JPH0243691A - Input/output converting segment memory and hidden-surface processor - Google Patents

Abstract

PURPOSE:To easily and promptly control a segment by executing a segment input in units of a polygon and a segment output in units of a scanning line by means of an address control and a memory. CONSTITUTION:A row write address counter 30 outputs and updates a write address, a column write address register 33 and an incrementor 35 output and update a column write address on the row, and successively write segment data in units of a polygon into a designated memory cell in a memory cell array 38. On the other hand, the row read address is outputted and updated by a row read address counter 41, and the segment data for one row are stored from the memory cell array 38 into a data register 42, the column address is outputted and updated by a column read address counter 40, and the segment data in units of a scanning line are successively outputted from the data register 42. Thus the segment can be easily and promptly controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a hidden surface processing device in a three-dimensional computer graphics device that projects and displays a three-dimensional polyhedral object on a two-dimensional screen while performing hidden surface processing. It is.

Conventional Technology When displaying a composite of three-dimensional objects on a two-dimensional screen, it is necessary to somehow handle the phenomenon in which objects in the foreground partially or completely hide objects in the background. The color and brightness of each pixel must be output to the display device in raster scan order. Such a three-dimensional graphics device generally has a configuration as shown in FIG.

First, the coordinate conversion/perspective conversion device 11 converts the coordinates of each vertex of an object defined as a polyhedron on the world coordinate system to the coordinate system seen from the viewpoint, and outputs data in the regular device coordinate system. In the regular device coordinate system, the entire visible region is mapped inside a cube whose coordinate axes x, y, and z have lengths of 1. Next, the display control device 12 performs hidden surface processing on a plane (polygon) made up of vertices having these converted coordinate values, and then outputs brightness information to the display device 15. As a method for constructing this display control device, the Watkins method has been known for some time.

“A Real-Time Visible Surface Algorithm” University of Utah, Department of Computer Science.

U T E C-C5c-70-101, 1970 θ
Also shown on the moon, Fujio Yamaguchi.

It is explained in detail in "Graphic Processing Engineering Using Computer Displays" 1 Nikkan Kogyosha, 1986, Section 5.7.9 (PP, 281-292). In this method, the processing program in the display control device 12 in FIG. 6 is separated into a segment management section 13 and a hidden surface processing section 14. The hidden surface processing section 14 performs hidden surface processing based on the depth data Z in units of one scan line corresponding to the rask scan of the display device 15, and the segment management section 13 performs hidden surface processing based on the depth data Z every time the scan line changes. The starting point and ending point on each scan line are calculated and output to the hidden surface processing unit 14. Figure 8 (e) shows this situation, and Figure (a) shows the X-axis and Y-axis of the normal device coordinates being output to the display device 16. horizontal axis.

Each corresponds to the vertical axis, and the horizontal and vertical resolution is L×N.
This represents the relationship between the polygon 20 existing in that space and the scan line approaching Y=7.

FIG. 6 is a view of this normal device coordinate system viewed from the front, and FIG. 6C is a cross-sectional view of Y=7. The hidden surface processing unit 14 in FIG. 5 performs hidden surface processing by focusing on the coordinates of both end points of the segment 21 (the intersection line of the polygon 20 and the scan line surface) in FIG. 6C, particularly the depth data z, , Zr.

In FIG. 6, the segment management unit 13 in FIG.
The coordinates of both end points are output to the hidden surface processing section 14 in FIG.

The segment management unit 13 takes advantage of the fact that the edge line of the polygon 2o is always a straight line, and employs a processing flow as shown in FIG. 7. Information regarding polygons (active polygons) that intersect with the current scan line surface is stored in the main memory in a list structure and managed.

When a new scan line becomes available, this list will be updated if a certain edge newly invades (becomes active)2.
If there is a ridgeline to be created, added, or removed, the burnt b list is updated and removed.

After that, hidden surface processing is performed on all active polygons, and for the next scan line, X=X+dX/dY and Z=Z+dZ/dY are calculated for all K edges. Once dX/dY and dZ/dY are calculated in advance, the calculations can be made incrementally each time the scan line changes, so the program can be executed at high speed.

Problems to be Solved by the Invention However, with the above configuration, there is a problem in that there is a limit to speedup because the active polygon table having a list structure on the main memory is managed by one concurrent processing processor. It had

In view of this, the present invention provides an input/output conversion segment memory capable of performing segment management at high speed, and a hidden surface processing device using the input/output conversion segment memory to speed up the display control device. With the goal.

Means for Solving the Problems The present invention includes a row write address counter that increments by 1 starting from Y using a segment input clock, a row decoder that decodes the row address, and a column that stores the number of data stored in each row of the memory cell array. a group of N column write address registers held as addresses;
An incrementer that increments the column address in the selected column write address register by 1, a column decoder that decodes the column address, an MXN memory cell array that stores segment data for one screen, and a segment output clock that increments the column address from 0 to 1. A column read address counter that increments by 1, a row read address counter that increments by 1 from 0 by carry output, and one row of segment data from the memory cell array is input, and the segment data specified by the column address is serially processed. This is an input/output conversion segment memory equipped with a group of M data registers for output.

Another invention is a dual port memory that inputs segment data sequentially stored in the column direction in units of polygons from a random port and outputs segment data in the row direction sequentially in units of scan lines from a serial port, and a segment manual clock. A row write address counter that increments by 1 starting from y, a write address memory that holds the number of data stored in each row of the dual port memory as a column address, and a column address in the selected column write address memory that increments by 1. This is an input/output conversion memory equipped with an incrementer that increments by 1, and a row read Atobis counter that increments the row read address by 1 as the scan line is updated.

Another invention provides a segment converter that inputs each vertex data of a polygon, converts it into segments cut by each scan line plane, and sequentially outputs the minimum value Y in the Y direction of the polygon and a plurality of segment data; An input/output conversion segment memory that serially inputs and stores segment data in the column direction from the first row address Y in units of polygons, and serially outputs segment data in the row direction in units of scan lines; A hidden surface processing device that sequentially inputs segment data, performs hidden surface processing and shading within one scan line, and outputs pixel data subjected to hidden surface processing for each scan line.

Operation: With the above-described configuration, the input/output conversion segment memory of the present invention outputs and updates the write address using the row write address counter, and outputs and updates the column write address of the row using the column write address register and incrementer. Then, segment data is sequentially written in polygon units to designated memory cells in the memory cell array. On the other hand, the row read address counter outputs and updates the row read address, one row of segment data is stored from the memory cell array in the data register, the column read address counter outputs and updates the column address, and the data register stores one row of segment data from the memory cell array. It sequentially outputs segment data in units of scan lines.

In addition, the input/output conversion segment memory of another invention has the above-described configuration, and the row write address counter outputs and updates the row write address, and the column address write memory and incrementer output and update the column write address of the row. and write segment data in polygon units sequentially from the random port of the dual port memory. - On the other hand, a row read address counter outputs and updates a row read address, and segment data in scan line units is sequentially output from a serial port of a dual port memory.

Furthermore, the hidden surface processing device of another invention has the above-described configuration, converts the segment data into segments, serially inputs the segment data in units of polygons in the input/output conversion segment memory, serially outputs the segment data in units of scan lines, and outputs the segment data serially in units of scan lines using the hidden surface processor. It performs unit hidden surface processing and shading, and sequentially outputs pixel data resulting from the hidden surface processing.

Embodiment FIG. 1 shows a block diagram of an input/output conversion segment memory in this embodiment. In Figure 1, 3o
3 is a row write address counter that stores the minimum value Y in the Y direction of the polygon and increments by 1 in response to the segment input clock 5CKI; 31 is a row address selector; 32 is a row decoder that decodes the row address;
3 is a group of N column write address registers that hold the number of data stored in each row of the memory cell array 38 as a column address; 34 is a column address buffer; 3
5 is a column address incrementer, 36 is a column address selector, 37 is a column decoder that decodes the column address, and 38 is M×N that stores seven segment data for one screen.
39 is a buffer for write data; 40 is a column read address counter that updates the column read address by the segment output clock SCK○;
41 is a row read address counter that updates the row read address; 42 is a group of M data registers that stores segment data for one scan line; and 43 is a read data buffer.

The operation of the input/output conversion segment memory of this embodiment configured as described above will be described below with reference to the three-dimensional graphics explanatory diagram shown in FIG. 6 and the input/output explanatory diagram of the memory cell array shown in FIG. I will explain.

First, writing of segment data will be explained. 1
Before inputting segment data for a screen, the column write address register 33 is initialized to 0 and the memory array 38 is initialized to dummy segment data. Then, the segment booter Il[is input to the i-th memory cell array 38 in units of polygons.

For simplicity, FIG. 4 shows the size of the memory cell array 38 as 1.
Column write address register 33 when set to 6X16
The contents and the states of the memory cell array 38 and data register 42 are shown as examples. Polygon 2 shown in Figure 6(b)
Consider the case where the segments 21 generated by incrementing o by 1 in the Y direction from Y=Y are sequentially written.

The minimum value Yyo=3 of the polygon in the Y direction is stored in the row write address counter 30. YY is output as a row address from the row write address counter 30 and inputted to the memory cell array 38 and column write address register 33 via the row decoder 32. Six segment data have already been stored in the row of the memory cell array 38 with row address = 3, and the selected column write address register 33 has stored the value 5 of the column address to be stored next. . The column address output from the column write address register 33 is input to the memory cell array 38 via the column decoder 37.

The column address stored in the selected column write address register 33 is incremented by the incrementer 35, and the value of the column address in the column write address register 33 is updated to six. Thus the row decoder 32
The first segment data of Y=Y is written via the buffer 43 into the selected memory cell of the memory cell array 38 with the row address=39 and the column address=5. Then, the value of the row address in the row write address counter 30 is also incremented by the segment manual clock 5CKI input together with the segment data, updated to 4, and output. Column write address register 3 selected with updated row address
The column address value 4 is output from 3, and the second segment data of Y=Yyo+1 is written into the memory cell of row address=49 and column address=4 in the memory cell array 3. In this way, the segment data for Y=YY is written, and the writing of segment data for one polygon is completed.

Next, reading of segment data will be explained. Before outputting segment data for one screen, the column read address counter 4o and the row read address counter 41
are both initialized and set to row 0 and column 0. Now, let us consider a case where segment data for two scan lines is outputted and the value of the row address in the row read address register 41 becomes 2, as shown in FIG. When the row read address counter 41 is incremented and the row address value becomes 2, the segment data of the third row of the selected memory cell array 38 is outputted to the data register group 42 via the row decoder 32. Then, column read address counter 4 is activated by segment output clock 5CKO.
0 is incremented, and segment data A, B, and C are sequentially output from the data register 42 via the buffer 43. The column read address counter 4° is
When a pre-stored column address value is reached or when dummy segment data is detected to be output from the data register group 42, a carry signal is output to the row read address counter 41 and the row address is updated. will be carried out. In this way, segment data is read out via the data register group 42 one scan line at a time.

As described above, according to this embodiment, by using regular elements such as column write address registers, memory cell arrays, and data registers, it is not only suitable for LSI implementation, but also allows for segment input in polygon units and segment output in scan line units. Since this is done through memory, segment management can be done very quickly.

FIG. 2 shows a block diagram of an input/output conversion memory in another embodiment of the invention. In FIG. 2, 30 is a row write address counter, 34 is a buffer, 36 is an incrementer, and 41 is a row read address counter, which are the same as in FIG. Column write address memory holds the number of stored data as a column address in each row; 46, 46, and 47 are selectors for selecting the row address, column address, write address, and read address; 48 is a polygon unit from a random port. It is a dual port memory that inputs segment data and outputs segment data in units of scan lines from the serial port.

The operation of the input/output conversion segment memory of this embodiment configured as described above will be explained below.

First, writing of segment data will be explained. 1
Before inputting segment data for a screen, the column write address memory 44 is initialized to 0 and the dual port memory 48 is initialized with dummy segment data. Then, the minimum value Y in the Y direction of the polygon is stored in the row write address counter 30. The column write address corresponding to the stored row address Y is output from the column write address memory 44, updated by the incrementer 35, and stored again at the same address in the column write address memory 44. The row and column addresses respectively output from the row write address counter 3o and column write address memory 44 are input as addresses to the dual port memory 48 via selectors 46 and 47, and Y:Ym is input to the designated address.

segment data is stored through random ports. At this time, the segment manual clock 5CKI is input to the row write address counter together with the segment data, and the row address is updated. Similarly, the next segment data is also written to the dual port memory 48 via the random port. In this manner, segment data is written to the dual port memory 48 in units of polygons.

Next, reading of segment data will be explained. The row read address counter 41 is initialized to 0 before outputting segment data for one screen. When the row read address is input to the dual port memory 48 via the selectors 46 and 47, segment data for one row is sequentially read out via the serial port in synchronization with the segment output clock 5CKO. When one row of segment data is read, the row read address counter 4
1 is incremented and the process moves to the next scan line.

As described above, according to this embodiment, not only can it be easily realized by using a general-purpose dual hold memory and a column write address memory t, but also segment input in polygon units and segment output in scan line units can be performed via memory. This allows segment management to be performed very quickly.

FIG. 3 is a block diagram of a hidden surface processing device in another embodiment of the invention. In FIG. 3, 1 is a segment converter that inputs polygons, converts them into segments, and outputs them; 2
3 is an input/output conversion segment memory that outputs input segment data in units of polygons in units of scan lines;
4 is a hidden surface processor that performs hidden surface processing and shading on a scan line basis and outputs pixel data; 4 is a CR
It is T.

The operation of the hidden surface processing device configured as described above will be described below.

First, data on each vertex of a polygon is input to the segment converter 1, and converted into segments cut by the minimum value YM of the polygon in the Y direction and each scan line plane. When the segment data converted to Yv is sequentially input to the input/output conversion segment memory 2, the row address is internally incremented by 1 from Yyo and the segment data in units of polygons is stored. In this way, one screen's worth of polygon data is converted into segments by the segment converter 1, and then held as segment data in the input/output conversion segment memory.

Next, fc is stored in the input/output conversion segment memory 2,
Segment data for one screen is sequentially output in units of scan lines and input to the hidden surface processor 3. The hidden surface processor 3 performs hidden surface processing and shading within one scan line, and after inputting all the segment data within one scan line, sequentially outputs the pixel data resulting from the hidden surface processing to the CRT 4. I/O conversion segment memory 2
The amount of segment data in one scan line that is input to the hidden surface processor 3 is always constant, and while the hidden surface processor 3 is outputting pixel data for one scan line, Since segment data can be input to the hidden surface processor 3, pixel data is continuously input to the CRT 4 and a three-dimensional image is displayed.

As described above, according to this embodiment, a segment converter that processes polygons and a hidden surface processor that processes scan lines are connected via the input/output conversion segment memory. , pipeline processing becomes possible, hidden surface processing for each polygon can be performed at high speed, and three-dimensional images can be displayed on a CRT with a simple configuration without frame memory.

In this embodiment, there is one input/output conversion segment memory, but it may be divided into two to form a double buffer configuration. Additionally, a frame memory may be provided to store three-dimensional image data.

As described in detail, according to the present invention of the input/output conversion segment memory, segment input in polygon units and segment output in scan line units are performed using address management and memory, making segment management extremely easy. It can be performed easily and at very high speed, and its practical effects are great.

Furthermore, as explained above, according to the present invention of the hidden surface processing device, the segment converter that processes each polygon and the hidden surface processor that processes each scan line are connected via the input/output conversion segment memory. This not only facilitates temporary storage of three-dimensional data, but also allows very high-speed hidden surface processing in units of polygons, which allows pipeline processing, and has great practical effects.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an input/output conversion segment memory according to an embodiment of the first invention, FIG. 2 is a block diagram of an input/output conversion segment memory of an embodiment of the second invention, and FIG. 3 is a block diagram of an input/output conversion segment memory of an embodiment of the second invention. FIG. 4 is an explanatory diagram of the operation of the first invention; FIG. 6 is a block diagram of a conventional three-dimensional graphic device;
FIG. 6 is an explanatory diagram of the basic concept of the three-dimensional graphic device, and FIG. 7 is a processing flow diagram of a conventional segment management unit. 30...Line write address counter, 32...
... Ite decoder, 33 ... Column write address register group, 35 , . . . , Incrementer,
37... Column decoder, 38... Memory cell array, 4o... Column read address counter, 41. . . . line read address counter, 4
2... Data register group, 44... Column write address memory, 48 Old... Dual baud 1
Memory, 1... Segment converter, 2...
... Input/output conversion segment memory, 3... Hidden surface processor. Name of agent: Patent attorney Shigetaka Awano and 1 other person

Claims (4)

[Claims] (1) A row write address counter that stores the minimum or maximum value of a polygon in the Y direction and increments by 1 from the minimum or maximum value using a segment input clock, and a row address that is output from the row write address counter. A row decoder to be decoded and N column write functions that hold the number of data stored in each row of a memory cell array (described later) as a column address, and output the column address to be written next in the row selected by the row decoder. an incrementer for incrementing the contents of the selected column write address register by 1 and storing it again;
A column decoder that decodes a column address output from the column write address register, and an Mx that stores segment data for one screen by writing segment data into memory cells selected by the row decoder and the column decoder. N memory cell arrays, a column read address counter that increments by 1 from 0 based on a segment output clock, a row read address counter that increments by 1 from 0 based on the carry output of the column read counter, and a column read address counter that increments by 1 from 0 based on the carry output of the column read counter. M data registers that store segment data for one row of the selected memory cell array each time the column read address counter is incremented by one, and output segment data of the selected column each time the column read address counter is incremented by one. An input/output conversion segment memory characterized by comprising a group. (2) A dual port memory that inputs segment data sequentially stored in the column direction in units of polygons from a random port and outputs segment data in the row direction sequentially in units of scan lines from the serial port, and the minimum value of polygons in the Y direction Alternatively, a row write address counter that stores a maximum value and increments by 1 from the minimum value or maximum value by a segment input clock, and holds the number of data stored in each row of the dual port memory as a column address; A column write address memory that outputs the column address to be written next in the row selected by the row address output from the row write address counter, and the contents of the selected column write address memory are incremented by 1 and stored again. and a row read address counter that increments a row read address by 1 every time segment data for one scan line is read from the dual port memory. (3) Each vertex data of polygons constituting a three-dimensional object (
Input the X coordinate value Segment data (X coordinate value of the left end point
, the length in the X direction ΔX, the Z coordinate value Z_e of the left end point, the inclination ΔZ/ΔX of the Z coordinate, and the brightness I_e), and segment data sequentially output in polygon units from the segment converter. An input/output conversion segment memory that serially inputs data in the column direction from the first row address, stores the segment data, and serially outputs the segment data in the row direction in scan line units; Input the segment data that is output sequentially in
A hidden surface processing device comprising: a hidden surface processor that performs hidden surface processing and shading within one scan line and outputs pixel data (luminance I_p) subjected to hidden surface processing for each scan line. (4) Each vertex data of polygons constituting a three-dimensional object (
Input the X coordinate value Segment data (X coordinate value of the left end point
, length in the X direction ΔX, Z coordinate value Z_e of the left end point, slope of the Z coordinate ΔZ/ΔX, brightness I_e of the left end point, slope of brightness Δ
A segment converter that sequentially outputs I / Δ An input/output conversion segment memory that serially outputs segment data in the row direction and segment data sequentially output in scan line units from the input/output conversion segment memory are input, and hidden surface processing and shading within one scan line is performed. , and a hidden surface processor that outputs pixel data (luminance I_p) subjected to hidden surface processing for each scan line.