KR100230845B1 - Generating method of sprite animation - Google Patents

Abstract

The present invention relates to a graphics processing apparatus, and more particularly, to a sprite animation method for expressing a motion of an arbitrary two-dimensional sprite more speedily, comprising: a first step of initializing the number (N) of residual image spots to be left; 2) initializing the previous sprite index (j); Comparing the difference (i-j) of the previous sprite index from the current sprite index to the number (N) of residual image spots; If the index difference value (i-j) is larger than the number (N) of residual image spots, the corresponding j-th previous sprite is erased; Incrementing the index j of the previous sprite by 1; If the index difference value (i-j) is smaller than the number of residual image spots (N) after the fifth step or the second step, the current sprite is drawn; Storing the memory location of the current sprite; The present invention composed of eight steps of incrementing the index (i) of the current sprite by 1 and repeating the steps from the third step, displays the current stripe and the previous stripe together to continuously display the motion, Or when blurring effects are particularly needed.

Description

Generating method of sprite animation

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphics processing apparatus, and more particularly, to a sprite animation method for expressing the motion of any two-dimensional sprite more quickly.

As the automation progresses and the development into the information society progresses, the application fields of computer graphics are rapidly expanding, and the animation processing technology for processing two-dimensional and three-dimensional graphics in real time is being actively developed. In order to create a realistic and lively image using this graphics processing technology, a high-resolution display (1280 × 1024) is required. When performing transformation and color calculation for more than one million pixels, Calculation is required.

FIG. 1 is a block diagram showing an example of a general graphics system. FIG. 1 is a block diagram showing a general graphics system. The general-purpose central processing unit (CPU) 2 is connected to the system bus 1 and performs overall programs. A system memory 3 for storing data required by the apparatus, a graphic board 4 connected to the system bus for processing graphics, and a monitor 5 for displaying a video signal provided from the graphics board .

The graphics board 4 includes a graphics processor 4-1, a graphics processor memory 4-2, a frame buffer 4-3, and a video processor 4-4.

The graphics processor 4-1 collectively executes processors related to graphics processing.

The graphics processor memory 4-2 stores various data and programs required by the graphics processor.

The frame buffer 4-3 stores data for display completed by the graphics processor.

The video processor 4-4 processes the data stored in the frame buffer to be displayed on the monitor 5.

FIG. 2 shows an example of a process of displaying data of the frame buffer on a monitor. The frame buffer has 8 bits per pixel, and 8 bits are a palette storing a pixel value of an actual pixel ). Accordingly, the palette has 256 colors and 4 bits are allocated to red, green, and blue, respectively. A pixel value (100110100001) of the pixel is assigned to the monitor according to the address (67: 01000011) of the frame buffer .

On the other hand, animation is literally a life-giving work. When you take a scene of a moving scene and display it at a high speed, the animation realizes that the object actually moves due to an optical illusion. For example, a cartoon film draws 24 frames per second, and a TV 30 frames per second, which increases the effect by processing the number of frames that need to be drawn per second, depending on the speed of the moving object.

In the case of computer-based animation, the processing speed of the computer becomes a problem, and a higher processing speed is required to process a large number of frames per second. Especially, since the animation at that time is different according to the input speed of the user who moves the object, a processing method is also needed.

Especially, in order to show the animation effect, an animation technique which can express the motion of the object by the hardware is also called 'sprite animation', wherein the sprite resides in the frame buffer storing the video level data It points to a small amount of memory. The position of this sprite is always specified in the frame buffer register, and the value of this register is changed by the motion of the sprite on the screen.

Here, the term 'sprite' was first used by Apple in the 1970s, and it is widely used in the sense of pointing directly at the 'moving object' that has passed through the background screen in addition to the small amount of memory in the frame buffer.

The concept of the sprite used here is a form in which the part other than the drawn part is visible even if it is superimposed on another picture (background) like the drawing on the glass plate, and it is used as the latter meaning (moving object).

Computers with a sprite engine that provides sprite processing directly in hardware are being built, while IBM PCs do not have the hardware to provide sprite, so the software must support sprite.

When the sprite is implemented through software, the data structure of the sprite is used as a two-dimensional structure having a length and a vertical length equal to the structure of a screen or a one-dimensional structure because the memory is a one-dimensional structure. , NOT, XOR), and the like.

Particularly, the XOR technique, which is useful, uses a result obtained by performing a bitwise OR operation on the bits of the current pixel value in the frame buffer as a new value, and uses the inverse of the exclusive OR operation to shift the movement of an arbitrary pixel or block pixel Express.

That is, if an arbitrary pixel value is XORed twice in an empty frame buffer, the object is drawn in the first XOR operation and then erased again in the second XOR operation. Here, if you move the position of the object to be redrawn a little, you feel like the object moves.

In addition, an object is erased by performing an XOR operation (exclusive logical sum operation) on the object of the previous frame, and then an OR operation (OR operation) is performed on the new frame to re-draw the object to express the moving object.

Such a conventional technique has a problem in that it is not enough to feel a rapid sense of speed when the sprites on the screen are moving, erasing the sprites in the previous frame every time and re-drawing the sprites in the new frame.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a method of generating a sprite animation by storing position information of a plurality of previous frames, The purpose is to do.

According to an aspect of the present invention, there is provided a method for initializing a residual sprite number (N) 2) initializing the previous sprite index (j); Comparing the difference (i-j) of the previous sprite index from the current sprite index to the number (N) of residual image spots; If the index difference value (i-j) is larger than the number (N) of residual image spots, the corresponding j-th previous sprite is erased; Incrementing the index j of the previous sprite by 1; If the index difference value (i-j) is smaller than the number of residual image spots (N) after the fifth step or the second step, the current sprite is drawn; Storing the memory location of the current sprite; And incrementing the index (i) of the current sprite by 1, and repeating the above steps from the above step (3).

1 is a block diagram showing an example of a general computer graphics system,

2 is a diagram illustrating a process of displaying data of the frame buffer;

3 is a flow chart illustrating a method of displaying a residual image sprite in accordance with the present invention.

Hereinafter, the functions and effects of the present invention will be described in detail.

The method of the present invention is shown in FIG. 3 to achieve the above object.

3, N is a variable representing the number of frames of the desired sprite for the afterimage effect on the screen, i is the index of the current sprite showing the last movement, j is the previous The index of the sprite.

As shown in FIG. 3, in the first step S1, the frame number N of the residual image sprite to be left is initialized, and in the second step S2, the index j of the sprite to be initially drawn is initialized to one.

In the third step S3, the difference ij of the previous sprite index j from the current sprite index i is compared with the number of residual sprite N. In the fourth step S4, (Ij) of the index is larger than the number (N) of residual image spots, the j-th previous sprite is erased.

In the fifth step S5, the index j of the previous sprite is incremented by 1. In the sixth step S6, the difference ij in the index of the comparison result after the step S5 or after the step S5 is equal to If the number of residual sprite is smaller than the number (N), the i-th current sprite is drawn.

In the seventh step S7, the memory location of the i-th current sprite is stored. In the eighth step S8, the index i of the current sprite is incremented by one and the process is repeated from the third step S3.

For example, we explain the process of displaying on-screen sprites assuming three residual sprites to be left for blurring and afterimage effects.

Sprites with changes in motion over time are stored in memory.

Here, the sequence in which the moving sprite is drawn is drawn from the smallest index of the sprite, and then the sprite of the next index is drawn.

The sprite index corresponding to the real time t is the index of the current sprite frame, the current sprite index i is updated in the register A, and the previous sprite index j is updated in the register B.

In displaying the initial sprite, when the time t is 1, the sixth step (S6) is performed after the determination of the third step (S3), and the bit map of the current one sprite is OR computed in the destination register of the video RAM, Lt; / RTI > Then, the position of the memory in which the first sprite is stored is stored in the first-in first-out buffer (FIFO) (S7). Now, the value of the register A is incremented by one to make the current sprite index 2, and as a result of the third step, the second sprite is displayed on the screen in the same manner as the first sprite is displayed. Also, the position of the memory in which the second sprite is stored is stored in the first-in first-out buffer.

Subsequently, the same process as that for displaying the first sprite is performed until the value of the register A becomes 4.

That is, when t = 1, one sprite is displayed. When t = 2, one sprite is displayed. When t = 3, one sprite is displayed. When t = 4, one sprite is displayed. , 2, 3, and 4 sprites are displayed. The position of the frame stored in the first-in-first-out buffer (FIFO) is the memory location of the fourth, third, second, and first sprites.

(Ij = 5-1 = 4) of the previous sprite index from the current sprite index as a result of the third step (S3) when the register A value is 5 and the register B value is 1 at t = Is larger than 3 (= N), the fourth step S4 is performed to XOR the previous bitmap of the previous bit to the destination register of the video RAM to erase the first bit of the sprite.

Here, the position of the first sprite is extracted from the first-in-first-out buffer, and the position is searched for. Then, the fifth step S5 is performed to increase the previous sprite index j by 1, and the value of the register B becomes 2. Then, in the sixth step S6, the bit map of the current 5th sprite is ORed in the destination register of the video RAM, and the memory location of the current 5th sprite is stored in the first-in first-out buffer.

In this case, the frame positions stored in the first-in first-out buffer are the memory locations of the sprites # 5, # 4, # 3 and # 2.

Then, the eighth step S8 is performed to increase the current sprite index i by 1, and the value of the register A is set to 6, and the third step S3 is repeated.

(Ij = 6-2 = 4) of the previous sprite index from the current sprite index as a result of the third step (S3) when the register A value is 6 and the register B value is 2 at t = 6, Since the number of residual images is larger than 3 (= N), the fourth step is performed to erase the second sprite by performing an XOR operation on the second sprite bitmap in the destination register of the video RAM.

Here, the position of the second sprite is extracted from the first-in-first-out buffer, and the position is searched for. Then, the fifth step S5 is performed to increase the previous sprite index j by 1, and the value of the register B becomes 3. [ Then, in a sixth step S6, the bit map of the current 6th sprite is OR-operated on the destination register of the video RAM to display on the screen, and the memory location of the current 6th sprite is stored in the first-in first-out buffer.

In this case, the frame positions stored in the first-in first-out buffer are the memory locations of the sprites # 6, # 5, # 4 and # 3.

The sprites displayed in the flow of time are shown in the table above.

t i (current sprite) j (old sprite) FIFO Displayed Sprite One One One #One One 2 2 One # 2, # 1 1,2 3 3 One # 3, # 2, # 1 1,2,3 4 4 One # 4, # 3, # 2, # 1 1,2,3,4 5 5 2 # 5, # 4, # 3, # 2 2,3,4,5 6 6 3 # 6, # 5, # 4, # 3 3,4,5,6 7 7 4 # 7, # 6, # 5, # 4 4,5,6,7

As can be seen from the above table, the current sprite is continuously drawn from t = 1 to t = 4, and the sprites of the remaining frames excluding the three previous frames from the current frame are erased from t = 5, To display the sprite.

Here, the position information on the previous frame to be erased uses the first-in first-out buffer, and in this embodiment, 4 (= N + 1) number of shift registers are sufficiently implemented.

You can also track the overall motion trajectory by increasing the number of afterimages you want to leave the moving sprite.

If you want to show the elapsed time of the second hand or the minute hand by turning the clock fast through the above operation, or if it is necessary to have a car or a train slip at high speed to get a faint look, leave a trace of the sprite If you perform blurring, you will feel a sense of speed.

As described above, according to the present invention, since the current stripe is displayed up to the previous stripe and the motion is continuously displayed, effective use can be made when a speed sense is required in the animation generation process or when a blurring effect is particularly needed.

Claims (1)

A method of creating animation for causing a velocity and a blurring effect of a sprite, (S1) of initializing the number (N) of residual image sprites to be left; (S2) initializing the previous sprite index (j); (S3) of comparing the difference (i-j) of the previous sprite index from the current sprite index to the number (N) of residual sprite numbers; If the index difference value (i-j) is greater than the number of residual image spots (N), the corresponding j-th previous sprite is deleted (S4). Step S5 of incrementing the index j of the previous sprite by 1; If the index difference value (i-j) is smaller than the residual image sprite count (N) after step 5 or step 2, the current sprite is drawn (step S6); Step 7 (S7) of storing the memory location of the current sprite; (S8) of incrementing the index (i) of the current sprite by 1 and repeating the step (3) from the step (3).