JP2001056677A - Device and method for graphics processing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the difference between the color to be displayed and an original color while superimposing and displaying semitransparent graphics. SOLUTION: In a graphics processing device which superimposes and displays three pictures Z1, Z2 and Z3, for example, a pseudo-color corresponding to the color of the picture Z1 located in the last surface is stored in a specific picture buffer. The pseudo-color stored in the specific picture buffer represents a typical color of plural colors made into a group, and the color is previously registered in a table. The device has one more picture buffer besides the specific picture buffer mentioned above and the picture Z3 which is located in front of the picture Z2 is stored in the buffer. When a semitransparent processing is conducted for the pictures stored in the two picture buffers, the displayed color at a point P is αcolor-Z3+(1-α)color-T, (color-Z3 is the color of the picture Z3 and color-T is the pseudo-color corresponding to the color of the picture Z1) and a picture reflecting the color of the picture Z1 located in the last surface is displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphics processing apparatus, a graphics processing method, and a recording medium on which a program for the method is recorded.

[0002]

2. Description of the Related Art Graphics processing by a general-purpose computer or a dedicated graphics engine, in particular, processing of superimposing a plurality of images by translucent processing, is performed after a system reset and setting / defining various places, and a synchronization signal is generated. It can be executed by sequentially performing an initialization process, a storage process, and a display process.

FIG. 11 is a flowchart showing an initialization process in a graphics process according to a conventional example. In this initialization process, first, “0” is substituted as an initial value into a temporary variable tmp for counting the number of processing surfaces and a temporary variable dotcount for counting the number of processing dots (step ST61). Next, whether the size of the screen × axis direction Display_END is equal to or larger than the temporary variable dotcount for counting the number of processed dots, that is, whether the pixel address of the image buffer currently being processed does not exceed the last pixel address It is determined whether or not (step ST62).

When it is determined that the size of the screen × axial direction Display_END is equal to or greater than the temporary variable dotcount for counting the number of processing dots, it is determined whether the maximum number of superimposed surfaces max_men is equal to or greater than the current number of processing surfaces tmp. It is determined whether or not it is (step ST63).

If it is determined that the maximum number of superimposed faces max_men is equal to or greater than the current number of processing faces tmp, the palette address
palette [temp] [dotcount], priority value yusen [temp] [dot
count] and translucent value [temp] [dotcount] are set to values empty indicating that nothing is contained in the image buffer (step ST64). Further, the current processing surface number tmp is added by "1" (step ST65). Then, the process returns to step ST63.

On the other hand, when it is determined that the maximum number of superimposed surfaces max_men is smaller than the current number of processed surfaces tmp, a temporary variable dotcount for counting the number of processed dots is added by "1" and the current processed surface number is incremented. The value of the number tmp is initialized to "0" again (step ST66). Then, step ST62
Return to the processing of.

If it is determined in step ST62 that the size of the screen × axis direction Display_END is not larger than the temporary variable dotcount for counting the number of dots to be processed, the image buffer is emptied. After that, the initialization processing ends, and the flow advances to the next graphics processing.

FIG. 12 is a flowchart showing storage processing in graphics processing according to a conventional example. In this storage processing, first, it is determined whether or not there is a pixel in the image buffer to store the image (step ST7).
1). There are cases where there are a plurality of pixels in which an image is to be stored.
It is determined whether or not there remains any one of which has not been subjected to the processing of 72 to ST76. If there is no pixel to store the image, the storage process ends, and the process proceeds to the display process.

When there is a pixel to store an image, "0" is substituted as an initial value into a variable "temp" indicating the number of processing surfaces, so that the image buffer is set to the foreground and the display priority value is indicated. Display priority value i input to variable tmp_yusen
np_yusen, translucent value inp_yusen input to variable tmp_half indicating translucent value, variable tm indicating palette address value
palette address value input to p_palette inp_palette
Are respectively assigned (step ST72).

Next, it is determined whether or not the variable tmp indicating the current number of processing surfaces exceeds the maximum number of surfaces max_men (step ST73). If it is determined that the variable tmp indicating the current number of processing planes does not exceed the maximum number of planes max_men, the temporary variable tmp_yusen indicating the display priority is stored in the image buffer and the display priority value yusen [tmp] It is determined whether it is larger than [inp_add], that is, whether the temporary priority is higher (step ST74).

Temporary variable tmp_yuse indicating display priority
display priority value yusen where n is stored in the image buffer
If it is determined that the value is not larger than [tmp] [inp_add], the value of the temporary variable tmp indicating the current number of processing surfaces is added by “1” (step ST75), and the process returns to step ST73.

Temporary variable tmp_yuse indicating display priority
display priority value yusen where n is stored in the image buffer
If it is determined that it is larger than [tmp] [inp_add], the image data is stored in the image buffer. That is, the variable
The value of yusen [tmp] [inp_add] is set to the variable yusen, and the variable half [tm
p] [inp_add] value to variable half, variable palette [tmp] [inp_
add] value to variable palette, and variable tmp_yusen value to variable yu
In sen [tmp] [inp_add], add the value of variable temp_half to variable half [t
mp] [inp_add] and the value of the variable tmp_palette into the variable palette [t
mp] [inp_add], the value of variable yusen to variable tmp_yusen, the value of variable half to variable tmp_half, and the value of variable palette to variable t
Assign to mp_palette respectively. Further, the value of the variable tmp indicating the current number of processing surfaces is added by "1" (step ST76). Then, the process returns to step ST73.

On the other hand, if it is determined in step ST73 that the variable tmp indicating the current number of processing surfaces exceeds the maximum surface number max_men, the process returns to step ST71. If there are no more pixels to store the image, step ST
The determination result at 71 is No, the storage process ends,
The process will proceed to the display process.

According to the storage processing described above, the images are sequentially stored in the image buffer in order from the front image. However, images on the back side that exceed the number of image buffers are not stored in the image buffer in this conventional graphics processing.

FIG. 13 is a flowchart showing a display process in a graphics process according to a conventional example. In this display processing, first, “0” is substituted for a variable dotcount for counting the number of dots to be processed (step ST81).
Next, the value of the variable dotcount indicates the size of the screen × axis direction
It is determined whether the value is smaller than the value of Display_END (step ST82).

When it is determined that the value of the variable dotcount is smaller than the value of Display_END indicating the size in the screen × axial direction, the value of the maximum number of faces max_men is substituted for the variable tmp indicating the current number of processing faces, and the output is performed. The data of the transparent color (color [0]) is substituted for the color value outcolor to be performed (step ST83).

Next, the translucent process is performed by performing the operation of Expression 1, and the value of the variable tmp indicating the current number of processed surfaces is subtracted by "1" (step ST84).

[Equation 1] outcolor = half [tmp] [dotcount] * color [pal
ette [tmp] [dotcount]] + (1-half [tmp] [dotcount]) *
outcolor

Next, it is determined whether or not the value of the variable tmp representing the current number of processing surfaces is larger than "0" (step S).
T85). If it is determined to be larger, step ST84
Return to the processing of. On the other hand, when it is determined that it is not large, the color data indicated by outcolor is output for the current dot of the display device 3 indicated by the variable dotcount, and
The value of dotcount is added by “1” (step ST8)
6). Then, the process returns to step ST82.

Then, in step ST82, the variable dotcount
Is determined to be not smaller than the value of Display_END indicating the size in the screen × axis direction, the display process ends. By this display processing, the image stored in the image buffer in the above storage processing is translucently processed and superimposed,
An image to be displayed on the display device is generated.

A graphics engine for realizing the above-described conventional graphics processing as dedicated hardware can be realized, for example, as shown in FIG. This graphics engine has three image buffers B11 to B13. The control unit B4 controls each unit in the graphics engine in response to a request from the CPU B1 that performs other processing linked with the graphics processing. The graphics engine unit B3 includes a control unit B
4 according to the control signal from the image buffers B11 to B1.
3 to output image data to be stored. The α blending computing unit B21 computes color data and supplies the computed color data to an external display device B22.

When performing graphics processing with this graphics engine, first, a system reset signal S2
Is activated, and the control unit B4 is reset. next,
The CPU_I / F signal S1 is sent from the CPU B1 to the control unit B4.
Is output to the control unit B4 and the graphics engine unit B3. Further, the display unit B is transmitted from the control unit B4.
The initialization process is started by outputting the synchronization signal S12 to the counter 22.

In the initialization process, the control unit B4
The initialization signal S40 is activated to output an empty signal from the demultiplexers B8 and B9 and the selector B10. The graphics engine unit B3 stores the stored image WEB in accordance with the control signal S6 from the control unit B4.
S10 is activated, and the storage image address S9 is sequentially incremented, so that all palette [i] [j], yusen [i] [j], and palette [i] [j] prepared in the image buffers B11 to B13.
Set empty to half [i] [j]. When the initialization processing ends in this way, the storage processing starts.

In the storing process, the control unit B4 operates the CPU B
According to the CPU_I / F signal S1 output from the CPU 1, an engine control signal S6 is output to the graphics engine unit B3 as a parameter required for a figure to be displayed. The graphics engine unit B3 calculates the ROM address S3 from the parameter given by the engine control signal S6, and outputs it to the character ROM B2. Character R
OM B2 is R from graphics engine unit B3.
The ROM data S4 is returned to the graphics engine B3 according to the OM address S3.

The graphics engine section B3 stores the set value and the returned R at the start of the graphics processing.
According to the OM data S4, the image data S5 is sequentially output to the image buffers B11 to B13, and the engine output image WEB S7 and the engine output image address S8 are sequentially output to the control unit B4. Here, the image data S5 is a palette, yuse
It is data composed of three elements, n and half.

Next, the comparator B5 compares yusen included in the image data S5 with yusen included in the image buffer output signal S28 output from the image buffer B11, and performs priority switching according to the comparison result. The signal S21 is output. In accordance with the priority switching signal S21, the demultiplexer B8 outputs the higher one of the image data S5 and the image buffer output signal S28 as the image buffer input signal S29, and outputs the lower one as the next image buffer comparison data S41. Here, the image buffer B11
Stores the image buffer input signal S29.

Next, the comparator B6 calculates the difference between yusen included in the next image buffer comparison data S41 and the image buffer B12.
Is compared with yusen included in the image buffer output signal S27 output from the CPU, and a priority switching signal S22 according to the comparison result is output. Demultiplexer B9 is
In accordance with the priority switching signal S22, the higher one of the next image buffer comparison data S41 and the image buffer output signal S27 is set as the image buffer input signal S30.
The lower one is output as the next image buffer comparison data S42. Here, the image buffer B12 stores the image buffer input signal S30.

Next, the comparator B7 compares yusen included in the next image buffer comparison data S26 with the image buffer B12.
Is compared with yusen included in the image buffer output signal S31 output from the CPU, and a priority switching signal S23 according to the comparison result is output. When the next image buffer comparison data S26 has a higher priority according to the priority switching signal S23, the selector B22 outputs this as the image buffer input signal S27 and stores it in the image buffer B13. Otherwise, the image buffer output signal S
31 is stored again in the image buffer B13. The above operation is repeated for images of all pixels and all surfaces. When the storing process ends, the display process starts.

In the display processing, the control unit B4 operates to store the stored image address S9 given to the image buffers B11 to B13.
Are sequentially incremented from 0, and the image buffer B
Image data (image buffer output signals S26 to S28) is sequentially output in units of one pixel from 11 to B13. The selector B14 extracts pallet addresses S33 to S35 from the image buffer output signals S26 to S28 output from the image buffers B11 to B13, respectively.
The pallet address S32 is sequentially output to the pallet RAM B15 according to the pallet control signal S11 from the control unit B4.

The palette RAM B15 outputs color data S36 in accordance with the supplied palette address S32, and sequentially stores the color data in flip-flops B16, B18 and B20 in accordance with the palette control signal S11 from the control unit B4. Further, according to the pallet control signal S11 from the control unit B4, the translucency S37, S38, and S43 of the image buffer output signals S26 to S28 output from the image buffers B11 to B13 are transmitted to the flip-flops B17, B19, and B23. Each is accumulated sequentially. Further, the pallet control signal S11 from the control unit B4
, The transparent color data S45 set in the palette RAM B15 is sequentially stored in the flip-flop B24.

Then, the α blending operation unit B21
Are the color data stored in the flip-flops B16, B18, B20, respectively, and the flip-flops B17, B1
The translucent process is performed by sequentially performing predetermined calculations on the translucent rates stored in the pixels 9 and B23 and the transparent color data stored in the flip-flop B24, respectively. The α blending calculator B21 sequentially outputs the calculation result to the display device B22 as color data B39 of an image to be displayed. In this way, the color data B39 is output for all the addresses, and when the display processing is completed, the control unit B
4 again outputs the synchronization signal S12, and further performs an initialization process.

[0031]

When translucent figures are displayed in a superimposed manner in the above-mentioned conventional graphics processing, as described below, a large error is generated between the ideal colors. There was a problem.

FIG. 15 is a diagram for explaining colors of an image actually displayed on a display device when a translucent image is displayed in an overlapping manner in the conventional graphics processing. Here, it is assumed that three images to be superimposed and displayed are Z1, Z2, and Z3 in order from the rear side, and the translucency of the images Z2 and Z3 is β and α, respectively. The translucency β is 0
Shall be close to The rear surface image Z1 is generally non-transparent. It is also assumed that there are only two image buffers for storing these figures.

At this time, the color "color_P" of the original image at the point P shown in FIG.

[Equation 2] color_P = αcolor_Z3 + (1-α) (βcolor_Z2 +
(1-β) color_Z1) where color_Z * is the color at point P of image Z *

However, in this graphics processing apparatus, since there are only two image buffers, only the front side images Z3 and Z2 are stored in the image buffer. Then, the image Z4 actually displayed on the display device is displayed.
The color color_P "at the point P is as shown in Expression 3.

[Equation 3] color_P "= αcolor_Z3 + (1-α) βcolor_Z2

In this case, since the translucency β is close to 0, the color color_Z2 of the image Z2 does not significantly affect the color of the displayed image. Rather, the color of the displayed image is influenced by the color colo of the non-transparent last image Z1.
r_Z1. As described above, in the conventional graphics processing device, when there are more images to be superimposed and displayed than the number of image buffers, the color of the last image which has a greater effect on the color of the displayed image is considered. And there is a problem that a large error occurs between an ideal color that should be displayed originally.

The present invention has been made to solve the above-mentioned problems of the prior art, and can reduce an error from an ideal color to be displayed when a translucent figure is displayed in a superimposed manner. An object of the present invention is to provide a graphics processing apparatus, a method, and a recording medium on which a program for the method is recorded.

[0037]

In order to achieve the above object, a graphics processing apparatus according to a first aspect of the present invention converts a predetermined image from an n-plane image to be superimposed and displayed. a graphics processing device that stores the image data in m (m <n) image buffers and processes the images stored in the m image buffers to generate image data to be displayed on a display device; Initializing means for initializing m image buffers and storing the last image of the n images to be superimposed and displayed in a specific one of the m image buffers When,
Storage means for storing a predetermined image other than the last one of the n-side images to be superimposed and displayed on a part other than a specific one of the m image buffers; Display processing means for translucently processing an image stored in a specific image buffer and an image stored in an image buffer other than the specific image buffer by the storage means to generate display data for display on a display device; It is characterized by having.

In the above-described graphics processing apparatus, even if the number of images to be superimposed and displayed is larger than the total number of image buffers, the last image having a translucency of 1 is generally used as a background image. Will be stored in a specific image buffer by the initialization means. Therefore, the image displayed on the display device according to the display data generated by the display processing means always reflects the color of the image on the last surface. For this reason, even if the translucent ratio of the image in front of it is all low, the color of the image that should be displayed by superimposing all the images and the color of the image that is actually displayed Does not cause a large error between them.

The graphics processing apparatus further includes a pseudo color table storing means for storing a pseudo color table in which a predetermined number of pseudo color data and color data included in each pseudo color data are registered in association with each other. be able to. In this case, the initialization means stores data corresponding to the image of the last surface of the images of the n surfaces which are the targets of the overlay display processing in a specific one of the m image buffers, The display processing means converts the pseudo color data stored in the pseudo color table storage means corresponding to the data stored in the specific image buffer to color data corresponding to an image stored in another image buffer. The translucency processing can be performed by performing the arithmetic processing.

In this case, prior to the initialization of the image buffer by the initializing means, the graphics processing apparatus performs processing on the basis of the last image of the n images to be subjected to the overlay display processing. And a pseudo color table generating means for generating a pseudo color table and storing the pseudo color table in the pseudo color table storage means.

Here, the pseudo color table generating means includes:
For example, a predetermined number of frequently used color data in the last image among the n-images to be subjected to the overlay display process are extracted as pseudo-color data, and the last color data not extracted as pseudo-color data is extracted. A pseudo color table can be generated by associating other color data included in the image on the surface with any of the extracted pseudo color data.

By providing the pseudo color table in this manner, it is not necessary to store the color data itself of the image in the specific image buffer for storing the last image, and only the smaller amount of data can be stored. That would be good. Therefore, it is possible to reduce the capacity of the specific image buffer.

In the above-mentioned graphics processing apparatus, the image of the n-plane to be subjected to the overlay display processing includes:
Each may be given a priority. In this case, the storage means may store the image with the higher priority in a priority order other than the specific one of the m image buffers.

In the above graphics processing apparatus, the storage means sequentially processes the images other than the last one of the n-side images to be subjected to the superimposing display processing in units of pixels, and stores the pixels in units of pixels. May be sequentially stored in the m image buffers other than the specific one.

In order to achieve the above object, a graphics processing apparatus according to a second aspect of the present invention comprises a specific image buffer for storing a specific image among images to be superimposed and displayed, One or more non-specific image buffers each storing an image other than the specific image among the images to be superimposed and displayed, and the image stored in the specific image buffer and the non-specific image buffer And a control device for controlling the translucent processing of the image stored in the specific image buffer and the non-specific image buffer, and controlling the translucent processing by the arithmetic device. The apparatus initializes the specific image buffer and the non-specific image buffer, respectively, and sets the last of the images targeted for the superimposed display processing. The specific image buffer is stored in the specific image buffer, a predetermined image is selected from images other than the last surface among the images to be subjected to the overlay display processing, and stored in the non-specific image buffer. The arithmetic device performs translucent processing on the images stored in the image buffer and the non-specific image buffer, respectively. The number of non-specific image buffers is larger than the total.

The graphics processing device may further include a pseudo color table in which a predetermined number of pseudo color data and color data included in each pseudo color data are registered in association with each other. In this case, the control device stores, in the specific image buffer, data corresponding to an image on the last surface of the images to be superimposed and displayed, and the arithmetic device stores the data in the specific image buffer. The semi-transparent process can be performed by reading the pseudo-color data corresponding to the obtained data from the pseudo-color table and performing arithmetic processing on the color data corresponding to the image stored in the non-specific image buffer.

In order to achieve the above object, the graphics processing method according to the third aspect of the present invention converts a predetermined image from an n-plane image to be superimposed and displayed by m (m <n). A graphics processing method for processing the images stored in the m image buffers to generate image data for displaying on a display device, wherein the m image buffers are stored in the m image buffers. An initialization step of initializing and storing the last image of the n-side images to be subjected to the overlay display processing in a specific one of the m image buffers; Storing a predetermined image other than the last one of the images of the n-planes to be processed in the m-image buffer other than a specific one of the m-image buffers; And a display processing step of performing a translucent process on the image stored in the buffer and the image stored in the image buffer other than the specific one in the storing step to generate display data for display on a display device. Features.

The graphics processing method may further include a pseudo color table registration step of registering a predetermined number of pseudo color data and color data included in each pseudo color data in the pseudo color table in association with each other. in this case,
The initialization step stores data corresponding to the last image of the n-surface images to be subjected to the superimposition display processing in a specific one of the m image buffers. Is translucent by performing arithmetic processing on the pseudo color data registered in the pseudo color table corresponding to the data stored in the specific image buffer with the color data of the image stored in another image buffer. Processing may be performed.

To achieve the above object, a computer-readable recording medium according to a fourth aspect of the present invention comprises:
A predetermined image is stored in m (m <n) image buffers from the n-side image to be subjected to the overlay display processing,
A program for processing an image stored in the m image buffers to generate image data to be displayed on a display device, wherein the program initializes the m image buffers, An initialization step of storing the last image of the n-plane images to be subjected to the overlay display processing in a specific one of the m image buffers; Storing a predetermined image other than the last one of the n-side images in the m image buffers other than a specific one of the m image buffers, and storing the predetermined image in the specific image buffer in the initialization step A display processing step of translucently processing the image and the image stored in the image buffer other than the specific image buffer in the storage step to generate display data for display on a display device. Characterized by recording a program to be executed by the data.

The computer-readable recording medium is for causing a computer to execute a pseudo color table registration step of registering a predetermined number of pseudo color data and color data included in each pseudo color data in a pseudo color table in association with each other. May be further recorded. In this case, the initialization step stores data corresponding to the last one of the n-side images targeted for the overlay display process in a specific one of the m image buffers, The display processing step calculates the pseudo color data registered in the pseudo color table corresponding to the data stored in the specific image buffer with the color data of the image stored in another image buffer. Can perform translucent processing.

[0051]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of a general-purpose computer system applied to graphics processing according to this embodiment. As shown in the figure, this computer system has a CPU (Central Processing).
Unit) 11 and a computer 1 including a storage device 12
, An input device 2 and a display device 3.

The CPU 11 executes the graphics processing of this embodiment by a program shown in a flowchart described later. The storage device 12 stores a program to be executed by the CPU 11 and other data.
Used as a work area for the PU 11. Input device 2
Inputs data or inputs an instruction to the CPU 11. The display device 3 displays an image subjected to graphics processing by the CPU 11.

Hereinafter, graphics processing according to this embodiment will be described. In the graphics processing according to this embodiment, prior to performing the graphics processing, a pseudo color table generation processing shown in the flowchart of FIG. 2 is performed. This pseudo color table generation process
The process starts by inputting a predetermined instruction from the input device 2.

In the pseudo color table generation processing, the CPU 11
First counts the number of colors used in the last image. When counting the number of colors, for example, if the color A is used in one pixel, the count value for the color A is set to 1, and if the color A is also used in other pixels, the color A is used. The count value for the color A is incremented for each pixel (step X1).

Next, the CPU 11 extracts, as pseudo colors, colors having a high usage rate, that is, a predetermined number of colors having a larger value counted in step X1 from the larger number of counted numbers. Further, the CPU 11 assigns a unique group number to each of the extracted pseudo colors (step X2). CPU1
1 registers the predetermined number of pseudo colors extracted in step X2 in the pseudo color table in association with the color data (step X3).

Next, the CPU 11 extracts a plurality of extracted colors that are not used as pseudo colors in step X1 and are used in the image to be superimposed by the translucent process. The group number of the closest color among the pseudo colors is assigned as the group number of each color. Then, the CPU 11 registers the color data of each color in the pseudo color table in association with the pseudo color of the group (step X4). Thus, a pseudo color table is created, and the processing of this flowchart ends.

FIG. 3 is a diagram schematically showing a pseudo color table generated by the above pseudo color table generation processing. As shown in the drawing, the extracted pseudo color and color data are stored in association with each other in the pseudo color table. A bit indicating the group to which the color data belongs is provided above or below the color data.

When the pseudo color table generation processing is completed, next, the graphics processing shown in the flowchart of FIG. 4 is executed. This graphics processing is also started by inputting a predetermined instruction from the input device 2 in a state where the pseudo color table generation processing has already been completed.

In the graphics processing, the CPU 11
First, a system reset and setting or definition of each value are performed. Here, the size of screen x axis direction is Display_END
The maximum number of sheets to be superimposed is max_men, the temporary variable for counting the number of processing surfaces is tmp, the temporary variable for counting the number of processing dots is dotcountn, and the palette address stored in the image buffer is palette [ i] [j] is the display priority value stored in the image buffer, yusen [i] [j]
The half-transparency value stored in the image buffer to half [i]
Store the pseudo color group number value stored in the pseudo color table in c_group [j], the image buffer address value of the image to be stored in inp_add, and the palette address value of the image to be stored in inp_palette at [j]. The display priority value of the image is inp_yusen, and the translucent value of the stored image is inp_half
In the temporary variable tmp_pal that stores the palette address value
The temporary variables that store the display priority value in ette and palette, tmp_yusen and yusen, the temporary variables that store translucent values in tmp_half and half, the output color values in outcolor, and the number of pseudo color tables i and j are set to dummy as arbitrary values (step ST1).

Next, the CPU 11 waits for the input of a synchronizing signal (step ST2). When there is an input of the synchronizing signal, the CPU 11 performs an initialization process described later (step ST3).
A storage process described later is performed (step ST4), and a display process is further performed (step ST5). When the display process is completed, the process returns to step ST2 to wait for the input of the synchronization signal, and the image is displayed on the display device 3 by repeating the above process.

Hereinafter, "initialization processing (step ST3)" and "storage processing (step ST3)" in FIG.
4) ”and“ display processing (step ST5) ”will be described in detail.

FIG. 5 is a flowchart showing the details of the initialization process in step ST3. In the initialization processing, the CPU 11 first substitutes “0” as initial values for a temporary variable tmp for counting the number of processing surfaces and a temporary variable dotcount for counting the number of processing dots (step ST31). . Next, the CPU 11
Determines whether the size of screen x axis direction Display_END is greater than or equal to the temporary variable dotcount for counting the number of processed dots, that is, whether the pixel address of the image buffer currently being processed does not exceed the last pixel address (Step ST32).

When it is determined that the size of the screen × axial direction Display_END is equal to or larger than the temporary variable dotcount for counting the number of dots to be processed, the CPU 11 subtracts “1” from the maximum surface number max_men to be superimposed. Is greater than or equal to the current processing surface number tmp (step ST33).

If it is determined that the maximum number of superimposed faces max_men is equal to or greater than the current number of processed faces tmp, the CPU 11
alette address palette [tmp] [dotcount], priority value yu
sen [tmp] [dotcount], translucent value [tmp] [dotcount] A value indicating that there is nothing in the image buffer.
Set. Further, the current processing surface number tmp is added by "1" (step ST34). Then, the process returns to step S33.

On the other hand, if it is determined that the maximum number of superimposed surfaces max_men is smaller than the current number of processed surfaces tmp,
11 is in the pseudo color table number value c_group [dotcount]
Substitute the value of p_palette. Further, the CPU 11 sets the temporary variable dotcount for counting the number of processed dots to “1”.
And the value of the current processing surface number tmp is initialized to “0” again (step ST35). Then, step S3
It returns to the process of 2.

If it is determined in step ST32 that the size in the screen × axis direction Display_END is not larger than the temporary variable dotcount for counting the number of dots to be processed, the CPU 11 terminates the initialization processing. Then, the process returns to the main routine (FIG. 3).

FIG. 6 is a flowchart showing the details of the storing process in step ST4. In the storing process, the CPU 1
1 judges whether or not there is a pixel for storing an image in the image buffer (step ST41). There are cases where there are a plurality of pixels to store an image.
Is a step ST42 to be described later among such pixels.
It is determined whether or not there remains any of which has not been subjected to the processing of steps ST48 to ST48. This storage request includes the image buffer address value inp_add of the image to be stored, the display priority value inp_yusen of the image to be stored, and the translucent value inp_half of the image to be stored.
Is performed by inputting the palette address value inp_palette of the image to be stored. If there is no pixel to store the image, the storing process ends, and the process returns to the main routine (FIG. 3).

Next, the CPU 11 substitutes “0” as the initial value for the number of processing planes to set the image buffer to the foreground, and sets the display priority value input to the variable tmp_yusen indicating the display priority value. inp_yusen, translucent value inp_yusen input to variable tmp_half indicating translucent value, palette
Palette input to the variable tmp_palette indicating the address value
The address value inp_palette is substituted for each (step ST42).

Next, the CPU 11 determines whether or not the variable tmp indicating the current number of processing surfaces exceeds a value obtained by subtracting “1” from the maximum surface number max_men (step ST43).
If it is determined that the variable tmp indicating the current number of processing surfaces exceeds the maximum number of surfaces max_men, the process returns to step S41.

On the other hand, when it is determined that the variable tmp indicating the current number of processing planes does not exceed the value obtained by subtracting “1” from the maximum number of planes max_men, the CPU 11 sets the temporary display indicating the display priority order. Variable tmp_yusen is stored in the image buffer. Display priority value yusen [tmp] [inp_add]
It is determined whether or not the priority is higher, that is, whether the temporary priority is higher (step ST44).

Temporary variable tmp_yuse indicating display priority
display priority value yusen where n is stored in the image buffer
If it is determined that it is not larger than [tmp] [inp_add], C
The PU 11 adds the value of the temporary variable tmp indicating the current number of processing surfaces by “1” (step ST45), and returns to the process of step ST43.

Temporary variable tmp_yuse indicating display priority
display priority value yusen where n is stored in the image buffer
If it is determined that it is larger than [tmp] [inp_add], the CPU
No. 11 exchanges the data stored in the image buffer (step S46). That is, the variable yusen [tm
p] [inp_add] value to variable yusen, variable half [tmp] [inp_ad
d] to variable half, palette [tmp] [inp_add] to palette, and tmp_yusen to yusen [tmp]
In [inp_add], add the value of variable tmp_half to variable half [tmp] [inp_a
dd] and the value of the variable tmp_palette into the variable palette [tmp] [inp_a
dd], the value of the variable yusen to the variable tmp_yusen, the value of the variable half to the variable tmp_half, and the value of the variable palette to the variable tmp_palet
Assign to te respectively. Further, the value of the variable tmp indicating the current number of processing surfaces is added by “1”, and the process proceeds to step ST43.
Return to the processing of.

FIG. 7 is a flowchart showing the display processing of step ST5 in detail. In the display processing, the CPU 1
1 is a variable dotcount for counting the number of processed dots.
Is substituted for "0" (step ST51). Next, CP
U11 determines whether or not the value of the variable dotcount is smaller than the value of Display_END indicating the size in the screen × axial direction (step ST52).

If it is determined that the value of the variable dotcount is smaller than the value of Display_END indicating the size in the screen × axis direction, the CPU 11 substitutes the value of the maximum number of surfaces max_men into the variable tmp indicating the current number of processing surfaces. And output color value outcolor
Is substituted for the value of dummy_color [c_group [dotcont]] (step ST53).

Next, the CPU 11 performs the operation of Equation 4 to perform the translucent processing, and a variable indicating the current number of processing surfaces.
The value of tmp is subtracted by "1" (step ST54).

[Equation 4] outcolor = half [tmp] [dotcount] * color [pal
ette [tmp] [dotcount]] + (1-half [tmp] [dotcount]) *
outcolor

Next, the CPU 11 determines whether or not the value of the variable tmp representing the current number of processing surfaces is larger than "0" (step ST55). If it is determined to be larger, the process returns to step ST54. On the other hand, if it is determined that it is not large, the current display device 3 indicated by the variable dotcount
The color data indicated by outcolor is output for the dot of, and the value of the variable dotcount is added by "1" (step ST56). Then, the process returns to step ST52.

Then, in step ST52, the variable dotcount
Is determined to be not smaller than the value of Display_END indicating the size in the screen × axis direction, the process of this flowchart is terminated, and the process returns to the main routine (FIG. 3).

The graphics processing according to this embodiment, in particular, the processing of a translucent image, which is performed according to the above flowchart, will be described with reference to FIG. Here, it is assumed that only one image buffer is prepared for storing an image other than the last image Z1. The images to be processed are three images Z1, Z2, and Z3 from the rear side, and the translucency of each is 1, β, and α (β ≒ 0.5). A point at which three of the images Z1, Z2, and Z3 should be superimposed is referred to as a point P.

In this example, three images Z1, Z2,
When translucent processing is performed by superimposing all Z3s,
Color co at point P of the image that should be displayed on the display device
lor_P is represented by the following Expression 5.

[Equation 5] color_P = αcolor_Z3 + (1-α) (βcolor_Z2 +
(1-β) color_Z1) where color_Z * represents the color at point P of image Z *.

However, there is only one image buffer for storing images Z2 and Z3 other than the last image Z1.
Therefore, the foreground image Z3 is stored in this image buffer. In the last image Z1, a pseudo color group number corresponding to the color of the image is stored in the image buffer.

When the pseudo color corresponding to the color of the image Z1 stored in the two image buffers and the image Z3 are superimposed to perform the translucent processing, the P of the image Z5 actually displayed on the display device is displayed. The color color_P ′ at the point is represented by the following Expression 6.

[Mathematical formula-see original document] color_P '= αcolor_Z3 + (1-α) color_T where color_T is a pseudo color corresponding to the color of the image Z1.

As described above, the image at the point P actually displayed on the display device has a high translucency, and the color of the image on the rearmost surface, which greatly affects the color of the displayed image, is reflected by the pseudo color. It was done.

As described above, in the graphics processing according to this embodiment, even if the number of images to be subjected to the superposition display processing is larger than the total number of image buffers, it is generally translucent. The last image having the rate of 1 is stored in a specific image buffer during the initialization processing. Therefore, the image displayed on the display device according to the display data generated in the display processing is
This means that the color of the last image is always reflected. For this reason, a large error does not occur between the color of the image that should be originally displayed by superimposing all the images and the color of the image that is actually displayed.

Further, a pseudo color table is generated by the pseudo color table generation process, and the pseudo color group data is stored in a specific image buffer at the time of initialization, so that the image buffer has a smaller number of bits than the color data. Only the group data needs to be stored. This makes it possible to reduce the capacity of the image buffer for storing the last image.

The graphics processing according to this embodiment can be executed using dedicated hardware (graphics engine). FIG. 9 is a block diagram showing a configuration of a graphics engine for realizing graphic processing according to this embodiment.

As shown, the graphics engine has three image buffers B11 to B13.
The image buffer B13 is an image buffer that stores a group number corresponding to the last image. On the other hand, the image buffers B11 and B12 are image buffers for storing image data of images other than the last surface. The control unit B4 is a CPU that performs other processing linked with the graphics processing.
1 controls each part in the graphics engine. The pseudo color table section B24 has a CPU
A pseudo color table created in advance by B1 is stored.

The graphics engine unit B3 controls the image buffers B11-B in accordance with the control signal from the control unit B4.
13, image data to be stored in the character ROM B2
, The engine output image WEB, and the output image address. Comparators B5 and B6 are respectively yu
The value of sen is compared, and a priority switching signal is output based on the result.

The alpha blending computing unit B21 performs a predetermined operation on the color data and the translucency output from the flip-flops (F / F) B16 to B19 and the pseudo-color color data output from the pseudo-color table unit B24. To perform translucent processing, and supply the color data of the calculation result to an external display device B22. This graphics engine also includes a character ROM B2, a palette RA
MB15, demultiplexer B8, selector B14,
B22, flip-flops B16 to B19 AND circuit B
23.

When performing graphics processing with this graphics engine, first, the system reset signal S2
Is activated, and the control unit B4 is reset. next,
The CPU_I / F signal S1 is sent from the CPU B1 to the control unit B4.
Is output to the control unit B4 and the graphics engine unit B3. At this time, the control unit B4 receives the pseudo color table by the CPU_I / F signal S1 from the CPU B1, outputs a pseudo color table input signal S43, and stores the received pseudo color table in the pseudo color table unit B24. Further, the control unit B4 sends the display device B22.
With respect to the synchronization signal S1 as shown in step ST2.
2 is output. Thus, the initialization processing as shown in step ST3 starts.

In the initialization processing, the control unit B4
The initialization signal S40 is activated to output an empty signal from the demultiplexers B8 and B9. The graphics engine unit B3 activates the stored image WEB S10 according to the control signal S6 from the control unit B4, sequentially increments the stored image address S9, and sets all palette [i] prepared in the image buffers B11 and B12. empty for [j], yusen [i] [j], half [i] [j]
Set.

At the same time, the control section B4 outputs the control signal S
In accordance with 6, the image data of the last image is output from the graphics engine unit B3, and the group number S41 extracted therefrom is sequentially stored in the image buffer B13 according to the storage image address S9. When the initialization process is completed, the storage process as shown in step ST4 is started.

In the storing process, the control unit B4 operates the CPU B
According to the CPU_I / F signal S1 output from the CPU 1, an engine control signal S6 is output to the graphics engine unit B3 as a parameter required for a figure to be displayed. The graphics engine unit B3 calculates the ROM address S3 from the parameter given by the engine control signal S6, and outputs it to the character ROM B2. Character R
OM B2 is R from graphics engine unit B3.
The ROM data S4 is returned to the graphics engine B3 according to the OM address S3.

The graphics engine section B3 stores the set value and the returned R at the start of the graphics processing.
According to the OM data S4, the image data S5 is sequentially output to the image buffers B11 to B13, and the engine output image WEB S7 and the engine output image address S8 are sequentially output to the control unit B4. Here, the image data S5 is a palette, yuse
It is data composed of three elements, n and half.

Next, the comparator B5 compares yusen included in the image data S5 with yusen included in the image buffer output signal S30 output from the image buffer B11, and performs priority switching according to the comparison result. The signal S22 is output. In accordance with the priority switching signal S22, the demultiplexer B8 outputs the higher one of the image data S5 and the image buffer output signal S30 as the image buffer input signal S25, and outputs the lower one as the next image buffer comparison data S26. Here, the image buffer B11
Stores the image buffer input signal S25.

Next, the comparator B7 compares the yusen included in the next image buffer comparison data S42 with the image buffer B13.
And outputs a priority switching signal S23 according to the comparison result. If the next image buffer comparison data S42 has a higher priority according to the priority switching signal S23, the selector B10 outputs this as the image buffer input signal S31 and stores it in the image buffer B13. Otherwise, the image buffer output signal S
26 is stored in the image buffer B13 again. The above operation is repeated for images of all pixels and all surfaces.

In the display process, the control unit B4 stores the stored image address S9 given to the image buffers B11 to B13.
Are sequentially incremented from 0, and the image buffer B
Image data (image buffer output signals S30, S31, group signal S14) sequentially from pixel 11 to B13 in pixel units
Is output. The selector B14 is an image buffer B
11 and B12, the pallet address S3 from the image buffer output signals S30 and S31 respectively output.
3 and S34 are extracted, and the pallet address S32 is sequentially output to the pallet RAM B15 according to the pallet control signal S11 from the control unit B4.

The palette RAM B15 outputs color data S36 according to the supplied palette address S32, and sequentially stores the data in the flip-flops B16 and B18 according to the palette control signal S11 from the control unit B4. Also, the pallet control signal S from the control unit B4
11, the translucency S37, S38, and S43 of the image buffer output signals S26 to S28 output from the image buffers B11 to B13 are changed to the flip-flop B1.
7 and B19, respectively.

At the same time, the control section B4 uses the group signal S14 output from the image buffer B13 as the pseudo color table input signal S43 to generate the pseudo color table section B24.
Output to Thus, the pseudo color table B24 sequentially outputs the pseudo color data S15 corresponding to the group.

Then, the α blending operation unit B21
Are the color data stored in the flip-flops B16 and B18, the translucency stored in the flip-flops B17 and B19, respectively, and the pseudo color table section B2.
A predetermined operation is sequentially performed on the color data of the pseudo color output from No. 4 to perform a translucent process. The α blending calculator B21 sequentially outputs the calculation result to the display device B22 as color data S40 of an image to be displayed.
When the color data S40 is output for all the addresses in this way and the display processing is completed, the control section B4 outputs the synchronization signal S12 again, and further performs the initialization processing.

The present invention is not limited to the above embodiment,
Various modifications and applications are possible. Hereinafter, modifications of the above-described embodiment applicable to the present invention will be described.

In the above embodiment, the graphics engine having the configuration shown in FIG. 9 has been exemplified as a dedicated graphics engine for executing the graphics processing. However,
If the graphics processing in the above embodiment can be realized, the configuration of the dedicated graphics engine is
It is not limited to these.

In the above embodiment, the program shown in each flowchart is stored in the storage device 12,
U11 was to do this. However, as shown in FIG. 10A, these programs are stored in a computer-readable recording medium such as a CD-ROM 40, distributed, read by the disk reading device 4, and stored in the storage device 12. It may be.

[0104] These programs are shown in FIG.
As shown in (b), a distribution request is sent from the communication device 5 to the server 51 via the network 50, and the communication device 5 receives the distribution request from the server 51 as a program data signal superimposed on a carrier wave and stores the program data signal in the storage device 12. It may be a thing.

[0105]

As described above, according to the present invention,
In general, the last image having a translucency of 1 is stored in a specific image buffer, so that the image displayed on the display device always takes into account the color of the last image. Become. For this reason, even if the translucency of the image in front of it is all low, a large error does not occur between the color of the actually displayed image and the color to be displayed originally.

Further, by providing a pseudo color table, data stored in a specific image buffer can be smaller than the color data of the last image, so that the capacity of the image buffer can be reduced. Can be.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a computer system applied to an embodiment of the present invention.

FIG. 2 is a flowchart showing a pseudo color table creation process executed prior to a graphics process in the embodiment of the present invention.

FIG. 3 is a diagram schematically illustrating a pseudo color table created by the process of FIG. 2;

FIG. 4 is a flowchart illustrating graphics processing according to the embodiment of the present invention.

FIG. 5 is a flowchart showing the initialization processing of FIG. 4 in detail.

FIG. 6 is a flowchart showing the storage processing of FIG. 4 in detail.

FIG. 7 is a flowchart showing the display processing of FIG. 4 in detail.

FIG. 8 is a diagram illustrating graphics processing according to the embodiment of the present invention.

FIG. 9 is a block diagram illustrating a configuration of a graphics engine that implements graphics processing according to the embodiment of the present invention.

FIGS. 10A and 10B are block diagrams showing a configuration of a computer system applied as a modification of the embodiment of the present invention.

FIG. 11 is a flowchart showing an initialization process in a conventional example.

FIG. 12 is a flowchart showing a storage process in a conventional example.

FIG. 13 is a flowchart showing a display process in a conventional example.

FIG. 14 is a block diagram illustrating a configuration of a graphics engine that implements graphics processing of a conventional example.

FIG. 15 is a diagram illustrating graphics processing in a conventional example.

[Explanation of symbols]

 Reference Signs List 1 computer 2 input device 3 display device 4 disk reading device 5 communication device 11 CPU 12 storage device 40 CD-ROM 50 network 51 server B1 CPU B2 character ROM B3 graphics engine unit B4 control unit B5, B6 comparator B8 demultiplexer B9 Selector B11-B13 Image buffer B14 Selector B15 Palette RAM B16-B19 Flip-flop B21 α blending calculator B22 Display device B24 Pseudo color table section

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5B057 AA20 CA08 CA12 CA16 CB08 CB12 CB16 CE08 CE20 DA16 DB02 DB09 5C082 AA36 BA14 BA27 BB11 CA56 CA81 CB10 DA01 MM00

Claims (12)

[Claims] 1. An n which is a target of an overlay display process
A graphic for storing a predetermined image from m images in m (m <n) image buffers and processing the images stored in the m image buffers to generate image data for display on a display device A m-image buffer for initializing the m image buffers and identifying a last image of the n-images to be subjected to the superimposition display processing from the m image buffers. Initialization means for storing a predetermined image other than the last image among the n-images to be subjected to the superimposition display processing, to a predetermined image other than the specific one of the m image buffers. A storage unit for storing, an image stored in a specific image buffer by the initialization unit, and an image stored in an image buffer other than a specific image buffer by the storage unit, and displayed on a display device. Graphics processing apparatus comprising: a display processing means for generating display data. 2. A pseudo color table storage means for storing a pseudo color table in which a predetermined number of pseudo color data and color data included in each pseudo color data are registered in association with each other, The display processing means stores data corresponding to the last image among the n-surface images to be subjected to the combined display processing in the specific one of the m image buffers. The pseudo-color data stored in the pseudo-color table storage means corresponding to the data stored in the pseudo-color table is subjected to arithmetic processing with the color data corresponding to the image stored in another image buffer to perform a translucent process. The graphics processing device according to claim 1, wherein: 3. A pseudo color table is generated based on the last image of the n images to be superimposed and displayed before the initialization of the image buffer by the initializing means. 3. The graphics processing apparatus according to claim 2, further comprising: a pseudo color table generation unit that stores the pseudo color table in the pseudo color table storage unit. 4. The pseudo-color table generating means extracts, as pseudo-color data, a predetermined number of color data which are frequently used in the last image of the n-images to be subjected to the superimposition display processing. The pseudo color table is generated by associating another color data included in the image on the last surface which is not extracted as the pseudo color data with any of the extracted pseudo color data. Graphics processing device as described. 5. An n which is a target of the overlay display processing
The image of the plane is given a priority order, and the storage means preferentially assigns the image with the higher priority order to the m
The graphics processing device according to claim 1, wherein the graphics processing device stores the image data in a buffer other than a specific one of the image buffers. 6. The storage means sequentially processes images other than the last one of the n-side images to be subjected to the superimposition display processing in units of pixels, and the m units of pixels are used as units. The graphics processing apparatus according to claim 1, wherein the image data is sequentially stored in a memory other than the specific image buffer. 7. A specific image buffer for storing a specific image among images to be superimposed and displayed, and a specific image buffer other than the specific image among images to be superimposed and displayed. One or more non-specific image buffers each storing an image, an arithmetic unit that performs translucent processing on the image stored in the specific image buffer and the image stored in the non-specific image buffer, A control device for storing an image in the non-specific image buffer and controlling a translucent process by the arithmetic device, wherein the control device initializes the specific image buffer and the non-specific image buffer, respectively, and superimposes The image of the last surface of the images to be displayed is stored in the specific image buffer, and is subjected to the superimposed display processing. A predetermined image is selected from images other than the last image among the images, and stored in the non-specific image buffer; and the translucent processing of the images stored in the specific image buffer and the non-specific image buffer, respectively, is performed by the calculation. The number of faces of the image targeted for the overlay display process is
A graphics processing apparatus, wherein the number of the specific image buffers and the number of the non-specific image buffers are larger than the total number. 8. A pseudo color table in which a predetermined number of pseudo color data and color data included in each of the pseudo color data are registered in association with each other, and wherein the control device is a target of an overlay display process. The arithmetic device stores data corresponding to the last image of the image in the specific image buffer, reads the pseudo color data corresponding to the data stored in the specific image buffer from the pseudo color table, 8. The graphics processing apparatus according to claim 7, wherein a translucency process is performed by performing an arithmetic process on the color data corresponding to the image stored in the specific image buffer. 9. An n which is a target of the overlay display processing
A graphic for storing a predetermined image from m images in m (m <n) image buffers and processing the images stored in the m image buffers to generate image data for display on a display device A method of initializing the m image buffers, and identifying the last image of the n images to be subjected to the superimposing display processing by specifying the m image buffers of the m image buffers. And a predetermined image other than the last one of the n-side images to be subjected to the superimposition display processing, except for the specific one of the m image buffers. A storing step of storing; an image stored in a specific image buffer in the initializing step; and an image stored in an image buffer other than the specific image buffer in the storing step, and displayed on a display device. Graphics processing method characterized by comprising a display processing step of generating display data for. 10. A pseudo-color table registering step of registering a predetermined number of pseudo-color data and color data included in each pseudo-color data in a pseudo-color table and registering the pseudo-color data in the pseudo-color table. The data corresponding to the image of the last surface among the images of the n surfaces to be processed is stored in a specific one of the m image buffers, and the display processing step stores the data in the specific image buffer. The translucent process is performed by performing arithmetic processing on the pseudo color data registered in the pseudo color table corresponding to the obtained data with color data of an image stored in another image buffer. Item 10. The graphics processing method according to Item 9. 11. A predetermined image is stored in m (m <n) image buffers from an n-plane image to be superimposed and displayed, and the images stored in the m image buffers are stored. A computer-readable recording medium that records a program for processing and generating image data for display on a display device, wherein the m image buffers are initialized, and An initialization step of storing the last image of the n-side images in a specific one of the m image buffers; and Storing a predetermined image other than the last surface of the m image buffers other than the specific one of the m image buffers; and storing the image and the case stored in the specific image buffer in the initialization step. Recording a program for causing a computer to execute a translucent process on an image stored in an image buffer other than a specific one in the step and generate display data for display on a display device. Characteristic computer readable recording medium. 12. A program for causing a computer to execute a pseudo color table registration step of associating a predetermined number of pseudo color data with color data included in each pseudo color data and registering the pseudo color table in a pseudo color table, further comprising: The initialization step stores data corresponding to the last image among the n-surface images to be subjected to the superimposition display processing in a specific one of the m image buffers. Is translucent by performing arithmetic processing on the pseudo color data registered in the pseudo color table corresponding to the data stored in the specific image buffer with the color data of the image stored in another image buffer. The computer-readable recording medium according to claim 11, which performs processing.