JP2010244124A - System, method and program for sharing of screen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a screen sharing system capable of displaying a window application across a plurality of display devices connected to a plurality of computers. <P>SOLUTION: In a screen sharing system in which the plurality of sets of display devices and computers are connected through a network, each computer includes a root window management table, a top window management table and a screen sharing control unit, and the screen sharing control unit of one computer transmits the plotting information and coordinate information of any section other than a region displayed on a route window displayed by a display device making a set with the computer among top windows to be displayed by the computer to the screen sharing control unit of the other computer, and when the screen sharing control unit of the other computer receives the plotting information and coordinate information of any section other than the region, the received section is displayed on the route window displayed by the display device making a set with the computer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a screen sharing system, a screen sharing method, and a screen sharing program that display one window application across a plurality of display devices connected to a plurality of computers.

  In the case of Microsoft (registered trademark) RemoteDesktop (hereinafter referred to as known technology 1) and VNC (hereinafter referred to as known technology 2), screen sharing is realized by transferring screen data of the root window. The known technique 1 can share a screen only on a Windows (registered trademark) operating system provided by Microsoft (registered trademark). Next, as known technique 2, screen sharing is possible only on an operating system that supports the RFB (Remote Framebuffer) protocol. Even if a program that supports the RFB protocol is installed on Windows (registered trademark), the top window and the background cannot be distinguished from the screen data because of the mechanism for transmitting and receiving the screen data of the root window. Therefore, window applications cannot be displayed on each other without screen switching.

  In the case of the X Window System (hereinafter referred to as known technique 3), a GUI can be used in a network transparent manner between operating systems that support the X protocol. However, since the Windows® window manager does not support the X protocol, it cannot display window applications of different operating systems. Further, since the X protocol is created for the purpose of remotely using a window application, it is not possible to display one window application across display devices connected to a plurality of computers.

  MetaVNC based on the technology of the publicly known technology 2 (hereinafter referred to as the publicly known technology 4) treats the background area other than the application window as a transparent area (also referred to as a transparent pixel), so that the local desktop can be changed between different operating systems. An application window and a remote desktop application window can be displayed on one display device. Although the known technique 4 can perform screen sharing among a plurality of computers including different operating systems, there are the following three problems.

  The first problem is that, in the RFB protocol used by VNC, the X server displays a window application at the same coordinates for two X clients, a local desktop and a remote desktop, so that the display devices arranged physically are arranged. The window cannot be displayed so as to straddle.

  The second problem is that the known technique 4 is a combination of the local desktop screen and the remote desktop screen using the full screen mode and a transparent background, so that the windows displayed on the local desktop and the individual screens displayed on the remote desktop are displayed. The window cannot be managed with one depth level (Z-Order). That is, if one of the windows of the remote desktop is selected with the mouse, all the windows of the remote desktop are displayed in front of the local desktop. In addition, for the implementation reason of performing synthesis using a transparent background, wallpaper cannot be used as the background on the X server side, and the background must be a single color.

  The third problem is that the screen data transferred for each window is not managed, and alpha blending display combining the local desktop and the remote desktop cannot be performed.

  Displaying a single window application across multiple display devices connected to multiple computers (including those with different operating systems) is a dual display system using image transfer using a virtual display driver, for example. Is feasible. However, a plurality of window applications that operate on a plurality of computers (including cases where they are different operating systems) cannot be displayed and used simultaneously without switching screens across a plurality of display devices.

  As a technique for sharing an input device such as a pointing device such as a keyboard and a mouse among a plurality of computers including different operating systems, Win2VNC (hereinafter referred to as known technique 5), Synergy (hereinafter referred to as known technique 6), etc. There is. When these technologies are used to physically arrange display devices connected to a plurality of computers including different operating systems, they can be operated with a set of input devices such as a keyboard and a mouse. Further, when the pointing device hits the right end of the display device, an operation of appearing at the left end of the other display device is possible.

JP 2007-164330 A

  An object of the present invention is to enable a plurality of computers to mutually display one window application across a plurality of display devices connected to a plurality of computers (including cases in which different operating systems are used) (hereinafter referred to as multicomputer multi-computer It is to provide a screen sharing system, a screen sharing method, and a screen sharing program.

  As a use environment of the present invention, a plurality of display devices (displays) physically arranged side by side, a plurality of computers (including cases where they are different operating systems) connected to them, and a single pointing device for operating them And an input device such as a keyboard. According to the present invention, a user can use a plurality of computers as one integrated display space (drawing space) by recognition using an environment (multi-display environment) in which a plurality of display devices are connected to one computer. . As a mechanism for this, the present invention is characterized by the following screen sharing method.

A display device connected to a plurality of computers is treated as one continuous coordinate space and drawing space, so that the root window of the computer that participates in the screen sharing system (the name of the image area displayed on the display device, also called the desktop) ) And coordinate information extracted from the image information of the window application (also called the top window with respect to the root window) using a determination algorithm. And a data structure for managing the coordinates where the image information is to be drawn, and its unique processing steps.

A program called a window manager or an X server is installed in the operating system of each computer. This program manages generation, deletion, drawing, and composition of window applications, and generates image data (also referred to as a frame buffer) of a root window to be displayed on the display device. In addition, this program writes in a memory area called an off-screen buffer for the purpose of synthesizing the window application image with the root window. In the present invention, at the time of writing to the off-screen buffer, a program called “screen sharing control unit” copies the off-screen buffer according to the purpose of screen sharing and transfers it to the “screen sharing control unit” of a different computer. It has a unique processing step of sending.

The “screen sharing control unit” of the computer that has received the copied off-screen buffer data works with a program called a window manager or X server to generate a window application for displaying the received partial image. Thus, it has a unique mechanism for performing state management such as image update and window application deletion in response to a request from the transmission source.

  In the present invention, the image data of the window application is copied and transmitted via the network at the timing when the image data of the window application is drawn in the off-screen buffer on the memory by the window manager that is higher in the virtual display driver. Thus, one window application is displayed across a plurality of display devices that are physically arranged and arranged respectively connected to a plurality of computers.

  When a window application overlaps an image drawing area of a display device connected to a different computer, the window manager copies the image data drawn in an off-screen buffer in the memory and transfers the image data to a different computer. The program that has received the image data instructs the window manager of the computer to generate a window for image display, and displays the image on the window. Image data is displayed across a plurality of display devices connected to different computers that are physically arranged. In addition, since the transferred image data is handled as one window by the remote desktop, it can be managed at one depth level (Z-Order). Further, since there can be a mask image for the image data transferred for each window, alpha blending display is also possible.

  The first effect is that a plurality of display devices arranged in a physical arrangement without switching the screen can be used across the screen as a single display device for the operation of a plurality of window applications operating on different computers.

  The reason for this is that the present invention treats display devices arranged in a physical array of different computer window applications as a continuous drawing space, and transfers drawing information to each other so that the window where the drawing area overlaps with other display devices is displayed. This is because it can be displayed.

  The second effect is that the operation of the window provided by the operating system on which the window application operates can be operated even between different operating systems.

  The reason is that the transferred drawing information is transferred as drawing information including the frame of the window and the buttons arranged in the frame, and the remote top window on the transferred side only displays the drawing information faithfully. Since it is a window, the design of the frame of the window does not change at the boundary line straddling the display device. For windows that use alpha blending, the same appearance can be reproduced if the destination supports alpha blending.

  The third effect is that it is efficient because it does not consume a large area of the network.

  The reason is that the drawing information of the entire screen is not transferred like the remote desktop, but only the drawing information of the portion where the drawing area overlaps with other display devices is transferred, so traffic does not occur if there is no overlapping portion. . Even when the overlapping portion is small, the amount of information to be transferred is small, so it is efficient because the global area of the network is not consumed.

It is a figure which shows the structure of the 1st Embodiment of this invention. It is a flowchart which shows the participation procedure to a screen sharing system. It is a figure which shows the management table 119. It is a figure which shows drawing of the display apparatus physically arrange | positioned of computers A and B. FIG. It is a figure which shows the example of the management table of computers A and B. FIG. It is a figure which shows drawing of the display apparatus physically arrange | positioned of computer A, B, C, D. FIG. It is a figure which shows the example of the management table of computer A, B, C, D. It is a figure which shows the determination method of the presence or absence of the overlap of a drawing area, and the transfer object area | region in that case. It is a figure which shows the acquisition flow of a transfer object area | region. It is the transmission processing flow regarding drawing of a screen sharing control part. It is a reception processing flow regarding drawing of a screen sharing control unit.

  Next, the configuration of the first exemplary embodiment of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1, in the first embodiment of the present invention, a computer A (central processing unit; processor; data processing device) 100 and a computer B (central processing unit; processor; data processing device) operating by program control are illustrated. 200, a display device 101 and an input device 116 connected to the computer A100, and a display device 201 and an input device 216 connected to the computer B200.

  Computer A 100 includes display driver 102, root window buffer 104, window manager 105, off-screen buffer 107, off-screen buffer 111 for remote top window 110 for computer B, off-screen buffer broker 112, An input device broker 113, a network interface 114, an input device driver 115, a virtual input device driver 117, a screen sharing control unit 118, and a management table 119 are provided. The window manager 105 manages the root window 103, the top window 106, and the remote top window 110 for the computer B. The off-screen buffer 107 stores drawing information a108 and drawing information b109. The off-screen buffer 111 stores drawing information c208.

  Computer B 200 includes display driver 202, root window buffer 204, window manager 205, off-screen buffer 207, off-screen buffer 211 for remote top window 210 for computer A, off-screen buffer broker 212, An input device broker 213, a network interface 214, an input device driver 215, a virtual input device driver 217, a screen sharing control unit 218, and a management table 219 are provided. The window manager 205 manages the root window 203, the top window 206, and the remote top window 210 for the computer A. The off-screen buffer 207 stores drawing information c208 and drawing information d209. The off-screen buffer 211 stores drawing information b109.

  The network interface 114 of the computer A100 and the network interface 214 of the computer B200 are connected by a network.

  Each of these means generally operates as follows. First, as an image output unit of the computer A100, the top window 106 operating on the computer A100 is newly generated or redrawn by calling a function of the window manager 105, and the drawing information is recorded in the off-screen buffer 107. . The off-screen buffer broker 112 divides the recorded drawing information into drawing information a108 displayed on the display device 101 of the computer A100 and drawing information b109 displayed on the display device 201 of the computer B200. The off-screen buffer broker 112 transfers the drawing information b109 to the off-screen buffer broker 212 of the computer B200 via the network interface 114 and the network interface 214. The off-screen buffer broker 112 instructs the window manager 105 to manage the drawing information c208 transferred from the computer B200. The window manager 105 holds the drawing information c208 in the off-screen buffer 111 in order to newly generate or redraw the remote top window 110. When displaying on the display device 101 of the computer A 100, the drawing information a 108 and the drawing information c 208 are written in the root window buffer 104 that manages the root window 103, and the drawing information is synthesized, and a drawing command to the display driver 102 is used. Drawing on the display device 101.

  As an input unit of the computer A100, the input device 116 holds an operation event from a pointing device such as a mouse or an operation event from a keyboard and transmits the operation event to the input device driver 115. Since the input device 116 is shared by the computer A100 and the computer B101, the input device broker 113 operates according to the coordinates of the pointing device.

  As network communication means of the computer A100, the drawing information b109 is transferred to the off-screen buffer 211 of the remote top window 210 of the computer B200, or the operation event of the input device driver 115 is transferred to the virtual input device driver 215 of the computer B200. To do. Network communication is performed using existing technology such as TCP / IP communication in the Local Area Network.

  Next, the operation of the first embodiment will be described in detail. First, FIG. 4 shows an image of an implementation result of the present invention. In an environment where the display device 101 is connected to the computer A and the display device 201 is connected to the computer B, an image of one application of the computer A is divided into the top window 106 and the remote top window 210, and the two display devices It is displayed to straddle. Further, an image of one application of the computer B is divided into a top window 206 and a remote top window 110 and displayed so as to straddle two display devices.

  Next, a root window management table 500 for managing information of computers participating in the screen sharing system of the present invention will be described with reference to FIG. The root window management table 500 includes a list of root window IDs belonging to the screen sharing system, information indicating which root window belongs to the local computer, and global coordinates of the root window. . The global coordinates of the root window match the physical arrangement of the added computer display device with the upper left coordinate of the root window of the first computer when configuring the screen sharing system as the origin (0, 0). The global coordinates of the root window of the added computer are set at a distance equal to or greater than the screen resolution of the display device. The physical layout is defined by a user who uses the screen sharing system.

Examples of root window management table of _{m 0} in FIG. 5 R500, as R501 is shown, _{when m 0} to the left, the user placement of the display device such as _{m 1} to the right defined, the resolution of all of the display device 1280 If it is × 1024, it becomes the global coordinates of the root window described in the third column of R500 and R501, respectively.

  Next, a procedure for participating in the screen sharing system when the computer A100 and the computer B200 constitute the screen sharing system will be described with reference to the flowchart of FIG. Here, a case where the user performs a procedure by operating the computer A100 will be described as an example. First, the screen sharing control unit 118 of the computer A100 inquires of the screen sharing control unit 218 of the computer B200 about the presence or absence of the root window management table 500 via the network interfaces 114 and 214, obtains the result, and obtains the result. The screen sharing control unit 118 checks whether or not the root window management table 500 is present (step S400). As a result, the process branches to four processing flows.

  As a first processing flow, when the root window management table 500 already exists in the computer A100, the record of the computer B200 is added to the root window management table 500 of the computer A100 (step S401). Next, the root window management table 500 of the computer A is copied to the computer B via the network interfaces 114 and 214 (step S402). If there is a record of another computer in the root window management table 500 of the computer A, the addition of the record of the computer B 200 is notified using the network interface 114 (step S403).

  As a second processing flow, when the root window management table 500 already exists in the computer B200, a record of the computer A100 is added to the root window management table 500 of the computer B200 (step S404). Next, the root window management table 500 of the computer B is copied to the computer A via the network interfaces 214 and 114 (step S405). If there is a record of another computer in the root window management table 500 of the computer B, the addition of the record of the computer A is notified using the network interface 214 (step S406).

  As a third processing flow, when the computer A 100 and the computer B 200 have the root window management table 500, the record information of the two root window management tables 500 is merged by communication between the screen sharing control units 118 and 218 (step S407). ). Next, the computer A100 notifies the merged result to the other computers registered in the root window management table 500 of the computer A100 and the computer B200 via the network interface (step S408).

  As a fourth processing flow, when neither the computer A 100 nor the computer B 200 has the root window management table 500, the screen sharing control units 118 and 218 newly create the root window management table 500, respectively, and the computer A 100 and the computer A A record of B200 is added (step S409).

  When the corresponding one of the four branched processing flows is completed, the screen sharing control unit 118 requests the user to specify a computer to be controlled by the input device 116 such as a pointing device such as a mouse or a keyboard (step S410). ). An arbitrary number of computers registered as records in the root window management table 500 can be designated, but here, the processing flow branches into three designated computers A100, B200, and other computers C, respectively. Will be described.

  First, when the computer A100 is designated as a control destination, a signal input from the input device 116 can be operated as it is by the input device driver 115. When there is an input from an input device other than the computer A, for example, the input device 216 of the computer B200, the input device driver 215 receives the input signal, but the input device broker 213 inputs it through the network interfaces 214 and 114. It is transferred to the device broker 113 and processed as an input from the virtual input device driver 117 of the computer A100 to the computer A100 (step S411).

  When the computer B is designated as the control destination as the second processing flow, the signal input from the input device 216 can directly operate the computer B200 by the input device driver 215. When there is an input from an input device other than the computer B, for example, the input device 116 of the computer A100, the input device driver 115 receives the input signal, but the input device broker 113 inputs it through the network interfaces 114 and 214. It is transferred to the device broker 213 and processed as an input from the virtual input device driver 217 of the computer B200 to the computer B200 (step S412).

  As a third processing flow, even when another computer C registered in the root window management table 500 is designated as a control destination, the computer C can be similarly operated by the input device of the computer C, and the input devices 116 and 216 can be operated. Is finally transferred to the virtual input device driver of the computer C, and the computer C can be operated (step S413). This completes participation in the screen sharing system.

Next, a table for managing the individual top window is a window application running on a computing m _i shown in FIG. 3, the top window management table 501 of m _i will be described. The top window management table 501 is composed of a top window ID, global coordinates of the top window, and a root window ID to which drawing information is transferred. As the top window ID, information that can be uniquely identified by information obtained by concatenating the root window ID and the window ID is used. Root window ID of the transfer destination of the drawing information, when overlapping the drawing area of the display device in which the top window is connected to a computer other than the m _i which operates on the m _i, column for recording the root window ID of the computer It is.

For example, when the top window m ₀ -ID1 is arranged on the two display devices like the global coordinates described in the second column as in the example R502 of the top window management table of m ₀ in FIG. The root window ID of the drawing information transfer destination as in the third column is specified in steps S713, S714, S715, S716, and S717 in FIG. 10, and is recorded in the third column of the top window management table (S718 in FIG. 10). Specifically, at S713, if the root window ID is _{m 1,} not a local machine (own computer), the process proceeds to S714, b (x) ≧ A (x) it is, 1399 ≧ 0 In S715, a (x) ≦ B (x) is true if 600 ≦ 1279. In S716, b (y) ≧ A (y) is true if 499 ≧ 0. In S717, a (y) ≦ B (y) becomes true at 600 ≦ 1023, the process proceeds to S718, the root window IDm ₁ is described in the record as a root window ID of the drawing information transfer destination.

Then, if m _i top window drawing information destination root window ID of the record of the management table 501 of the shown in FIG. 3 is present, the drawing of m _i which manages the transfer target region of the drawing information of the top window The information transfer target area management table 502 will be described. The drawing information transfer target area management table 502 is composed of records that are uniquely identified using a combination of the top window ID in the first column and the root window ID of the drawing information transfer destination in the second column as a key. As information managed by the key, data of p (x, y) and q (x, y), which are global coordinates of the drawing information transfer target area, is managed.

For example, a ₀₁ (x, y) and b ₀₁ (x, x, y) recorded in R502 from the information of the top window m ₀ -ID1 as in the example R504 of the drawing information transfer target area management table of m ₀ in FIG. The data of y) is acquired, the data of A ₁ (x, y), B ₁ (x, y) recorded in R500 is acquired from the information of the root window ID m ₁ of the drawing information transfer destination, and S600 in FIG. To S611, p (x, y) and q (x, y) data are acquired and recorded as records in the management table R504. Specifically, in S600 of FIG. 9, a ₀₁ (x) <A ₁ (x) is true when 600 <1280, and p (x) = 1280 in S601. In S603, a ₀₁ (y) <A ₁ (y) becomes false when 100> 0, and p (y) = 100 in S605. In S606, b ₀₁ (x) <B ₁ (x) is true when 1399 <2599, and in S607, q (x) = 1399. In S609, b ₀₁ (y) <B ₁ (y) becomes true when 499 <1023, and q (y) = 499 in S610. Note that the processing of FIG. 9 extracts the transfer target area in accordance with the classification of the overlapping method according to the size relationship between the global coordinates of the root window and the global coordinates of the top window shown in FIG. This is a flow of the process of substituting for (x, y).

Next, a process flow (transmission process) related to drawing by the screen sharing control unit illustrated in FIG. 10 will be described. Screen sharing control unit of the shared screen computer participating in the system (118 or 218 in FIG. 1) is the window manager from the individual top window is a window application running on a computing m _i (105 and 205 in FIG. 1) Four events to be sent (top window redrawing S700, top window creation and drawing S708, top window resizing and drawing S710, top window disappearance S722) are defined as a window application by function wrapper processing, call function override, etc. It enters the window manager process and starts when the event occurs.

First, when the event of top window generation and drawing S708 occurs, the top window ID is generated, the off-screen buffer is generated, and the drawing information of the window application is stored (S709). And sets a counter i of the root window to 0 in S712, in S713, with reference to the root window management table 500 of the _{m i} shown in FIG. 3, the root window ID is a local computer record is _{m i} If the data of the column is confirmed and the machine is the own machine (when the data is ◯), the result of S713 is set as false, i is counted up, and S713 is determined again. (Although omitted from the flow chart, if i exceeds the maximum value of i and there is no corresponding record in the root window management table, the flow process ends with no drawing target area.) If it is confirmed that the machine is not its own machine (when the data is-), the result of S713 is set as true, the comparison from S714 to S717 is performed, and if all are true, S718 is performed, and even one of them is false. if, it is determined that there is no drawing transfer object region to the root window _{m i,} not a resize event in the determination of S726, the process moves to decision of S721, increments the _{i, m i>} m _max flow when (if m _i does not exist) of the ends, if m _i is present, route window of i which is counted up from S713 It performs a process for m _i. In S718, the _{m i} recorded already root window ID of drawing information transfer destination top window management table of _{m i} as described (501 in FIG. 3), the global coordinates p in the transfer object region of FIG. 9 at S719 acquires q, is recorded in the management table of rendering information transferred area of _{m i} (502 in FIG. 3). Next, in S720, the coordinate values of p and q of the drawing target area are obtained from the management table, and the global coordinate values of p and q are generated in S709 and S711 from the global coordinate values of a _ij in the top window. drawing information (RGB information includes mask information of alpha blending, if necessary) in the region indicated by converting the local coordinates on the screen buffer and transmits to the screen sharing control unit of m _i with top window ID to get . The i is counted up by _S721, m _{i> m} flow when _{(if m i} is not present) of _max ends, _{if m i} is present, the root window _{m i} for i which is counted up from S713 Process.

When the event of the top window resizing and drawing S710 occurs, the ID of the top window is acquired in S711, an off-screen buffer is generated, and the drawing information of the window application is stored. As in the case of the generation of the top window and the event of drawing S708, it is determined whether there is a drawing transfer target area by the determination of S713 to S717. If there is a drawing transfer object region records the m _i in the management table 501 in the root window ID of drawing information transfer destination as already described. However, it does not do anything if the root window IDm _i already drawing information transfer destination for the resizing process is present in the record row. Get the transfer object region at S719, described in the management table 502 of the drawing information transfer object region of the _{m i.} However, if there is already a global coordinate record line in the drawing information transfer target area for resizing processing, the coordinate data of p (x), p (y), q (x), and q (y) is updated. S720 and S721 are processed in exactly the same manner as the top window generation and drawing S708. In the process of S717 from S714, when there is judged false, since there is no drawing transfer object region, if during the processing of drawing and resizing of top window at S726, at S727, the remote computer _{m i} The top window ID being processed in the top window management table 501 is checked to see if the information on the drawing target area is in the list. If so, together with the window ID of the deletion request of the remote top window area at S728, and transmits the _{m i.} In step S729, the record line related to the top window ID and the root window ID of the drawing information transfer destination is deleted from 502, and the drawing information transfer destination of the third column related to the top window ID is deleted from the top window management table 501. The data of the root window ID corresponding to the root window ID is deleted. The subsequent S721 is the same as the case where the top window generation and the drawing S708 occur.

When the event of the disappearance of the top window S722 occurs, the ID of the top window that disappears is acquired in S723. And sets a counter i of the root window to 0 in S724, in S725, with reference to the root window management table 500 of the _{m i} shown in FIG. 3, the root window ID is a local computer record is _{m i} If the data of the column is confirmed and the machine is the own machine (when the data is ◯), the result of S725 is set as false, i is counted up, and S725 is determined again. (Although omitted from the flow chart, if i exceeds the maximum value of i and there is no corresponding record in the root window management table, the flow process ends with no drawing target area.) If it is confirmed that the machine is not its own machine (if the data is-), the result of S725 is true. Already it performs processing the S727, S728, S729 described at S721, and counts up _i, flow in the case of _{m i>} m _{max (if m i} is not present) is terminated, _{if m i} is present performs processing for root window _{m i} of i which is incremented from S725.

When the top window redrawing S700 event occurs, the ID of the top window to be redrawn is acquired in S701, an off-screen buffer is generated, and the drawing information of the window application is stored. And sets a counter i of the root window to 0 in S702, in S703, with reference to the root window management table 500 of the _{m i} shown in FIG. 3, the root window ID is a local computer record is _{m i} If the data of the column is confirmed and the machine is the own machine (when the data is ◯), the result of S703 is set to be false, i is counted up, and S703 is determined again. (Although omitted from the flow chart, if i exceeds the maximum value of i and there is no corresponding record in the root window management table, the flow process ends with no drawing target area.) If it is confirmed that the machine is not its own machine (if the data is-), the result of S703 is true. At S704, information of the object area to a remote computer m _i is checked for top window ID in the processing of top window management table 501 whether the list. If there is, in step S705, the coordinate values of p and q of the drawing target area are obtained from the management table, and the global coordinate values of p and q are generated in step S701 from the global coordinate values of a _ij in the top window. Drawing information (RGB information, including alpha blending mask information as necessary) of the area indicated by being converted into local coordinates on the buffer is acquired. At S706, the drawing information of the drawing target region, together with the window ID, and transmits the _{m i.} The i is counted up by _S707, m _{i> m} flow when _{(if m i} does not exist) of _max ends, _{if m i} is present, the root window _{m i} of i which is counted up from S703 Process.

Next, a processing flow (reception processing) related to drawing by the screen sharing control unit illustrated in FIG. 11 will be described. The screen sharing control unit (118 or 218 in FIG. 1) of the computer participating in the shared screen system generates, deletes, resizes, and redraws the remote top window by the process shown in FIG. 10 from the computer having _mi as the root window. Send the request. The computer that has received the request and has _mk as the root window manages the remote top window in the management table 503 of the drawing target area of the remote top window in FIG.

When the top window ID (m _i -ID _j ) and the drawing information are received (S900), in S901, a record that matches m _i -ID _j in the first column of the top window drawing target area management table 503 Check if exists. If it exists, it is checked in step S902 whether the received data has p and q coordinate values. If there are coordinate values of p and q, it can be understood that the request is for resizing and redrawing of the remote top window. Therefore, in S903, the coordinate values of p and q of the record in the management table 503 of the drawing target area of the remote top window are determined. Update. In step S904, the top window ID (ID _n ) of m _k recorded in the record that matches m _i -ID _j is designated, and the received drawing information (RGB information, alpha blending mask as necessary) Information) instructs the window manager to resize and redraw the remote top window to complete the processing flow. P at S902, if there is no coordinate value of q, since it can be seen that a request for re-drawing of the remote top window, at _S905, the top of the _{m k} which is recorded in the record that matches the m i -ID _j A window ID (ID _n ) is designated, and the window manager is instructed to redraw the remote top window with the received drawing information (RGB information, alpha blending mask information as necessary) to complete the processing flow. If it is determined in S901 that there is no record that matches m _i -ID _j , it can be determined that the request is for generating a remote top window. In S906, the management table 503 for the drawing target area of the remote top window is determined. In step S907, the window manager is instructed to generate a remote top window using the received p and q coordinate values and drawing information. Then, the top window ID (ID _n ) of m _k generated in S908 is acquired from the window manager, recorded in the record, and the processing flow is completed.

On the other hand, when the remote top window deletion request is received together with the top window ID (m _i -ID _j ) (S909), the top window ID (ID _n ) is designated in S910 to delete the remote top window from the window manager. To order. In step S911, the record line matching the top window ID (m _i -ID _j ) is deleted from the drawing target area management table 503 of the remote top window, and the processing flow is completed.

  Next, effects of the first exemplary embodiment of the present invention will be described. In the first embodiment of the present invention, the screen sharing control unit is installed in a computer that participates in the screen sharing system and can share global coordinates, so that it overlaps the image drawing area of a display device connected to a different computer. In some cases, the image data drawn in the off-screen buffer can be copied and transferred to a different computer.

  Further, in the first embodiment of the present invention, in addition to the RGB drawing information to be transmitted, an alpha blending mask image is transmitted, so that the top window image and the remote top window image using alpha blending are combined. Is possible.

  Further, in the first embodiment of the present invention, since the transferred image data is handled as one window in the remote desktop, the redrawn flag is included in the transmission data by selecting the window with the mouse. Management is possible at one depth level (Z-Order).

Another embodiment of the present invention is shown in FIGS. 6 and 7 illustrates the display image of the top window on the display device when placed side by side four display apparatus physically, the example of the management table of the computer that has the root window m _0.

  INDUSTRIAL APPLICABILITY According to the present invention, the present invention can be applied to applications such as integrated management of window applications that operate on a plurality of computer servers and an integrated monitoring apparatus. Further, the present invention can be applied to an application such as an alternative function of a remote desktop function or an alternative function of a dual display function of a user who owns a plurality of computers.

100 Computer A
200 Computer B
102, 202 Display driver 104, 204 Root window buffer 105, 205 Window manager 107, 207, 111, 211 Off-screen buffer 112, 212 Off-screen buffer broker 113, 213 Input device broker 114, 214 Network interface 115, 215 Input device driver 117, 217 Virtual input device driver 118, 218 Screen sharing control unit 119, 219 Management table 103, 203 Root window 106, 206 Top window 110, 210 Remote top window 108 Drawing information a
109 Drawing information b
208 Drawing information c
209 Drawing information d

Claims (3)

In a screen sharing system in which multiple pairs of display devices and computers are connected via a network,
Each computer
A root window management table for managing coordinate information of a root window displayed on a display device paired with each computer;
A top window management table for managing coordinate information of a top window displayed over a plurality of root windows displayed on a plurality of display devices;
A screen sharing control unit,
The screen sharing control unit of one computer draws a portion of the top window to be displayed by this computer other than the area displayed on the root window displayed on the display device paired with this computer. Send information and coordinate information to the screen sharing control unit of other computers,
When the screen sharing control unit of the other computer receives the drawing information and coordinate information of the part other than the area, this part is displayed on the root window displayed on the display device paired with the other computer. A screen sharing system characterized by being displayed on the screen. In a method for a plurality of computers sharing a screen in a state where a plurality of sets of display devices and computers are connected via a network,
Each computer
Manage the coordinate information of the root window displayed on the display device paired with each computer,
Manage the coordinate information of the top window displayed across multiple root windows displayed on multiple display devices,
One computer displays drawing information and coordinate information of a portion other than an area displayed on a root window displayed on a display device paired with the computer among top windows to be displayed by the computer. Send to other computers,
When the other computer receives the drawing information and the coordinate information of the part other than the area, the other computer displays the part on the root window displayed on the display device paired with the other computer. A featured screen sharing method. In a program for a plurality of computers sharing a screen in a state where a plurality of sets of display devices and computers are connected via a network,
Each computer managing coordinate information of a root window displayed on a display device paired with each computer;
Each computer managing coordinate information of a top window displayed across a plurality of root windows displayed on a plurality of display devices; and
One computer displays drawing information and coordinate information of a portion other than an area displayed on a root window displayed on a display device paired with the computer among top windows to be displayed by the computer. Sending to other computers,
When the other computer receives drawing information and coordinate information of a part other than the area, displaying the part on a root window displayed on a display device paired with the other computer; A screen sharing program that causes each computer to execute.

Images