Computer graphics processing and selective visual display system – Computer graphics processing – Three-dimension
Reexamination Certificate
2000-11-27
2002-09-17
Zimmerman, Mark (Department: 2671)
Computer graphics processing and selective visual display system
Computer graphics processing
Three-dimension
C345S519000, C345S611000
Reexamination Certificate
active
06452595
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to antialiasing and, more particularly, to graphics pipeline systems with antialiasing capabilities.
BACKGROUND OF THE INVENTION
A general system that implements a graphics pipeline system is illustrated in Prior Art FIG.
1
. In this system, data source
10
generates a stream of expanded vertices defining primitives. These vertices are passed one at a time, through pipelined graphic system
12
via vertex memory
13
for storage purposes. Once the expanded vertices are received from the vertex memory
13
into the pipelined graphic system
12
, the vertices are transformed and lit by a transformation module
14
and a lighting module
16
, respectively, and further clipped and set-up for rendering by a rasterizer
18
, thus generating rendered primitives that are displayed on display device
20
.
During operation, the transform module
14
may be used to perform scaling, rotation, and projection of a set of three dimensional vertices from their local or model coordinates to the two dimensional window that will be used to display the rendered object. The lighting module
16
sets the color and appearance of a vertex based on various lighting schemes, light locations, ambient light levels, materials, and so forth. The rasterization module
18
rasterizes or renders vertices that have previously been transformed and/or lit. The rasterization module
18
renders the object to a rendering target which can be a display device or intermediate hardware or software structure that in turn moves the rendered data to a display device.
Antialiasing is a method for improving the realism of an image by removing jagged edges during rendering. Such jagged edges appear because a computer monitor has discrete pixels, that cannot adequately display image features that are finer than pixel resolution.
FIG. 1A-1
illustrates an image
10
that is subject to aliasing.
If one puts a grid over the image
10
of
FIG. 1A-1
and only colors those squares that are entirely within the circle, aliasing occurs.
FIG. 1A-2
illustrates the image
10
of
FIG. 1A-1
subject to aliasing
12
. The “blockiness” that is shown is the result of aliasing, and is exactly what happens when you try to display a circle on a computer screen.
FIG. 1A-3
illustrates the manner in which aliasing may be assuaged somewhat by using a finer grid
14
. Still, the problem is not completely alleviated with the finer grid
14
, and more expensive hardware is necessary to increase the resolution of the computer screen to accommodate the finer grid
14
.
Because of the digital nature of computers, it is not possible to completely eliminate aliasing. However, it is possible to minimize its effects. One solution involves treating each pixel as a finite square area, rather than as a mere point on the screen. Either by computing the color at many points within a pixel, or by keeping track of multiple primitives' partial coverage overlapping a pixel, the final pixel color can be a weighted average of all relevant portions. By capturing information from many points within a pixel, details too fine to be expressed by one-per-pixel sampling make an appropriate contribution.
Continuing with the image
10
of
FIGS. 1A-1
though
1
A-
3
, the antialiased circle might then be represented with reference to
FIG. 1A-4
.
FIG. 1A-4
illustrates the manner in which antialiasing
16
helps eliminate jagged edges, thus making an image seem more realistic.
FIG. 1B-1
illustrates a non-integrated prior art graphics system implementation that does not employ any antialiasing process. As shown, an off-chip process module
20
(i.e. rasterizer) has a first dedicated memory
22
. In use, the off-chip process module
20
feeds a pixel fragment processor
24
, having its own second dedicated memory
26
. Without any aliasing preventive measures, the off-chip process module
20
and the pixel fragment processor
24
both communicate data to and from their respective memories at a similar rate in a parallel manner.
FIG. 1B-2
illustrates a non-integrated prior art graphics system implementation that employs an antialiasing process. In operation, the pixel fragment processor must access graphics data in the second dedicated memory
26
at an accelerated rate (i.e. ×4) to accommodate antialiasing sampling requirements. This bottleneck slows down computer graphics processing, and further leaves the first dedicated memory
22
idle three out of four clock cycles.
FIG. 1B-3
illustrates a non-integrated prior art graphics system implementation that employs an antialiasing process. Since the implementation is not integrated, additional post-filtering logic
30
must be employed to execute any postfiltering routines after the rasterizer has rendered the image. This detrimentally affects cost since much of the logic is redundant with respect to that of the off-chip process module
20
.
Thus, the incorporation of antialiasing in a non-integrated graphics system implementation suffers from a lack of efficient utilization of memory bandwidth (See FIG.
1
B-
2
), and further requires expensive additional logic (See FIG.
1
B-
3
).
Generally, integration is often limited by the cost of implementing and manufacturing multiple processing modules on a single chip. In the realm of graphics processing, attempts to integrate modules to increase speed can make costs prohibitive, since the cost of an integrated circuit increases rapidly as die size increases. High performance transform and lighting engines alone require significant area and are thus expensive to implement on-chip. Additional on-chip logic for additional functionality compounds the size and can raise the die cost to prohibitive levels.
There is therefore a need for a cost-effective computer graphics pipeline integration which overcomes the shortcomings inherent to antialiasing on a non-integrated platform.
DISCLOSURE OF THE INVENTION
A graphics pipeline system is provided for graphics processing. Such system includes a transform module adapted for receiving vertex data. The transform module serves to transform the vertex data from a first space to a second space. Coupled to the transform module is a lighting module which is positioned on the single semiconductor platform for performing lighting operations on the vertex data received from the transform module. Also included is a rasterizer coupled to the lighting module and positioned on the single semiconductor platform for rendering the vertex data received from the lighting module. During use, an antialiasing feature is implemented to improve a quality of the graphics rendering.
Such integration overcomes many of the shortcomings associated with non-integrated systems incorporating antialiasing features. To this end, applications can thus take advantage of such improvements by invoking the antialiasing feature associated with the single semiconductor platform via a standard interface.
These and other advantages of the present invention will become apparent upon reading the following detailed description and studying the various figures of the drawings.
REFERENCES:
patent: 5694143 (1997-12-01), Fielder et al.
patent: 5838377 (1998-11-01), Kimura et al.
patent: 5977997 (1999-11-01), Vainsencher
patent: 6000027 (1999-12-01), Pawate et al.
patent: 6104417 (2000-08-01), Nielsen et al.
patent: 6198488 (2001-03-01), Lindholm et al.
patent: 6326964 (2001-12-01), Snyder et al.
patent: 0690430 (1996-01-01), None
patent: 0690430 (1996-07-01), None
patent: 98/28695 (1998-07-01), None
patent: 99/52040 (1999-10-01), None
Marc Olano and Trey Greer, “Triangle Scan Conversion using 2D Homogeneous Coordinates” 1997 Siggraph/Eurographics Workshop.
Molnar Steven E.
Montrym John S.
Voorhies Douglas A.
Nvidia Corporation
Silicon Valley IP Group, LLC.
Stevenson Philip H.
Zilka Kevin J.
Zimmerman Mark
LandOfFree
Integrated graphics processing unit with antialiasing does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Integrated graphics processing unit with antialiasing, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Integrated graphics processing unit with antialiasing will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2840499