Multi-screen synthesizing display apparatus and method

Abstract

A multi-screen synthesizing apparatus and method have been disclosed by the present invention. Display data of windows required to be displayed on the display terminal are mapped onto at least one logical screen by storing data in a video memory. Each of the windows is correlated with a set of window registers, and the location coordinates of the window and the identification of the corresponding logical screen are stored into the window register set when displaying the windows, the window register set having the highest priority level are found out, based on the location coordinates of the current scanning pixel, as the selected window register. The display data corresponding to the current pixel are read out from the logical screen corresponding to the selected window register and output to the display terminal. According to the present invention, the display data are not necessary to be written repeatedly during the switching operations of windows, thus the overhead for the CPU to process the display task can be reduced without increasing the occupied bandwidth. Thereby the display efficiency of various electronic devices having display ability can be improved and the display cost can be reduced.

Description

DESCRIPTION OF FIGURES

FIG. 1 is a diagram showing a display system in the prior art;

FIG. 2 is a block diagram showing a multi-screen display system according to the present invention;

FIG. 3 is a schematic diagram showing the superposition of multi-level windows of the present invention;

FIG. 4 is a schematic diagram showing the switching of the multi-level windows of the present invention; and

FIG. 5 is a flowchart showing the synthesis of the logical screens according to the present invention.

Claims

1. A multi-screen synthesizing display apparatus, comprising: a video memory comprising a plurality of logical blocks, each of which, as a logical screen, corresponds to a display terminal;a logical screen module for mapping display data of windows required to be displayed on the display terminal onto at least one of the logical screens;multiple sets of window registers assigned with priority levels, which, based their priority levels, corresponds to the windows to be displayed on the display terminal respectively, and each set of the window registers stores location coordinates of its corresponding window and an identification of the corresponding mapped logical screen;a logical screen synthesizing module for retrieving and outputting the display data which is contained in a logical screen indicated by an active set among the sets of window registers with highest priority level, based on the position coordinates of current scanned pixel.

2. The multi-screen synthesizing display apparatus of claim 1, further comprising a display driving module for receiving the display data from the synthesizing module and mapping the display data to the current scanning pixel in the display terminal.

3. The multi-screen synthesizing display apparatus of claim 2, wherein said window register set is provided with an Enable bit for activating ad deactivating the corresponding window.

4. The multi-screen synthesizing display apparatus of claim 3, wherein the synthesizing module finds out active window register sets containing the position coordinates of the current pixel as candidates; and then selecting one set of window register with highest priority among the candidates as a hit register set, reading out the display data corresponding to the current pixel, out of the logical screen indicated by the hit register set, as the data to be displayed on the display terminal.

5. The multi-screen synthesizing display apparatus of claim 3, wherein the synthesizing module finds out and lists all the active window register sets in the order of priority level, selectin one active register set having highest priority level and containing the position coordinates of the current pixel as a hit register set, reading the display data corresponding to the cu ent pixel, out of the logical screen indicated by the hit register set, as the data to be displayed on the display terminal.

6. The multi-screen synthesizing display apparatus according to claim 3, wherein said mapping module: mapping the windows overlapped each other onto dirt logical screens respectively; and mapping the windows not overlapped each other onto a same logical screen or different logical screens respectively.

7. The multi-screen synthesizing display apparatus according to claim 3, wherein the display of the current window is switched by setting the priorities of individual window register sets and changing the correspondence to the window registers, of the window to be switched.

8. A multi-screen synthesizing display method, comprising a window mapping step and a window synthesizing step, wherein said window mapping step comprises the following steps:A), mapping display data of windows to be displayed on a display terminal onto at least one logical screen, and stow each of the at least one logical screen into the video memory as a logical block; andB), correlating multiple sets of window registers with respective windows to be displayed on the display terminal according to priority levels of the sets of window registers, and storing location coordinates of the windows and an identifications of its corresponding logical screens into the correlated window register sets respectively; andsaid window synthesizing step comprises the following steps:C), receiving the location coordinates of a current scanning pixel;D), selecting and outputting the display data which is contained in a logical screen indicated by an active window register set with highest priority level, based on the position coordinates of a current scanned pixel.

9. The multi-screen synthesize display method of claim 8, wherein said window register set is provided with an Enable bit for activating and deactivating the corresponding window.

10. The multi-screen synthesizing display method of claim 9, wherein the step D comprising: E). finding out all the active window register sets containing the position cools of the current pixel as candidates;F. selecting the window register set with highest priority among the candidates as a hit register set;G. a reading the display data corresponding to the current pixel, out of tow logical screen indicated by the hit register set, as the data to be displayed on the display terminal.

11. The multi-screen synthesizing display method of claim 9, wherein the step A) comprising: mapping the windows overlap each other onto different logical screens respectively; and mapping the windows not overlapping each other onto a same logical screen or different logical screens respectively.

12. The multi-screen synthesizing display method according to claim 9, further comprising the following steps: predetermining the priority level for each set of window registers; andcorrelating a window which overlaps other windows to a set of window register with higher priority level and correlating an overlapped window to a set of widow register with lower priority level.

13. The multi-screen synthesizing display method according to claim 12, wherein if position coordinates of the current scanning pixel is not contained in any of the active windows, then the display data corresponding to the cut pixel are read from a logical screen corresponding to the background display, and outputted to the display terminal.