JP3029554B2 - 3D graphic drawing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional graphic drawing apparatus capable of detecting a positional relationship between three-dimensional objects at a high speed without imposing a burden on a CPU.

[0002]

2. Description of the Related Art In a conventional three-dimensional figure drawing apparatus, a drawing control unit converts geometric data described in an object coordinate system into a CPU.
And performs a coordinate conversion operation for converting it into a viewpoint coordinate system, and further projects it two-dimensionally and outputs it as a drawing. On the other hand, in game software or the like, for example, in order to detect a positional relationship between objects in a three-dimensional space (viewpoint coordinate system) and determine collision between the objects, the CPU performs coordinate conversion similar to the above. Performs calculations (mainly matrix product calculations).

[0003]

However, in the conventional three-dimensional graphic drawing apparatus, the operation of coordinate transformation for detecting the positional relationship between objects in the three-dimensional space is relatively complicated, so that the performance of the conventional three-dimensional graphic drawing apparatus is low. The burden on the low CPU is heavy, and it was not possible to detect collision between objects at high speed. Obedience
Therefore, an object of the present invention is to quickly determine a collision between three-dimensional objects.
And a three-dimensional figure drawing device that can accurately detect
To provide.

[0004]

The present invention achieves the above objects.
To represent multiple 3D objects in the object coordinate system.
N coordinate data (x1, y1, z1) to (xn, y
n, zn) and input n coordinate data (x
1 ', y1', z1 ') to (xn', yn ', zn')
A geometric processing unit, and the n coordinate data subjected to coordinate conversion
And input the n pieces of coordinate data for each of x, y, and z coordinate values.
The comparison circuit that compares the magnitude and the comparison circuit
And maximum values for each x, y, z coordinate value obtained
And a register for recording x,
Read the minimum and maximum values for each y, z coordinate value
The minimum and maximum values for each of the read x, y, and z coordinate values
A plurality of three-dimensional objects each surrounding the plurality of three-dimensional objects by a value
Forming a boundary area, the relative positions of the plurality of three-dimensional boundary areas;
First between the plurality of three-dimensional objects corresponding to the
A collision determination is made and a collision occurs in the first collision determination.
When it is determined that the three-dimensional object
A plurality of divided 3D boundary areas each surrounding a divided 3D object
Is formed, and a plurality of divided three-dimensional objects of another three-dimensional object are formed.
And a plurality of divided three-dimensional boundary regions formed respectively.
Collision determination means for performing a second collision determination between
And a three-dimensional figure drawing apparatus characterized by the following.

[0005]

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a three-dimensional graphic drawing apparatus according to the present invention will be described below. FIG. 1 shows the configuration of the present apparatus, including a CPU 1, a bus interface 2, a geometric processing unit 3, a comparison circuit 4, a register 5, a dot drawing unit 6, a frame memory 7, a CRT
Eight.

In a normal drawing operation of the present apparatus, CP
U1 outputs image data including the coordinates and colors of polygons or sprites to the geometric processing unit 3 via the bus interface 2. The geometric processing unit 3 converts the input image data from object coordinates to viewpoint coordinates and then draws dots. The converted data is output to the unit 6, and then the data for each dot is output from the dot drawing unit 6 and written into the frame memory 7,
An image signal is formed by a video encoder (not shown) to form a predetermined image on the CRT 8.

Here, when it is necessary to check the positional relationship between the objects in the present apparatus, first, the CPU 1 issues a "Vertex test" command for detecting the positional relationship, and outputs the shape data of the actual object. Separately, a bounding box (in the object coordinate system) of the object is formed in advance, and n (eg, 4, 6, 8) vertex coordinate data (x1, y1, z1) to (xn, yn, zn) Is input to the geometric processing unit 3. This "Vertex test" command may be issued any number of times, and the object whose collision is to be determined (for example,
If there are a plurality of airplanes and bullets, the command and vertex coordinate data may be output to the geometric processing unit 3 for each of those objects.
Further, the bounding box formed in advance may be any box that can include all the dots constituting the object.

The geometric processing unit 3 performs a "Vertex test"
When a command is input, the vertex coordinate data input together with the command is converted in the same manner as the normal coordinate conversion from the object coordinates to the viewpoint coordinates, and the converted coordinate data (x1 ', y1', z
1 ') to (xn', yn ', zn') are output to the comparison circuit 4.
In this embodiment, when the “Vertex test” command is input, the geometric processing unit 3 outputs the result of the coordinate conversion to the comparison circuit 4, but in other embodiments, when the “Vertex test” command is input, The result of the conversion is output to the dot drawing section 6 while being output to the comparison circuit 4, so that an actual object can be drawn and a bounding box can be formed. In the case of this embodiment, "Vertex
Along with the “test” command, the same number of vertex coordinate data as the shape data of the actual object subjected to the normal drawing operation is input to the geometric processing unit 3. All the data is output to the dot drawing unit 6, while the comparison circuit 4 outputs a part of the coordinate-converted coordinate data (that is, a smaller number of data than the minimum required to form the bounding box of the object). Coordinate data can also be specified).

In the comparison circuit 4, a predetermined number of coordinate data (x
1 ', y1', z1 ') to (xn', yn ', zn') are compared for each of the x, y, and z coordinates in the order of input, and larger and smaller coordinate values are obtained. Is written to the register 5. FIG. 2 shows a flowchart for comparing certain coordinate values x ′, y ′, z ′ in the comparison circuit 4.
Each coordinate value is updated or held in comparison with the minimum value and the maximum value previously written in the register 5. When all such comparisons are completed, the maximum value xma of the x coordinate value is obtained.
x, minimum value xmin, maximum value ymax of y coordinate value, minimum value ymi
The maximum value zmax and the minimum value zmin of the n and z coordinate values are written in the register 5, respectively. Note that the CPU is "Verte
When issuing the “x test” command, the xmi
For n, ymin, and zmin, the maximum values are xmax, ymax, and zmax.
Is written with each minimum value as an initial value.

Next, the CPU 1 reads xma from the register 5.
x, xmin, ymax, ymin, zmax, zmin are read out, and a bounding box surrounded by these six coordinate values is formed. This bounding box represents a minimum three-dimensional boundary area including all vertex coordinates constituting an object. Therefore, in order to detect the positional relationship between the objects, it is only necessary to form the respective bounding boxes by the above-described procedure and check the positional relationship (overlap or the like) between the bounding boxes.

The bounding box may be formed not only for the region surrounding the whole object but also for a region that partially covers the object. In this case, the coordinates of the part of the object in the object coordinate system may be set in advance. The data (bounding box data) is provided to the geometric processing unit 3 together with the "Vertex test" command, and the maximum value and the minimum value after the coordinate conversion are written in the register 5 to form a bounding box in the same manner as the above procedure.

Here, for example, consider a case in which a collision between the airplane A and the airplane B is determined. First, the CPU 1 executes the “Vertex” command according to the above-described procedure to form a bounding box surrounding the entire plane A and a bounding box surrounding the entire plane B. As shown in FIG. Find out. If the two bounding boxes do not overlap, Airplane A and Airplane B have not collided.

On the other hand, if the two bounding boxes overlap, there is a possibility that the plane A and the plane B have collided. However, since these bounding boxes are rough ones that surround the entire plane, they are partially If you look, you may not be in collision. Therefore, as shown in FIG. 3, a more accurate bounding box is formed by further dividing each airplane portion (the fuselage, the wing, and the tail).
(2.1)-(2.6) and further (3.1)-
Perform the test in (3.9). Each of these collision tests can be selected as needed, for example, the test of (1) can be omitted and the test of (2.1) can be started. Also, starting from the test of (1), (2.1)-
(2.6) can be omitted, and a collision can be determined by sequentially performing nine tests (3.1) to (3.9). Alternatively, it is also possible to omit the tests (1) and (2.1) to (2.6) and to immediately perform nine tests (3.1) to (3.9) in order to determine the collision. . Generally, a method of starting with a rough test first and subdividing the test as necessary is used as in (1).

[0015]

As described in detail above, according to the three- dimensional graphic drawing apparatus of the present invention, the three- dimensional boundary
A first collision determination is performed using the boundary region, and a first collision determination is performed.
Divides a 3D object when it is determined that there is a collision
Using the divided three-dimensional boundary region for the divided three-dimensional object
Since the second collision determination is performed, the collision between the three-dimensional objects is performed.
It is possible to quickly and accurately detect a collision determination.

Therefore, even a low-performance CPU can calculate the position information between objects at a higher speed by using the calculation result of the geometric processing unit.

[Brief description of the drawings]

FIG. 1 shows a configuration example of a three-dimensional graphic drawing apparatus according to the present invention.

FIG. 2 is a flowchart illustrating an example of comparison control in a comparison circuit.

FIG. 3 is a flowchart illustrating an example of a collision determination.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G06T 15/00-17/40 A63F 13/00

Claims (2)

(57) [Claims] An n coordinate data (x1, y1, z1) to (xn, y) expressed in an object coordinate system for a plurality of three-dimensional objects.
n, zn) and input n coordinate data (x
1 ', y1', z1 ') to (xn', yn ', zn'), a geometric processing unit, and the n coordinate data which has been subjected to the coordinate conversion is input and the n coordinate data is input. A comparison circuit that compares the coordinate data for each of the x, y, and z coordinate values; a register that records a minimum value and a maximum value for each of the x, y, and z coordinate values obtained by the comparison circuit; The minimum and maximum values for each of the x, y, and z coordinate values recorded in the register are read, and the read x, y, and
minimum value for each z coordinate values and the maximum value of the plurality of three-dimensional objects to form a plurality of three-dimensional boundary area surrounding each before the corresponding based on the relative position of the <br/> plurality of three-dimensional boundary area
Together Doing first collision determination between serial plurality of three-dimensional objects
If it is determined in the first collision determination that there is a collision,
A plurality of divided 3D objects obtained by dividing a 3D object.
Forming a plurality of divided three-dimensional boundary areas, each surrounding
Each of the three-dimensional objects divided from the original object is formed
Determination of collision with a plurality of divided three-dimensional boundary areas
3D graphics-rendering apparatus characterized by comprising a collision judging means for performing. 2. The geometric processing unit outputs the coordinate-transformed n coordinate data to a dot drawing unit that generates image data for each dot based on the n coordinate data, and outputs the coordinate-converted n coordinate data. 2. The three-dimensional figure drawing apparatus according to claim 1, wherein at least a part of the coordinate data is output to the comparison circuit.