FAR CRY ANISOTROPIC FILTERING IMAGE QUALITY
ANALYSIS
Before we get started, please understand the following:
Image quality (IQ) is a very subjective thing
to compare (most of the time). Understanding this, I looked for only the most
noticeable differences. So, it's not to say that the screen shots below
contain only the differences I point out.
I used the Far Cry console commands
\save_game [name]
and the \load_game [name]
which allow for a 100% exact comparison screen shot regarding angle and
placement. There are variables such as moving grass, water, etc so I avoided
any differences that may have been affected by those factors. Even the angle
at which your player is looking is saved, so there is no discrepancy of the
sort in these comparisons.
I did not compare two different AF settings
for the same card. This is a comparison between the same (or different) AF
settings of one card against the other.
At the end of this section I will provide a zip
file for you of all the screenshots I took from FRAPS in their original BMP
format. Look for this in a few days if interested. There are more shots there than are shown here as well as all modes
(0xAF, 4xAF, 8xAF and 16xAF).
This is strictly an IQ comparison, performance
is not taken into consideration here.
There are many variables at play regarding
anisotropic filtering so each set of examinations below will vary somewhat.
I first looked for any cases where 4x on one card was better than 16x on the
other. In other cases I only found worthy differences at 16x for both cards.
Another examination has both of these cases included.
I used ATI's
The
Compressonator as a means of comparing the screenshots with settings
of 400% zoom and 400% difference brightened.
Areas outlined in red
indicate where ATI was better and areas outlined in
green indicate where NVIDIA was better. Letters ("A", "B",
etc) are used in some cases next to outlines for clarification. Note that I
outlined in the middle comparison window so as not to obscure the actual
screenshots.
Clicking on the thumbnails below will load a
1600x1200 PNG image 300KB~350KB in size
The first image below illustrates
that NVIDIA's 4x renders the fallen light pole's shadow considerably better (I'd
venture to say more completely actually) than does ATI's 16x. This is an
isolated area though as we see that ATI was better at rendering the dirt in
another isolated area.
The second image below is the
inverse of the one above in that we're comparing NVIDIA's 16x to ATI's 16x. The
reason for this is to illustrate that while NVIDIA's 4x was better than ATI's
16x in the example above, the same cannot be said for ATI's 4x.
Far Cry - Dock Wood Grain and Rock Face
Clicking on the thumbnails below will load a
1600x1200 PNG image 300KB~350KB in size
The first image below again
illustrates that NVIDIA's 4x mode is better that ATI's 16x mode in this isolated
area. This time it involves a more direct POV surface (the rock face "A"
outline) and not a horizontal one as was the case with the fallen light pole.
"B" is another area that just appeared cleaner than ATI in this case. ATI is
much cleaner in its highlighted area which is expected due to the angle and that
ATI is at 16x and NVIDIA is at 4x.
The last image below still shows the NVIDIA to be better at that flat rock
surface as well as expectedly improving on the dock surface area. ATI still is a
touch clearer in outline "A" and outline "B" is even more negligible but it is
a bit
cleaner than that same edge on NVIDIA.
Far Cry - Mesh Walkway
Clicking on the thumbnails below will load a
1600x1200 PNG image 300KB~350KB in size
The biggest difference I could
detect here was only at 16x for both cards. Although a very close comparison
here, ATI does appear to provide one more level of clarity as shown in the
outlined area.
IQ ODDITIES That's it for serious IQ comparisons. However, I did find a few oddities in
FarCry that were present on both the X800XT PE and BFG 6800 Ultra OC cards. The
first one appears to be a texture inadvertently stretched over too wide an area.
The second is what I like to call "Rainbow Grass". :) The multicolored effect
was present on both cards but each at different angles and each with varying
colors depending on what level of AF I was running under. Also, it only affected
that particular clump or two of grass.
