KR20160029550A - Mobile terminal and method for controlling the same - Google Patents

Abstract

The present invention relates to a mobile terminal which performs three-dimensional rendering. The mobile terminal comprises: an external memory for storing texture data; a sharing memory for pre-withdrawing the texture data by a mipmap unit from the external memory to store the same; and a graphic processing device for performing texture mapping based on the texture data stored in the sharing memory.

Description

[0001] MOBILE TERMINAL AND METHOD FOR CONTROLLING THE SAME [0002]

The present invention relates to a mobile terminal and a control method thereof, and more particularly, to a mobile terminal for prefetching texture data using a shared memory and a control method thereof.

A terminal can be divided into a mobile / portable terminal and a stationary terminal depending on whether the terminal is movable or not. The mobile terminal can be divided into a handheld terminal and a vehicle mounted terminal according to whether the user can directly carry the mobile terminal.

The functions of mobile terminals are diversified. For example, there are data and voice communication, photographing and video shooting through a camera, voice recording, music file playback through a speaker system, and outputting an image or video on a display unit. Some terminals are equipped with an electronic game play function or a multimedia player function. In particular, modern mobile terminals can receive multicast signals that provide visual content such as broadcast and video or television programs.

Such a terminal has various functions, for example, a multimedia player having a complex function such as photographing or moving picture shooting, reproduction of music or video file, reception of game or broadcasting, . In order to implement complex functions, mobile terminals implemented in the form of multimedia devices are being applied variously in terms of hardware and software.

Meanwhile, recent mobile terminals are providing various applications based on 3D computer graphics. In contrast to 2D computer graphics, 3D computer graphics is a three-dimensional representation of the geometric data of a model stored in a computer (each point is stored using spatial coordinates with three axes of height, width, and depth) It is a computer graphics technology that processes and outputs as a dimensional result.

The three-dimensional computer graphics are largely achieved through a three-dimensional modeling process, an animation process, and a three-dimensional rendering process. Texture mapping (TM) techniques are inevitably used in the 3D rendering process.

Texture mapping is one of the most successful and popular technologies in the 3D graphics pipeline to impart realism to computer generated scenes. A typical texture mapping process results in highly intensive access to external memory because the nature of the texture mapping process involves a number of texture searches. Thus, frequent texture retrieval causes bottlenecks on the memory bus.

To alleviate this problem, the GPU (Graphic Processing Unit) has a texture cache. The texture cache is provided to eliminate redundancy in fetching texels from external memory and utilizes the natural spatial locality of triangle's rasterization. However, since the capacity of the texture cache is limited, it can not be a fundamental solution to the bottleneck. Therefore, when texture mapping is performed, a method for more efficiently retrieving texture data stored in the external memory is desperately required.

The present invention is directed to solving the above-mentioned problems and other problems. Another object of the present invention is to provide a mobile terminal for prefetching texture data by using a shared memory in texture mapping, and a control method thereof.

According to an aspect of the present invention, there is provided a mobile terminal for performing three-dimensional rendering, comprising: an external memory for storing texture data;

A shared memory for prefetching the texture data from the external memory in units of mipmaps; And a graphics processing device for performing texture mapping based on the texture data stored in the shared memory.

Effects of the mobile terminal and the control method according to the present invention will be described as follows.

According to at least one embodiment of the present invention, texture data is prefetched from an external memory in units of mipmaps and stored in a shared memory, thereby enabling fast memory access in texture mapping, thereby improving rendering performance of 3D graphics There are advantages.

Meanwhile, various other effects will be directly or implicitly disclosed in the detailed description according to the embodiment of the present invention to be described later.

1 is a block diagram illustrating a mobile terminal according to the present invention;
Figure 2 is a block diagram illustrating a mobile application processor associated with the present invention;
3 is a block diagram illustrating a graphics processing apparatus according to an exemplary embodiment of the present invention;
4 is a block diagram illustrating a 3D graphics pipeline according to one embodiment of the present invention;
5 is a diagram referred to describe an external memory including three-dimensional graphics applications A1 to AZ;
FIG. 6 is a diagram referred to explain a texture mapping technique and a mipmapping technique used in 3D rendering; FIG.
FIG. 7 and FIG. 8 are diagrams for describing a method of pre-exporting texture data using a shared memory according to a first embodiment of the present invention; FIG.
FIGS. 9 and 10 are diagrams for describing a method for pre-exporting texture data using a shared memory according to a second embodiment of the present invention; FIG.
FIGS. 11 and 12 are diagrams for describing a method of pre-exporting texture data using a shared memory according to a third embodiment of the present invention; FIGS.
FIGS. 13 and 14 are diagrams for describing a method for pre-exporting texture data using a shared memory according to a fourth embodiment of the present invention; FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to designate identical or similar elements, and redundant description thereof will be omitted. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. , ≪ / RTI > equivalents, and alternatives.

The mobile terminal described in this specification includes a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a slate PC A tablet PC, an ultrabook, a wearable device such as a smartwatch, a smart glass, and a head mounted display (HMD). have.

However, it will be appreciated by those skilled in the art that the configuration according to the embodiments described herein may be applied to fixed terminals such as a digital TV, a desktop computer, a digital signage, and the like, will be.

1 is a block diagram illustrating a mobile terminal according to the present invention.

1, a mobile terminal 100 includes a wireless communication unit 110, an input unit 120, a sensing unit 140, an output unit 150, an interface unit 160, a memory 170, a controller 180, And a power supply unit 190 and the like. The components shown in FIG. 1 are not essential for implementing a mobile terminal, so that the mobile terminal described herein may have more or fewer components than the components listed above.

The wireless communication unit 110 may be connected between the mobile terminal 100 and the wireless communication system or between the mobile terminal 100 and another mobile terminal 100 or between the mobile terminal 100 and the external server 100. [ Lt; RTI ID = 0.0 > wireless < / RTI > In addition, the wireless communication unit 110 may include one or more modules for connecting the mobile terminal 100 to one or more networks.

The wireless communication unit 110 may include at least one of a broadcast receiving module 111, a mobile communication module 112, a wireless Internet module 113, a short distance communication module 114, and a location information module 115 .

The input unit 120 includes a camera 121 or an image input unit for inputting a video signal, a microphone 122 for inputting an audio signal, an audio input unit, a user input unit 123 for receiving information from a user A touch key, a mechanical key, and the like). The voice data or image data collected by the input unit 120 may be analyzed and processed by a user's control command.

The sensing unit 140 may include at least one sensor for sensing at least one of information in the mobile terminal, surrounding environment information surrounding the mobile terminal, and user information. For example, the sensing unit 140 may include a proximity sensor 141, an illumination sensor 142, a touch sensor, an acceleration sensor, a magnetic sensor, A G-sensor, a gyroscope sensor, a motion sensor, an RGB sensor, an infrared sensor, a finger scan sensor, an ultrasonic sensor, A microphone 226, a battery gauge, an environmental sensor (for example, a barometer, a hygrometer, a thermometer, a radiation detection sensor, A thermal sensor, a gas sensor, etc.), a chemical sensor (e.g., an electronic nose, a healthcare sensor, a biometric sensor, etc.). Meanwhile, the mobile terminal disclosed in the present specification can combine and utilize information sensed by at least two of the sensors.

The output unit 150 includes at least one of a display unit 151, an acoustic output unit 152, a haptic tip module 153, and a light output unit 154 to generate an output related to visual, auditory, can do. The display unit 151 may have a mutual layer structure with the touch sensor or may be integrally formed to realize a touch screen. The touch screen may function as a user input unit 123 that provides an input interface between the mobile terminal 100 and a user and may provide an output interface between the mobile terminal 100 and a user.

The interface unit 160 serves as a path to various types of external devices connected to the mobile terminal 100. The interface unit 160 is connected to a device having a wired / wireless headset port, an external charger port, a wired / wireless data port, a memory card port, And may include at least one of a port, an audio I / O port, a video I / O port, and an earphone port. In the mobile terminal 100, corresponding to the connection of the external device to the interface unit 160, it is possible to perform appropriate control related to the connected external device.

In addition, the memory 170 stores data supporting various functions of the mobile terminal 100. The memory 170 may store a plurality of application programs or applications running on the mobile terminal 100, data for operation of the mobile terminal 100, and commands. At least some of these applications may be downloaded from an external server via wireless communication. Also, at least a part of these application programs may exist on the mobile terminal 100 from the time of shipment for the basic functions (e.g., telephone call receiving function, message receiving function, and calling function) of the mobile terminal 100. Meanwhile, the application program may be stored in the memory 170, installed on the mobile terminal 100, and may be operated by the control unit 180 to perform the operation (or function) of the mobile terminal.

In addition to the operations related to the application program, the control unit 180 typically controls the overall operation of the mobile terminal 100. The control unit 180 may process or process signals, data, information, and the like input or output through the above-mentioned components, or may drive an application program stored in the memory 170 to provide or process appropriate information or functions to the user.

In addition, the controller 180 may control at least some of the components illustrated in FIG. 1 in order to drive an application program stored in the memory 170. In addition, the controller 180 may operate at least two of the components included in the mobile terminal 100 in combination with each other for driving the application program.

The power supply unit 190 receives external power and internal power under the control of the controller 180 and supplies power to the components included in the mobile terminal 100. The power supply unit 190 includes a battery, which may be an internal battery or a replaceable battery.

At least some of the components may operate in cooperation with one another to implement a method of operation, control, or control of a mobile terminal according to various embodiments described below. In addition, the operation, control, or control method of the mobile terminal may be implemented on the mobile terminal by driving at least one application program stored in the memory 170. [

Next, a communication system that can be implemented through the mobile terminal 100 according to the present invention will be described.

First, the communication system may use different wireless interfaces and / or physical layers. For example, wireless interfaces that can be used by a communication system include Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA) ), Universal mobile telecommunication systems (UMTS) (in particular Long Term Evolution (LTE), Long Term Evolution-Advanced (LTE-A)), Global System for Mobile Communications May be included.

Hereinafter, for the sake of convenience of description, the description will be limited to CDMA. However, it is apparent that the present invention can be applied to all communication systems including an OFDM (Orthogonal Frequency Division Multiplexing) wireless communication system as well as a CDMA wireless communication system.

A CDMA wireless communication system includes at least one terminal 100, at least one base station (BS) (also referred to as a Node B or Evolved Node B), at least one Base Station Controllers (BSCs) , And a Mobile Switching Center (MSC). The MSC is configured to be coupled to a Public Switched Telephone Network (PSTN) and BSCs. The BSCs may be paired with the BS via a backhaul line. The backhaul line may be provided according to at least one of E1 / T1, ATM, IP, PPP, Frame Relay, HDSL, ADSL or xDSL. Thus, a plurality of BSCs may be included in a CDMA wireless communication system.

Each of the plurality of BSs may comprise at least one sector, and each sector may comprise an omnidirectional antenna or an antenna pointing to a particular direction of radial from the BS. In addition, each sector may include two or more antennas of various types. Each BS may be configured to support a plurality of frequency assignments, and a plurality of frequency assignments may each have a specific spectrum (e.g., 1.25 MHz, 5 MHz, etc.).

The intersection of sector and frequency assignment may be referred to as a CDMA channel. The BS may be referred to as a base station transceiver subsystem (BTSs). In this case, a combination of one BSC and at least one BS may be referred to as a "base station ". The base station may also indicate a "cell site ". Alternatively, each of the plurality of sectors for a particular BS may be referred to as a plurality of cell sites.

A broadcast transmission unit (BT) transmits a broadcast signal to terminals 100 operating in the system. The broadcast receiving module 111 shown in FIG. 1 is provided in the terminal 100 to receive a broadcast signal transmitted by the BT.

In addition, a Global Positioning System (GPS) may be associated with the CDMA wireless communication system to identify the location of the mobile terminal 100. The satellite aids in locating the mobile terminal 100. Useful location information may be obtained by two or more satellites. Here, the position of the mobile terminal 100 can be tracked using all the techniques capable of tracking the location as well as the GPS tracking technology. Also, at least one of the GPS satellites may optionally or additionally be responsible for satellite DMB transmission.

Hereinabove, the components of the mobile terminal 100 according to the present invention have been described with reference to FIG. Hereinafter, a mobile terminal and a control method thereof for prefetching texture data using a shared memory according to various embodiments of the present invention will be described in detail.

2 is a block diagram illustrating a mobile application processor associated with the present invention.

Referring to FIG. 2, the mobile terminal 100 may typically provide bi-directional communication over a receive path and a transmit path.

On the receive path, the signals transmitted by the base station are received by the antenna and provided to the receiver 10. The receiver 10 conditions and digitizes the received signal and provides samples to the mobile AP 20 for further processing.

On the transmission path, the transmitter 30 receives the data transmitted from the mobile AP 20, processes and conditions it, generates a modulated signal, and transmits the modulated signal to the base station via the antenna.

The mobile AP 20 includes a modem processor 21, a video processor 22, a controller processor 23, a display processor 24, a digital signal processor (DSP) 25, a graphics processing unit (GPU) 26, Interface devices and memory devices such as an external bus interface (EBI) 28, an external bus interface (EBI) 28, and the like. The mobile AP 20 may be configured as a system on chip in which the components 21 to 28 are embedded in one chip. On the other hand, the configuration of the mobile AP 20 shown in FIG. 2 is only an embodiment of the present invention, and does not limit the scope of the present invention. Accordingly, it will be apparent to those skilled in the art that the mobile AP 200 may include only some of the above-described components, or may further include other components than those described above.

The modem processor 21 performs processes (e.g., channel coding, modulation, demodulation, and channel decoding) for data transmission and reception. The video processor 22 performs processes for video content (e.g., still images, moving images, and dynamic text) for video applications such as camcorders, video playback, and video conferencing.

The controller processor 23 controls the overall operation of various processing devices and interface devices within the mobile AP 20. The display processor 24 performs a process of facilitating display of video, graphics, and characters on the display unit 151. [

A digital signal processor (DSP) 25 performs digital signal processing for the operation of the mobile terminal 100. A graphics processing unit (GPU) 26 performs a three-dimensional graphics process.

The internal memory (or shared memory) 26 stores data and / or instructions for various devices within the mobile AP 20. At this time, it is preferable to use an SRAM (Static Random Access Memory) as the internal memory 26.

External bus interface (EBI) 28 facilitates data transfer between mobile AP 20 (e.g., internal memory 26) and external memory 170 along a bus or data line.

3 is a block diagram for explaining a graphic processing apparatus according to an embodiment of the present invention.

3, the GPU 300 includes a GPU processor 330 having a texture cache 310, a fetch controller 335, and a 3D graphics pipeline 340. In addition, the GPU 300 may additionally include a victim cache 320.

The texture cache 310 is a cache for fetching and storing texels in units of cache blocks from the external memory 170. The sacrificial cache 320 is a cache for storing the texels in the texture cache 310, Which is used to maintain a block that has escaped from the cache.

GPU processor 330 controls the overall operation of the computer graphics process. The fetch controller 335 is provided to generate a command to fetch the texture data.

The 3D graphics pipeline 340 performs a step-wise process for rendering a three-dimensional image as a two-dimensional raster image in three-dimensional computer graphics.

4, the 3D graphics pipeline 340 includes at least two stages of pipelining, i.e., a vertex processing step 341 and a pixel rendering step 342, (342). In operation, the vertex processing step 341 may include a subset of all functions or functions that are currently implemented in OpenGL, OpenGL ES, or DirectX.

Pixel rendering step 342 includes rasterization, blending and texture application operations 343 and hidden surface removal operations 344. In addition, pixel rendering step 342 may include other operations defined by OpenGL® or OpenGL®ES. The pixel rendering step 342 converts the information about the 3D object from the vertex processing step 341 into a bitmap that can be displayed on the display unit 151. [

In addition, pixel rendering step 342 processes the input triangles to produce a pixel representation of the 3D graphic image. During rasterization, blending and texture application operations 343, the texture mapping engine 343a performs texturing operations.

5 is a diagram referred to explain an external memory including three-dimensional graphics applications A1 to AZ.

5, applications A1 through AZ stored in external memory 170 may include game applications or other 3D graphics applications. Each application has one or more texture data associated therewith.

Texture mapping is a shading technique that maps a 2D texture image to a surface of a 3D object through at least one texture data. The 2D texture image used for texture mapping is stored in the external memory 170. [ Accordingly, when texture mapping is performed, if the desired texture data is not stored in the texture cache 310, the GPU 300 accesses the external memory 170 to fetch the corresponding texture data. While the individual elements of the generic image are referred to as pixels, the individual elements of the texture image are referred to as texels.

6 is a diagram referred to explain a texture mapping technique and a mipmapping technique used in 3D rendering.

In 3D rendering, texture mapping technique most commonly used is a technique of mapping a two-dimensional texture image to a three-dimensional modeling object. 6 (a), a two-dimensional texture image 620 is mapped onto a three-dimensional sphere 610 to form a sphere 630 into which a texture is mapped. To implement this in Open GL, we first need to convert the coordinates of the 2D texture image to the coordinates of the 3D object.

For high-quality 3D rendering, high-resolution texture images are required, and various types of texture images are needed to provide various graphic effects. Therefore, since this texture mapping requires high memory traffic, access to external memory is an indispensable element for improving the performance of 3D rendering. Especially, it is a very important factor in SoC or CPU / GPU fused architecture with limited memory bandwidth.

On the other hand, in the texture mapping, the most popular mip mapping technique is a technique of forming a pyramid of a texture reduced by resolution and applying it to texture mapping. 6B, when the object is located close to the object, the high-resolution texture mipmap 640 is used. When the object is located far away, the low-resolution texture mipmap 650 is used . This mipmapping technique is widely used for improving quality and speed of texture mapping in three-dimensional computer graphics.

A mipmap is a set of bitmap images made up of basic textures and textures that have been previously reduced in size for the purpose of improving rendering speed. The mipmap data is stored in the external memory 170 as a kind of texture data and provided to the internal memory 27 at the time of texture mapping.

Each bitmap image of a mipmap set is a pre-reduced size of the base texture by a certain amount. If the texture looks more than its original size, you can use the default texture, but if it looks farther or smaller than the original, use a reduced texture instead of a render. This can speed up rendering because the number of texels used in rendering is much smaller. Since mipmap images are already anti-aliased, the loss that can occur during rendering can be reduced and the load of real-time rendering can be reduced. The enlargement and reduction processes can be processed in the same way.

FIGS. 7 and 8 are views for explaining a method of pre-exporting texture data using a shared memory according to the first embodiment of the present invention.

Referring to FIGS. 7 and 8, in performing 3D rendering, the graphics processor 830 determines whether the texture data required for texture mapping is stored in the texture cache 831 (S705). That is, the graphics processing unit 830 determines whether a texture cache miss occurs for a desired texel.

If it is determined in step 705 that the texture cache miss does not occur (i.e., when a texture cache hit occurs), the graphics processor 830 fetches the texture data stored in the texture cache 831 and performs texture mapping (S745).

If it is determined in step 705 that the texture cache miss occurs, the graphics processor 830 determines whether the texture cache miss is the first miss of the texture mipmap in the current frame (step S710).

If it is determined in step 710 that the texture cache miss is the first miss of the texture mipmap, the graphics processor 830 stores the texture mipmap level in the mipmap table 832 in step S715.

The graphic processing unit 830 accesses the external memory 820 and reads the desired texture data in units of the cache block 833 (S720). The graphics processor 830 updates the texture cache 831 based on the texture data read from the external memory 820 and performs texture mapping (S740, S745).

If it is determined in step 710 that the texture cache miss is not the first miss of the texture mipmap, the graphics processor 830 determines whether the texture cache miss is the second miss of the texture mipmap in the current frame S725).

If it is determined in step 725 that the texture cache miss is the second miss of the texture mipmap, the graphics processor 830 refers to the previous access record of the texture mipmap in the mipmap table 832 in operation S730.

The graphic processing unit 830 extracts the texture data from the external memory 820 in advance to the mipmap unit 834 and stores it in the shared memory 840 (S735). At this time, the graphic processing apparatus 830 refers to the level of the texture mipmap stored in the mipmap table 832, Thereafter, the graphics processor 830 updates the texture cache 831 based on the texture data read from the shared memory 840, and performs texture mapping (S740 and S745).

If it is determined in step 725 that the texture cache miss is not the second miss of the texture mipmap, the graphics processor 830 determines whether the texture cache miss is the third or subsequent miss of the texture mipmap in the current frame (S750).

If it is determined in step 750 that the texture cache miss is a third miss due to the texture mipmap, the graphics processor 830 directly reads the texture data required for texture mapping from the shared memory 840 (S755). Then, the graphics processor 830 updates the texture cache 831 based on the texture data read from the shared memory 840, and performs texture mapping (S740, S745).

As described above, in the data line fetching method according to the first embodiment of the present invention, when one mipmap is read, a method in which a plurality of texels use 'spatial locality,' which is highly likely to read the mipmap, If the entirety of the mipmap level is likely to be read, texture data corresponding to the mipmap level is prefetched and stored in the shared memory so that fast memory access is enabled in the subsequent texture mapping.

FIG. 9 and FIG. 10 are views for explaining a method of pre-exporting texture data using a shared memory according to a second embodiment of the present invention. Hereinafter, the graphics processing apparatus according to the present embodiment will be described on the assumption that a tile-based rendering method for dividing and rendering the entire frame 1050 into tiles 1051 having a small size is used.

Referring to FIGS. 9 and 10, the graphic processing apparatus 1030 stores a texture mipmap list obtained by statistically generating texture cache misses frequently in a previous frame for each tile, in a mipmap table 1032 . For example, as shown in Table 1 below, the mipmap table 1032 stores a texture mipmap list containing textures and their mipmap levels that are frequently read for each tile.

Tile Texture mipmap list One Texture A Mipmap Levels 2, 3, 4 Texture B mipmap level 1 2
Texture A mipmap level 2, 3 Texture C mipmap level 0, 1 ... ... n Texture I Mipmap Levels 1, 2, 3 Texture J Mipmap Level 2

Upon 3D rendering for each tile, the graphics processor 1030 sequentially reads a texture mipmap list that frequently causes a texture cache miss in the previous frame from the mipmap table 1032 (S910).

The graphics processing apparatus 1030 determines whether texture data corresponding to a specific mipmap level exists in the shared memory 1040 (S920).

If it is determined in step 920 that the texture data corresponding to the specific mipmap level does not exist in the shared memory 1040, the graphics processor 1030 extracts the texture data corresponding to the mipmap level from the external memory 1020 And stored in the shared memory 1040 (S930).

If it is determined in step 920 that the texture data corresponding to the specific mipmap level exists in the shared memory 1040, the graphics processing apparatus 1030 determines whether the specific mipmap level is the last mipmap level on the texture mipmap list (S940).

If it is determined in step 940 that the specific mipmap level is not the last mipmap level on the texture mipmap list, the graphics processor 1030 proceeds to step 910 and performs the same process for the next mipmap level of the specific mipmap level .

If it is determined in step 940 that the specific mipmap level is the last mipmap level on the texture mipmap list, the graphics processor 1030 performs texture mapping of the tile (S950). More specifically, the graphics processing unit 1030 determines whether or not a texture cache miss occurs for the texture data required for texture mapping. If it is determined that the texture cache miss does not occur, the graphic processing apparatus 1030 performs texture mapping based on the texture data stored in the texture cache 1031. If the texture cache miss occurs, the graphics processor 1030 updates the texture cache 1031 based on the texture data read from the shared memory 1040, and performs texture mapping.

In step S960, the graphics processing apparatus 1030 stores a texture mipmap list obtained by statistically obtaining texture data that frequently causes a texture cache miss in the current frame, in the mipmap table 1032. [ That is, the graphics processing unit 1030 updates the texture mipmap list for the previous frame stored in the mipmap table 1032 with the texture mipmap list for the current frame.

As described above, in the data line fetching method according to the second embodiment of the present invention, when a change between frames is small, a 'temporal locality' in which a texture mipmap frequently read in a previous frame has a high probability of being read in the next frame Method, if the probability of reading the whole mipmap is high, the texture data corresponding to the mipmap level is prefetched and stored in the shared memory, thereby enabling fast memory access in the subsequent texture mapping.

FIGS. 11 and 12 are views for explaining a method of pre-exporting texture data using a shared memory according to a third embodiment of the present invention.

Referring to FIGS. 11 and 12, at the time of 3D rendering, the graphic processor 1230 designates texture data to be frequently read from the external memory 1220 and stores the texture data in the mipmap table 1232 (S1110). At this time, the programmer of the application can designate the texture data directly through API extension or the like.

The graphics processing unit 1230 checks whether the texture mipmap specified by the programmer exists in the shared memory 1240 (S1120).

If it is determined in step 1120 that the texture mipmap exists in the shared memory 1240, the graphics processing unit 1230 maintains the texture mipmap stored in the shared memory 1240 in step S1130.

If it is determined that the texture mipmap does not exist in the shared memory 1240, the graphics processing unit 1230 extracts the entire texture mipmap from the external memory 1220 and stores it in the shared memory 1240. [ (S1140).

Thereafter, the graphic processing unit 1230 determines whether a texture cache miss occurs with respect to the texture data required for texture mapping (S1150).

If it is determined in step 1150 that the texture cache miss occurs, the graphics processor 1230 updates the texture cache 1231 based on the texture data read from the shared memory 1240, and performs texture mapping (S1160 , S1170).

If it is determined in step 1150 that the texture cache hit occurs, the graphic processor 1230 performs texture mapping based on the texture data stored in the texture cache 1231 (S 1170).

As described above, in the data line fetching method according to the third embodiment of the present invention, the programmer directly stores the texture data corresponding to the specified mipmap level in the shared memory by designating and shipping the texture data, To enable fast memory access.

FIGS. 13 and 14 are diagrams for explaining a method of pre-exporting texture data using a shared memory according to a fourth embodiment of the present invention.

Referring to FIGS. 13 and 14, at the time of 3D rendering, the graphic processing unit 1430 determines whether texture data required for texture mapping is stored in the texture cache 1431 (S1310). That is, the graphics processing unit 1430 determines whether a texture cache miss occurs for the desired texel.

If it is determined in step 1310 that the texture cache miss does not occur (i.e., the texture cache hit occurs), the graphics processor 1430 fetches the texture data stored in the texture cache 1431 and performs texture mapping (S1360).

If it is determined in step 1310 that the texture cache miss occurs, the graphics processor 1430 updates the texture cache 1431 based on the texture data read from the external memory 1420 or the shared memory 1440 (S1320).

The graphics processing unit 1430 checks whether the texture data 1431 is deleted from the updated texture cache 1431 (S1330). Since the storage capacity of the texture cache 1431 is limited, when the new data is input to the texture cache 1431, the existing data corresponding to the new data is externally output.

If it is determined in step 1330 that the texture data is to be discarded in the texture cache 1431, the graphics processor 1430 deletes all texture data corresponding to the mipmap level of the extracted texture data from the external memory 1420 And stores it in the shared memory 1440 (S1340). Accordingly, the shared memory 1440 can be utilized as a kind of a victim cache.

Also, if the graphics processing unit 1430 includes a victim cache 1432, the graphics processing unit 1340 may temporarily store the evicted texture data in the victim cache 1432 (S1350). The texture data stored in the victim cache 1432 may be used for further texture mapping.

Thereafter, the graphic processing unit 1430 fetches the texture data stored in the updated texture cache 1431 and performs texture mapping (S1360).

If it is determined in step 1330 that the texture data does not exit in the texture cache 1431, the graphics processor 1430 performs texture mapping based on the texture data stored in the updated texture cache 1431 (S1360).

As described above, in the data line fetching method according to the fourth embodiment of the present invention, when the extraction of the texture data occurs in the texture cache, the texture data corresponding to the mipmap level of the extracted texture data is prefetched and stored in the shared memory Thereby enabling fast memory accesses in subsequent texture mappings.

For the sake of convenience, the data line drawing processes according to the first to fourth embodiments are illustrated as being performed by the graphic processing apparatus, but the present invention is not limited thereto. Therefore, it will be apparent to those skilled in the art that the data line fetch processors may be performed by the controller 180 or a separate controller in the mobile AP, instead of the graphics processor.

The present invention described above can be implemented as computer readable codes on a medium on which a program is recorded. The computer readable medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of the computer readable medium include a hard disk drive (HDD), a solid state disk (SSD), a silicon disk drive (SDD), a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, , And may also be implemented in the form of a carrier wave (e.g., transmission over the Internet). In addition, the computer may include a control unit 180 of the terminal. Accordingly, the above description should not be construed in a limiting sense in all respects and should be considered illustrative. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the scope of equivalents of the present invention are included in the scope of the present invention.

100: mobile terminal 110: wireless communication unit
120: input unit 140: sensing unit
150: output unit 160: interface unit
170: memory 180:
190: Power supply

Claims (6)

1. A mobile terminal performing three-dimensional rendering,
An external memory for storing texture data;
A shared memory for prefetching the texture data from the external memory in units of mipmaps; And
And a graphic processing device for performing texture mapping based on the texture data stored in the shared memory. The method according to claim 1,
Wherein the shared memory is a static random access memory (SRAM) memory. The method according to claim 1,
Wherein when the texture cache miss occurs, the graphics processor updates the texture cache based on the texture data read from the shared memory. The method according to claim 1,
Wherein the graphic processing apparatus comprises a mipmap table including information on a mipmap level of texture data required for the texture mapping. The method according to claim 1,
When the 3D rendering is performed for each tile of the current frame, the graphic processing apparatus prefetches texture data corresponding to the texture mipmap level that frequently caused the texture cache miss in the previous frame from the external memory and stores the texture data in the shared memory The mobile terminal comprising: The method according to claim 1,
Wherein the graphic processor extracts texture data corresponding to the entire mipmap level of the extracted texture data from the external memory and stores the extracted texture data in the shared memory when the texture data is exited from the texture cache. .

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