Display screen subsection rendering apparatus and method

• US 8,907,958 B2
• Filed: 08/11/2005
• Issued: 12/09/2014
• Est. Priority Date: 08/12/2004
• Status: Active Grant

• Current Assignee: ATI Technologies ULC (Advanced Micro Devices, Inc.)
• Original Assignee: ATI Technologies ULC (Advanced Micro Devices, Inc.)
• Inventors: Taylor, Ralph Clayton, Carey, John
• Primary Examiner(s): Hoang, Phi
• Application Number:
  US11/161,660
• Publication Number:
  US 20060055701A1
• Time in Patent Office: 3,407 Days
• Field of Search: 345/503, 345/522, 345/419, 345/422, 382/233
• US Class Current: 345/522
• CPC Class Codes: G06T 1/60 Memory management
• CPC Class Codes: G06T 15/005 General purpose rendering architectures

Abstract

A method and apparatus for providing rendering of subsections of screen space receives render commands associated with different screen subsections, such as from a command buffer populated by a coprocessor, and determines which screen section is currently being rendered by a rendering engine, or stated another way, which screen section the host processor wishes to have rendered, and evaluates screen subsection data that is associated with a received rendering command. The screen subsection data identifies a screen subsection for which the command refers. The method includes executing the command if it is determined that the command refers to a current screen section being rendered.

Claims

1. A method for providing rendering of subsections of a screen space comprising:

storing received screen subsection display mask data in memory identifying a screen subsection that is to be rendered;

fetching a group of stored rendering commands and associated object screen subsection rendering mask data from a command buffer, wherein at least a plurality of the fetched rendering commands indicate that they are predicated rendering commands;

storing the object screen subsection render command mask data associated with a given object in memory, the object screen subsection render command mask data indicating which screen subsections that the object is displayed in the plurality of subsections; and

discarding those fetched rendering commands whose associated object screen subsection render command mask data does not correspond to the screen subsection identified by the stored screen subsection display mask data, wherein the discarding comprises determining, on a per command basis, whether predicated rendering identification information in the command indicates that the command is a predicated rendering command and if so, then checking the command against the screen subsection display mask data.

2. The method of claim 1 wherein the received object screen subsection render command mask data is received from a first processor and wherein discarding those fetched commands whose associated object screen subsection render command mask data, is performed by a second processor.

3. A graphics processor comprising:

a rendering engine operative to render objects for multiple screen subsections;

a command processor, operatively coupled to the rendering engine, the command processor comprising;

screen subsection command discard logic operative to obtain received object screen subsection render command mask data associated with a given object and received screen subsection display mask data, the object screen subsection render command mask data indicating which screen subsections that the object is displayed in the plurality of subsections, the screen subsection display mask data identifying one of the multiple screen subsections that is to be rendered, and operative to discard fetched commands whose associated object screen subsection render command mask data does not correspond to the screen subsection identified by the screen subsection display mask data, wherein at least a plurality of the fetched commands indicate that they are predicated rendering commands, and wherein the screen subsection command discard logic is operative to determine, on a per command basis, whether predicated rendering identification information in the command indicates that the command is a predicated rendering command and if so, then check the command against the screen subsection display mask data in order to discard the fetched commands whose associated object screen subsection render command mask data does not correspond to the screen subsection identified by the screen subsection display mask data; and

wherein the rendering engine renders objects based on fetched commands that are not discarded.

4. Apparatus for providing rendering of subsections of a screen space comprising:

a first processor;

a display device operative to display display information;

a second processor, operatively coupled to the display device and operatively coupled to the first processor;

wherein the first processor is operative to provide rendering commands associated with different screen subsections and to store rendering commands and associated object screen subsection render command mask data in a command buffer, wherein at least a plurality of the rendering commands indicate that they are predicated rendering commands; and

wherein the second processor is operative to render objects for multiple screen subsections based on the object screen subsection render command mask data, the object screen subsection render command mask data indicating which screen subsections that the objects are displayed in the multiple screen subsections, and to store received screen subsection display mask data in memory, the screen subsection display mask data identifying one of the multiple screen subsections that is to be rendered;

fetch a group of stored rendering commands and associated object screen subsection render command mask data from a command buffer;

store received object screen subsection render command mask data in memory; and

discard those fetched commands whose associated object screen subsection render command mask data does not correspond to the screen subsection identified by the stored screen subsection display mask data, wherein the second processor is operative to determine, on a per command basis, whether predicated rendering identification information in the command indicates that the command is a predicated rendering command and if so, then check the command against the screen subjection display mask data in order to discard those fetched commands whose associated object screen subsection render command mask data does not correspond to the screen subsection identified by the stored screen subsection display mask data.

5. An apparatus that renders a screen space comprising:

a processor operative to evaluate screen subsection data associated with a received rendering command that identifies a screen subsection from a plurality of screen subsections for which the received rendering command refers to determine whether to execute the received rendering command,

execute the received rendering command if the received rendering command is associated with an object to be displayed in a current screen subsection being rendered, wherein screen subsection display mask data indicates the current screen subsection being rendered, and

populate a command buffer with rendering commands for the plurality of screen subsections wherein at least a plurality of the populated commands indicate that they are predicated rendering commands, wherein the processor is operative to determine, on a per command basis, whether predicated rendering identification information in the command indicates that the command is a predicated rendering command and if so, then check the command against the screen subsection display mask data.

6. In a system that renders a screen space, a method comprising:

evaluating, by a graphics processor that renders a plurality of screen subsections, screen subsection data that identifies a screen subsection for which one or more received rendering commands refer to determine whether to execute or discard the one or more received rendering commands;

executing, by the graphics processor, the one or more received rendering commands if the one or more received rendering commands correspond to an object to be displayed in a current screen subsection being rendered otherwise discarding the one or more rendering commands; and

populating a command buffer with rendering commands for a plurality of different screen subsections wherein at least a plurality of the populated commands indicate that they are predicated rendering commands wherein evaluating comprises determining, on a per command basis, whether predicated rendering identification information in the command indicates that a command is a predicated rendering command and if so, then checking the command against the screen subsection data.