Antialiasing Image Patterns For GeForce3

Running today contents +50% faster than GeForce2 Ultra under antialiasing modes is the shining point that GeForce3 bring to consumers at present. They are just the firenew antialiasing mechanism and memory bandwidth interface that make GeForce3 shine. In this page, the antialiasing image patterns and memory bandwidth interface are explained through diagrams.

Here is the NVIDIA description of generic solutions for antialiasing of images on PC. "Algorithmic antialiasing techniques involve "sampling" the content of each pixel at multiple locations, meaning that the color is computed at more than one location inside the area covered by the pixel. The results from these "samples" are combined to determine the final color of the pixel. These samples are essentially additional pixels, used to increase the effective resolution of the image to be displayed. If the edge of an object falls partially inside the area of pixel, its color and the color of another object that partially fills the "area" of the pixel can both be used to calculate the final color. The result is smoother transitions from one line of pixels to another line of pixels along the edges of objects, where aliasing is most obvious."

GeForce3 has three antialiasing modes. From the theory simulating results of the antialiasing image patterns for GeForce3 showed in Table 1, it could be found that "4x AA" has the best antialiasing image quality, while "Quincunx AA" has better antialiasing image quality than "2x AA". Comparing with the antialiasing screenshots that have been posted on Tomshardware, Rivastation and Hardocp by further magnifying, the patterns in Table 1 come close the real ones considerably.

Table 2 shows the efficiency of GeForce3 memory bandwidth interface that is extremely in favor of antialiasing fulfillment.

GeForce3 Lightspeed Memory Architecture	Illustration	GeForce3 / GeForce2 Memory Bandwidth Efficiency
Crossbar Memory Controller ( Memory controller that is optimized for accessing data with a fine granularity access pattern, ensuring that less fractions of the memory bandwidth is wasted when accessing small datasets. )		1 : 1
		4 : 1
Lossless Z Compression ( 4:1 lossless data compresses and decompresses by video chip hardware in real time, thus the memory bandwidth consumed by Z-buffer traffic is reduced by a factor of four. )		4 : 1
Z-Occlusion Culling ( A hidden surface removal (HSR) rendering mechanism that reduces memory bandwidth requirements by avoiding having to access pixels that would not be visible. )	it can demonstrate as much as four times the performance of traditional rendering mechanism, while in practice the typical benefit of it averages a 50%-100% improvement.	( 2 ~ 4 ) : 1