationship between a drawing figure drawn on a map, drawing data used when drawing the drawing figure, and drawing attribute values that define a drawing method when drawing the drawing figure. As the navigation device 1 described in detail in this specification, for example, a car navigation device mounted on a vehicle, a portable information terminal such as a PDA (Personal Digital Assistants), or a mobile phone is assumed.

  As shown in FIG. 1, the navigation device 1 includes a map drawing device 10 </ b> A that draws map data, an I / O interface 13, a storage device 14, and a display unit 15. The map drawing device 10 </ b> A is electrically connected to the storage device 14 and the display unit 15 via the I / O interface 13.

  The storage device 14 includes an optical drive device using an optical disk such as a DVD-ROM as a storage medium, a nonvolatile memory (eg, SSD, flash, etc.), a removable medium (SD card, etc.), a hard disk device, or the like. The storage device 14 stores information (also referred to as “object data”) 140 of each component (object) constituting the map.

  The objects constituting the map (here, the map image) include objects corresponding to features such as roads, buildings, rivers, railroads, etc., and the object data 140 includes graphic drawing data 141 representing each object, And a drawing attribute value 142 that defines a drawing technique for drawing a graphic corresponding to each object. In addition to the objects corresponding to the features, there are objects that do not correspond to the features other than the objects corresponding to the features, and the object data 140 includes graphic drawing data 141 for objects that do not correspond to these features. And a drawing attribute value 142 are included. Examples of objects that do not correspond to features include boundary lines indicating boundaries between prefectures and municipalities, boundary lines indicating boundaries between countries and states, route lines such as airplanes or ships, and contour lines.

  The map drawing device 10 </ b> A reads out such object data 140 from the storage device 14 and generates map data based on the object data 140.

  Here, the drawing data 141 will be described in detail. The drawing data 141 is information related to the shape of the graphic representing the object, and is used when drawing the graphic representing the object. The drawing data 141 includes information such as coordinate information (vertex data) of each vertex of the figure to be drawn, the line type of the outline of the drawing figure, and the fill color of the drawing figure. On the other hand, the drawing attribute value 142 is information (drawing attribute information) for specifying a drawing technique when drawing a graphic representing each object.

  For example, as shown in FIG. 2, when the shape of the drawing figure is “filled triangle”, the drawing data BD1 corresponding to the drawing figure BF1 includes the coordinate information of the three vertices of the drawing figure BF1. , The outline line type of the drawing figure BF1, the fill color of the drawing figure BF1, and information indicating that the drawing figure BF1 is a polygon (polygon) are included. The drawing attribute value 142 of the drawing figure BF1 is a value “1” indicating that drawing is performed using the standard drawing method.

  When the shape of the drawing figure is a “convex polygon”, the drawing data BD2 corresponding to the drawing figure BF2 includes the coordinate information of the vertex of the drawing figure BF2, the line type of the outline of the drawing figure BF2, the drawing Information indicating the fill color of the figure BF2 and the fact that the drawing figure BF2 is a polygon is included. The drawing attribute value 142 of the drawing figure BF2 is a value “3” indicating that drawing is performed using the triangulation drawing method.

  If the shape of the drawing figure is “multi-vertex polygon”, the drawing data BD3 corresponding to the drawing figure BF3 includes the coordinate information of the vertex of the drawing figure BF3, the line type of the outline of the drawing figure BF3, the drawing Information indicating that the fill color of the figure BF3 and that the drawing figure BF3 is a polygon is included. The drawing attribute value 142 of the drawing figure BF3 is a value “4” indicating that drawing is performed using the stencil drawing method.

  When the shape of the drawing figure is “polyline”, the drawing data BD4 corresponding to the drawing figure BF4 includes the coordinate information of the vertices of the drawing figure BF4 and the line type of the outline of the drawing figure BF4. The drawing attribute value 142 of the drawing figure BF4 is a value “2” indicating that drawing is performed using a line drawing method. A polyline is an object composed of a continuous line segment or curve.

  Returning to the description of the configuration of the navigation device 1 (FIG. 1), the display unit 15 is configured using a liquid crystal display (LCD) or an organic EL display, and displays a map image based on the map data drawn by the map drawing device 10A. Display above.

  The map drawing apparatus 10 </ b> A includes a drawing processing unit 11 that performs drawing processing of an object based on the object data 140 and generates map data, and a storage unit 12.

  The drawing processing unit 11 includes at least one of a CPU (Central Processing Unit) and a GPU (Graphics Processing Unit). The drawing processing unit 11 implements various functional units by reading the program 121 stored in the storage unit 12 and executing the program 121.

  Specifically, the drawing processing unit 11 includes a drawing method determining unit 111, a triangulation unit 112, a stencil processing unit 113, a line drawing unit 114, a standard drawing unit 115, a mask creating unit 116, a polygon, The drawing unit 117 and the display control unit 118 are functionally realized. Each functional unit can be realized by either a CPU or a GPU. Here, among the functional units, a drawing technique determining unit 111, a triangulation unit 112, and a standard drawing unit 115 are realized by a CPU, and a stencil processing unit 113. It is assumed that the line drawing unit 114, the mask creating unit 116, and the polygon drawing unit 117 are realized by a GPU. The display control unit 118 is realized by display control hardware.

  The drawing technique determination unit 111 determines a drawing technique for drawing a figure (drawing object figure) representing a drawing object to be drawn. Specifically, the drawing technique determination unit 111 acquires the object data 140 from the storage device 14. Then, the drawing method determination unit 111 determines a drawing method for each drawing target graphic based on the drawing attribute value 142 for each drawing target graphic.

  The map drawing apparatus 10A uses, as drawing methods, a triangulation drawing method using OpenGL, a stencil drawing method and a line drawing method, and a standard drawing method (standard drawing method) other than the drawing method using OpenGL. Have. The drawing technique determination unit 111 functions as a selection unit that selects a drawing technique of a drawing target graphic from these drawing techniques. Details of each drawing method will be described later.

  The triangulation unit 112 is a functional unit realized by a software part using OpenGL. The triangle dividing unit 112 repeats the process of drawing a diagonal line from one vertex (point of interest) in the drawing target graphic toward the other stacked vertices while changing the vertex, thereby changing the drawing target graphic into a plurality of triangles. The drawing target area is specified by dividing into two. Data indicating the drawing target area is output to the polygon drawing unit 117. It should be noted that the triangle dividing unit 112 outputs data related to each divided triangle to the polygon drawing unit 117 as data indicating the drawing target area.

  The stencil processing unit 113 is a functional unit realized using OpenGL. The stencil processing unit 113 forms a triangle by drawing a line segment from a certain vertex in the drawing target graphic to each of the other vertices, and specifies a drawing target region according to the number of overlaps of the formed triangles. Data indicating the drawing target area is output to the mask creating unit 116 as stencil data.

  The line drawing unit 114 is a functional unit realized using OpenGL, and has a function of drawing a line figure as a drawing target figure in a frame memory (not shown) such as a VRAM by a line drawing method. Yes. Line drawing methods using OpenGL include drawing a line figure using a finite straight line (segment) (also called “continuous line drawing method”) and drawing a line figure by arranging multiple points. (Both the method of drawing continuous points with OpenGL and the method of giving points continuously from the software part using OpenGL are also referred to as “continuous point drawing method” herein). The drawing method determination unit 111 selects whether to draw a line drawing target figure using the continuous point drawing method or the continuous line drawing method based on the drawing attribute value 142.

  The standard drawing unit 115 is a functional unit realized by executing standard drawing software other than OpenGL by a CPU (or GPU), or a processing unit realized in a drawing chip mounted on the map drawing apparatus 10A. is there. The standard drawing unit 115 draws the drawing target graphic in the frame memory by a standard drawing method. According to the standard drawing method, it is possible to draw a drawing target figure with a small amount of calculation, compared to a drawing method using OpenGL realized by the triangulation unit 112, the stencil processing unit 113, and the line drawing unit 114.

  The mask creation unit 116 creates a mask pattern based on the stencil data input from the stencil processing unit 113 and stores the mask pattern in the stencil buffer 119.

  Here, the mask pattern restricts the drawing part of the figure to a specific part. With this mask pattern, even if the entire figure is filled, only the drawing target portion can be drawn.

  The polygon drawing unit 117 draws a drawing target figure in the frame memory and generates map data. More specifically, the polygon drawing unit 117 draws the outline of the drawing target graphic in the frame memory based on the data indicating the drawing target region input from the triangulation unit 112 and draws based on the drawing data 141. Fills the target figure. Further, the polygon drawing unit 117 draws a drawing target graphic on the frame memory using the mask pattern and the drawing data 141 stored in the stencil buffer 119.

  The display control unit 118 controls display contents on the display unit 15. Specifically, the display control unit 118 performs map image display processing using map data formed in the frame memory.

[1-2. Operation]
Next, a drawing operation executed in the map drawing apparatus 10A will be described. FIG. 3 is a flowchart showing the drawing operation of the map drawing apparatus 10A.

  As shown in FIG. 3, first, in step SP1, the drawing processing unit 11 reads out and acquires object data 140 necessary for map display from the storage device.

  In the next step SP2, the drawing technique determination unit 111 determines a drawing technique for drawing a graphic representing the drawing target object based on the drawing attribute value 142 of the drawing target object.

  Each value given as the drawing attribute value 142 has a one-to-one correspondence with each drawing method, and the drawing method determination unit 111 uses the drawing attribute value 142 of the drawing target object to draw a drawing target graphic. A drawing method can be uniquely identified.

  In the next step SP3, the drawing process related to the drawing target graphic is performed using the drawing method determined in step SP2. For example, when the triangulation drawing technique is selected as the drawing technique for the drawing target graphic in step SP2, a drawing process using the triangulation drawing technique is performed in step SP3. For example, when the standard drawing technique is selected as the drawing technique for the drawing target graphic in step SP2, the drawing process using the standard drawing technique is performed in step SP3.

  When the drawing process ends in step SP3, the operation process moves to step SP4.

  In step SP4, it is determined whether there is an undrawn object that has not been drawn.

  If there is no undrawn object, the drawing operation ends.

  On the other hand, when there is an undrawn object, the operation process moves to step SP1, and each process from step SP1 to step SP4 is executed again with the undrawn object as the drawing target object. Each process of step SP1 to step SP4 is repeatedly executed until there is no undrawn object by the determination process of step SP4.

[1-3. About drawing method]
Here, a triangulation drawing method provided in the map drawing apparatus 10A of the present embodiment will be described. FIG. 4 is a flowchart showing the operation of the map drawing apparatus 10A when performing drawing processing (triangular division drawing processing) using the triangulation drawing method. FIG. 5 is a diagram for explaining a specific example of the triangulation division drawing process. In FIG. 5, a polygon is shown as a drawing target graphic.

As shown in FIG. 4, first, in step SP11, each vertex in the drawing target graphic is sorted in descending order of the Y-axis coordinates. For example, in FIG. 5, the vertices of the polygon to be drawn are rearranged in the order of vertices C ₁ , C ₂ , C ₃ , C ₄ , C ₅ , C ₆ , and C ₇ .

In step SP12, vertices corresponding to two vertices from the top of each sorted vertex are stacked. In Figure 5, so that the vertex _{C 1} and vertex _{C 2} are stacked.

In step SP13, among the sorted vertices, the third vertex from the top is set as the attention point _Pn . In FIG. 5, the vertex C ₃ is set to the attention point P ₃ .

In step SP14, a diagonal line is drawn from the attention point Pn to the stacked vertices. For example, in FIG. 5, a diagonal line is drawn from the attention point P ₃ (vertex C ₃ ) to the stacked vertex C ₂ .

In the next step SP15, it is determined whether or not the entire drawing target graphic is divided into triangles. When it is determined that the entire drawing target figure is divided into triangles, the triangulation drawing process ends. On the other hand, when it is determined that the entire drawing target figure is not divided into triangles, the operation process proceeds to step SP16. For example, in the example of FIG. 5, since there is a polygon C ₂ C ₃ C ₄ C ₅ C ₆ C ₇ that cannot be divided into all triangles, the operation process is shifted to step SP16.

  In step SP16, vertices that are not divided into triangles are stacked. In FIG. 5, vertices C4, C5, C6, and C7 are stacked.

In step SP17, the point of interest _Pn is shifted by one. In Figure 5, it will be set the target point C ₃ to shifted by one C _4.

Then, in step SP14 is executed again, the diagonal can be formed on the inside of the object shape toward the vertex C _5, C _6, C ₇ newly stacked from a new point of interest C ₄ is subtracted become.

In step SP15, it is determined again whether or not the entire drawing target graphic is divided into triangles. In the example of FIG. 5, since there is a polygon C ₂ C ₃ C ₅ C ₄ that cannot be divided into all triangles, the operation process moves to step SP16 again.

In step SP16, the vertices C ₂ and C _{3 that} are not divided into triangles are stacked.

In step SP17, the point of interest _Pn is shifted by one. In Figure 5, is set the target point _{C 4} to _{C 5} are shifted by one.

In step SP14, the retraction of the diagonal can be formed on the inner side of the polygon towards the new target point C ₅ to the vertex C _2, C ₃ newly stacked.

  In step SP15, it is determined again whether or not the entire drawing target figure has been divided into triangles. In the example of FIG. 5, since all the drawing target figures can be divided into triangles, the triangle division drawing process ends.

  In this way, in the triangle division drawing process, the drawing target area is specified by dividing the entire drawing target figure into triangles.

  Next, a stencil drawing method provided in the map drawing apparatus 10A will be described. FIG. 6 is a flowchart showing the operation of the map drawing apparatus 10A when drawing processing (stencil drawing processing) is performed using the stencil drawing method. FIG. 7 is a diagram for explaining a specific example of the stencil drawing process. In FIG. 7, a star-shaped polygon RF (RF1 to RF6) is shown as a drawing target graphic. The six polygons RF1 to RF6 in FIG. 7 are for explaining according to the progress of the stencil drawing process, and these polygons RF1 to RF6 are the same polygon RF.

As shown in FIG. 6, first, in step SP21, the top vertex among the vertices of the drawing target graphic is registered as the start point Pf. For example, in Figure 7, the vertex D ₁ leading out of the vertices of the polygon RF is registered as the start point Pf.

In step SP22, a triangle is formed by drawing a line segment from the start point Pf registered in step SP21 to each other vertex. In FIG. 7, a line segment is drawn from the start point D ₁ to each of the other vertices D _{2 to} D ₁₀ . Accordingly, in the polygon RF, the triangle “D ₁ D ₂ D ₃ ” (see the polygon RF ₁ ), the triangle “D ₁ D ₃ D ₄ ” (see the polygon RF 2), the triangle “D ₁ D ₅ D ₆ ” ( Referring polygon RF3), see triangle _"D 1 _D 6 _{D 7"} (polygon RF4), triangle _"D 1 _D 8 _{D 9"} (see polygonal RF5), and triangles _"D 1 _D 9 _{D 10"} (multi A square RF6 is formed).

In step SP23, a portion where the triangle formed in step SP22 overlaps an odd number of times is set as a drawing target area. In FIG. 7, the non-renderable areas of the triangles formed in step SP22 that overlap the odd number of times, that is, the triangles “D ₁ D ₂ D ₃ ” and “D ₁ D ₉ D ₁₀ ” where the triangles overlap the even number of times. All the other triangles except the above are set as the drawing target area.

  As described above, in the stencil drawing process, the star-shaped drawing region indicated by the polygon RF6 can be obtained by executing the steps SP21 to SP23.

  As described above, the map drawing apparatus 10A according to the present embodiment includes object data 140 including drawing data 141 used when drawing a graphic representing an object on a map image and a drawing attribute value 142 defining a drawing method of the graphic. A plurality of drawing methods based on drawing means having a plurality of drawing methods for drawing a figure and drawing attribute information 142 of a drawing target object to be drawn. And a drawing method determination unit 111 that selects a drawing method for drawing a drawing target graphic representing an object. Then, the map drawing apparatus 10A draws the drawing target figure using the drawing method selected by the drawing method determination unit 111.

  According to such a map drawing apparatus 10A, since a drawing method can be selected based on the drawing attribute value 142, it is possible to reduce the time required for selecting the drawing method, and thus speed up the drawing process. Can be achieved. In addition, since an appropriate drawing method can be selected according to the shape of the linear drawing target figure, the time required for drawing can be shortened, and the drawing process can be speeded up.

<2. Second Embodiment>
Next, a second embodiment will be described. The map drawing apparatus 10B according to the second embodiment has substantially the same structure and structure as the map drawing apparatus 10A of the first embodiment, except that the drawing technique determination mode using the drawing attribute value in the drawing technique determination unit 111 is different. The common portions are denoted by the same reference numerals, and description thereof is omitted.

  As described above, in the map drawing apparatus 10B, the drawing technique determination mode using the drawing attribute value in the drawing technique determination unit 111 is different from the map drawing apparatus 10A of the first embodiment. Specifically, in the second embodiment, there are a plurality of drawing attribute values for one drawing target graphic, and the map drawing apparatus 10B selects a drawing method using a drawing attribute value suitable for itself. FIG. 8 is a diagram illustrating a relationship between a drawing figure and a drawing attribute value of the drawing figure. FIG. 9 is a diagram illustrating a relationship between a plurality of drawing attribute values and hardware that performs drawing processing.

  More specifically, as shown in FIG. 8, the object data 140 of the second embodiment may have a plurality (two in this case) of drawing attribute values as drawing attribute values of the drawing target graphic. is there. For example, the drawing attribute value of the drawing figure BF2 includes a first drawing attribute value “3” and a second drawing attribute value “1”. The value “3” is a value indicating that drawing is performed using the triangulation drawing method, and the value “1” is a value indicating that drawing is performed using the standard drawing method.

  The triangulation drawing method is a drawing method that requires a large amount of calculation compared to the standard drawing method. Therefore, the first drawing attribute value “3” indicating that drawing is performed using the triangulation drawing method is a drawing attribute value for a map drawing apparatus (first hardware) having a relatively high drawing processing capability. . On the other hand, the second drawing attribute value “1” indicating that drawing is performed using the standard drawing technique is a drawing attribute value for a map drawing apparatus (second hardware) having a relatively low drawing processing capability.

  The drawing method determination unit 111 of the map drawing apparatus 10B acquires hardware information (hardware information) for performing drawing processing in the map drawing apparatus 10B when there are a plurality of drawing attribute values of the drawing target graphic. Then, the drawing technique determination unit 111 selects a drawing attribute value suitable for the map drawing apparatus 10B from a plurality of drawing attribute values based on the hardware information.

  For example, as shown in FIG. 9, object data is used as a drawing attribute value for the map drawing apparatus 10Q having a relatively high drawing processing capability in which the first drawing attribute value “3” of the drawing figure BF2 includes a CPU and a GPU. 140, the second drawing attribute value “1” is included in the object data 140 as a drawing attribute value for the map drawing apparatus 10R having a relatively low drawing processing capability that does not have a GPU.

  At this time, when the map drawing device 10B is the first map drawing device 10Q having a relatively high drawing processing capability, the drawing method determination unit 111 selects the first drawing attribute value “3”, and the first drawing attribute value “3” is selected. The drawing method is determined using the drawing attribute value. As a result, the drawing target figure BF2 is drawn using the triangulation drawing technique.

  On the other hand, when the map drawing device 10B is the second map drawing device 10R having a relatively low drawing processing capability, the drawing method determination unit 111 selects the second drawing attribute value “1”, and A drawing technique is determined using the second drawing attribute value. As a result, the drawing target figure BF2 is drawn using the standard drawing method.

  As described above, the drawing method determination unit 111 determines whether the hardware for performing the drawing process is the first hardware having a relatively high drawing processing capability or the second hardware having a relatively low drawing processing capability. A determination is made, and a drawing attribute value used for selecting a drawing method is determined based on the determination result. Then, the drawing technique determination unit 111 selects the drawing technique defined by the determined drawing attribute value as a drawing technique for drawing the drawing target graphic.

  According to this, since it is possible to draw a figure by adopting an appropriate drawing method according to the drawing processing capability of the map drawing apparatus 10B, it is possible to reduce the time required for drawing, and the drawing process Can be speeded up.

<3. Third Embodiment>
Next, a third embodiment will be described. The map drawing apparatus 10C according to the third embodiment has substantially the same structure and the same structure as the map drawing apparatus 10A of the first embodiment, except that the drawing technique determination mode using the drawing attribute value in the drawing technique determination unit 111 is different. The common portions are denoted by the same reference numerals, and description thereof is omitted.

  As described above, in the map drawing apparatus 10C, the drawing technique determination mode using the drawing attribute value in the drawing technique determination unit 111 is different from the map drawing apparatus 10A of the first embodiment.

  Specifically, in the third embodiment, there are a plurality of drawing attribute values that stipulate that the triangulation drawing method is adopted. The plurality of drawing attribute values are also referred to as specific drawing attribute values, and a specific drawing attribute value having a large value is assigned to a complicated drawing target graphic. That is, as the drawing target figure becomes complex, the value of the specific drawing attribute value increases.

  For example, it is assumed that a plurality of specific drawing attribute values that define the use of the triangulation drawing method are represented by eight integers from “3” to “10”. In this case, as shown in FIG. 10, the specific drawing attribute value “3” is given to the drawing attribute value of the relatively simple drawing figure BF11, and the drawing attribute value of the relatively complicated drawing figure BF15 is A specific drawing attribute value “10” is given.

  The drawing method determination unit 111 of the map drawing apparatus 10C, when the drawing attribute value of the drawing target figure is a specific drawing attribute value, represents a hardware performance value obtained by quantifying the performance of the hardware that performs the drawing process in the map drawing apparatus 10C. To get. Then, when the hardware performance value is equal to or higher than the specific drawing attribute value of the drawing target graphic, the drawing method determining unit 111 uses the triangulation drawing method as a drawing method when drawing the drawing target graphic according to the definition of the specific drawing attribute value. select. On the other hand, when the hardware performance value is smaller than the specific drawing attribute value of the drawing target figure, the drawing method determining unit 111 uses the stencil drawing method to draw the drawing target figure against the definition of the specific drawing attribute value. Select as drawing method.

  For example, when the hardware performance value of the map drawing apparatus 10C is “6”, all of the drawing figures BF11, BF12, and BF13 having a specific drawing attribute value equal to or lower than the hardware performance value use the triangulation drawing method. Will be drawn. On the other hand, the drawing figures BF14 and BF15 having a specific drawing attribute value larger than the hardware performance value are both drawn using the stencil drawing method.

  As described above, by determining the drawing method in consideration of the performance of the hardware that performs the drawing process and the complexity of the drawing target figure, it is optimal for the hardware performance and the shape of the drawing target figure. It is possible to select a suitable drawing method with high accuracy. As described above, since the accuracy of selecting the drawing technique is increased, the time required for the drawing process can be shortened, and the drawing process can be speeded up.

  Note that the hardware performance value is a function whose variables are the number of clocks of the CPU and the GPU of the map drawing apparatus 10C and / or the type of the CPU and the GPU, and the drawing method determination unit 111 includes the CPU and the CPU of the own apparatus. A hardware performance value is calculated based on the GPU information.

  The complexity of the drawing target graphic can be determined based on, for example, the number of vertices of the drawing target graphic, and the drawing target graphic having a large number of vertices is a complex graphic.

<4. Modification>
Although the embodiments have been described above, the present invention is not limited to the contents described above.

  For example, in each of the above-described embodiments, the map drawing devices 10A and 10B having the triangulation drawing method are illustrated as the drawing method, but the map drawing devices 10A and 10B of each embodiment are replaced with the triangulation drawing method. You may make it the aspect which has a trapezoid division | segmentation drawing method.

  In the trapezoidal split drawing method, the process of drawing a diagonal line from one vertex (point of interest) in the drawing target graphic toward the other stacked vertices is repeated while changing the vertices. The drawing target area is specified by dividing into two.

  In the second embodiment, the case where the object data 140 has two drawing attribute values for one drawing target graphic is exemplified. However, the number of drawing attribute values is three for one drawing target graphic. There may be more than one.

  For example, a drawing attribute value may be provided according to the number of combinations of CPUs and GPUs of each map drawing apparatus assumed to use the object data 140. Specifically, it is assumed that the object data 140 is used for three types of map drawing devices, and the combination of CPU and GPU is different in each of the three types of map drawing devices. In this case, the object data 140 may have three drawing attribute values that define drawing methods applicable to each of the three types of map drawing devices as drawing attribute values of one drawing target graphic.

  In this case, the drawing technique determination unit 111 of the map drawing apparatus 10B acquires information on the CPU and GPU provided in the map drawing apparatus 10B, and sets the drawing attribute value used for selecting the drawing technique based on the information to 3 One drawing attribute value is selected.

  According to such a map drawing apparatus 10B, it is possible to draw a figure by employing an appropriate drawing method according to the drawing processing capability of the map drawing apparatus 10B, so that the time required for drawing can be shortened. Thus, the drawing process can be speeded up.

  In each of the above embodiments, the case where the line drawing method using OpenGL includes the continuous point drawing method and the continuous line drawing method is exemplified, but the standard line drawing method other than the line drawing method using OpenGL is used. Alternatively, the continuous point drawing method and the continuous line drawing method may be included.

  Within the scope of the invention, the present invention can be freely combined with each embodiment, modified with any component in each embodiment, or omitted with any component in each embodiment.

  DESCRIPTION OF SYMBOLS 1 Navigation apparatus, 10A, 10B, 10C Map drawing apparatus, 11 Drawing process part, 12 Memory | storage part, 14 Memory | storage device, 15 Display part, 111 Drawing method determination part, 112 Triangulation part, 114 Line drawing part, 117 Polygon drawing Part, 118 display control part, 140 object data, 141 drawing data, 142 drawing attribute value

Claims (11)

Acquisition means for acquiring drawing data used when drawing a graphic representing an object on a map image and drawing attribute values defining a drawing method of the graphic;
Drawing means having a plurality of drawing methods for drawing the figure;
Based on the drawing attribute information of the drawing target object to be drawn, a selection means for selecting a drawing method for drawing a drawing target graphic representing the drawing target object from the plurality of drawing methods;
With
The drawing means draws the drawing target figure using the drawing method selected by the selection means ,
There are a plurality of map drawing apparatuses that exist for one figure . The drawing means includes the plurality of drawing methods,
A polygon drawing method used when drawing a polygonal figure as the drawing target figure;
And map drawing device according to claim 1 having a standard drawing our method drawable the drawing object graphic with a small amount of calculation as compared with the polygon rendering our method. The drawing means includes the plurality of drawing methods,
A line drawing technique used when drawing a line figure as the drawing target figure;
The said line drawing techniques, according to claim 1 that contains a continuous point drawing technique by arranging a plurality of points drawing shapes of the linear and continuous line drawing technique for drawing the wire-like shape using a finite straight line Map drawing device. The polygon drawing method includes:
A triangulation drawing method for drawing the drawing target figure by dividing the drawing target figure into a plurality of triangles based on vertex data of the drawing target figure included in the drawing data and specifying a drawing target area; ,
Based on the vertex data, a line segment is drawn from one vertex in the drawing target graphic to each other vertex to form a triangle, and the drawing target region is specified according to the number of overlaps of each formed triangle. A stencil drawing method for drawing the drawing target figure,
The map drawing apparatus according to claim 2 , including: The drawing attribute value, the map drawing device according to claim 2, the values for identifying the standard drawing our method and our the polygon rendering our method is present.   The map drawing apparatus according to claim 4, wherein the drawing attribute value includes two values for specifying the triangulation drawing method and the stencil drawing method. The object data includes, as the drawing attribute value, a first drawing attribute value indicating a drawing method when drawing is performed on first hardware, and a second drawing method indicating a drawing method when drawing is performed on second hardware. A drawing attribute value for each figure,
The acquisition means acquires the first drawing attribute value and the second drawing attribute value,
The selection unit determines whether the hardware for drawing the graphic is the first hardware or the second hardware, and uses it for selecting a drawing method based on the determination result. The map drawing apparatus according to claim 1, wherein a drawing attribute value is selected from the first drawing attribute value and the second drawing attribute value. The object data has a plurality of drawing attribute values for each figure depending on the number of the combinations, which define a drawing method adapted to a combination of a CPU and a GPU that perform drawing processing,
The acquisition means acquires each drawing attribute value according to the number of the combinations,
The said selection means acquires the information of CPU and GPU used for the drawing process of the said figure, and selects the drawing attribute value used for selection of a drawing method from each said drawing attribute value based on the said information The map drawing apparatus according to 1. The drawing attribute value includes a plurality of specific drawing attribute values indicating that the triangulation drawing method is adopted,
As the drawing target figure becomes complex, a drawing attribute value of the drawing target figure is assigned a specific drawing attribute value having a larger value among the plurality of specific drawing attribute values,
The selection unit obtains a hardware performance value obtained by quantifying the performance of hardware that performs drawing, and when the hardware performance value is equal to or greater than a specific drawing attribute value of a drawing target graphic, the triangulation drawing method is used as the drawing method. The drawing method is selected as a drawing method for drawing the target graphic, and when the hardware performance value is smaller than the specific drawing attribute value of the drawing target graphic, the stencil drawing method is selected as a drawing method for drawing the drawing target graphic. Item 2. The map drawing device according to Item 1. Obtaining means for obtaining drawing data used to draw a graphic representing an object on a map image, and a drawing attribute value defining a drawing method of the graphic;
Drawing means having a plurality of drawing methods for drawing the figure;
Based on the drawing attribute information of the drawing target object to be drawn, a selection means for selecting a drawing method for drawing a drawing target graphic representing the drawing target object from the plurality of drawing methods;
Display control means for outputting a map image including a graphic drawn using the drawing technique selected by the selection means to a display unit;
Equipped with a,
The drawing technique, the navigation device be multiple exist for one of said graphic. a) obtaining drawing data used when drawing a graphic representing an object on a map image, and drawing attribute values defining a drawing method of the graphic;
b) selecting a drawing method for drawing a drawing target graphic representing the drawing target object from among a plurality of drawing methods based on the drawing attribute value of the drawing target object to be drawn;
c) drawing the drawing target figure using the drawing method selected in the step b);
Equipped with a,
The drawing method, a map drawing how to more exist for one of said graphic.

Images