Fps - how it works];->

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Fps - how it works];->

Post  beavisboss on Fri Dec 07 2007, 10:38

Frame rate

Frame rate, or frame frequency, is the measurement of the frequency (rate) at which an imaging device produces unique consecutive images called frames. The term applies equally well to computer graphics, video cameras, film cameras, and motion capture systems. Frame rate is most often expressed in frames per second (fps), or simply hertz (Hz).
Frame rates in video games

Frame rates are considered important in video games. The frame rate
can make the difference between a game that is playable and one that is
not. The first 3D first-person adventure game for a personal computer, 3D Monster Maze,
had a frame rate of approximately 6 fps, and was still a success, being
playable and addictive. In modern action-oriented games where players
must visually track animated objects and react quickly, frame rates of
between 30 to 60 fps are considered minimally acceptable by some,
though this can vary significantly from game to game. Most modern
action games, including popular first person shooters such as Halo 3,
run around 30 frames a second, while others, such as Call of Duty 4,
run at 60 frames a second. The framerate within most games,
particularly PC games, will depend upon what is currently happening in
the game in the way of CPU occupying.
A culture of competition has arisen among game enthusiasts with
regards to frame rates, with players striving to obtain the highest fps
count possible. Indeed, many benchmarks released by the marketing
departments of hardware manufacturers and published in hardware reviews
focus on the fps measurement. Modern video cards, often featuring NVIDIA or ATI chipsets, can perform at over 160 fps on graphics intensive games such as F.E.A.R. One single GeForce 8800 GTX has been reported to play F.E.A.R. at up to 386 fps (at a low resolution).[citation needed] This does not apply to all games: some games apply a limit on the frame rate. For example, in the Grand Theft Auto series, Grand Theft Auto III and Grand Theft Auto: Vice City have a standard 30 fps (Grand Theft Auto: San Andreas
runs at 25 fps) and this limit can only be removed at the cost of
graphical and gameplay stability. It is also doubtful whether striving
for such high frame rates is worthwhile. An average 17" monitor can
reach 85 Hz, meaning that any performance reached by the game over 85
fps is discarded. For that reason it is not uncommon to limit the frame
rate to the refresh rate of the monitor in a process called vertical synchronization. However, many players feel that not synchronizing every frame produces sufficiently better game execution to justify some "tearing" of the images.
It should also be noted that there is a rather large controversy
over what is known as the "feel" of the game frame rate. It is argued
that games with extremely high frame rates "feel" better and smoother
than those that are just getting by. This is especially true in games
such as a first-person shooter.
There is often a noticeable choppiness perceived in most computer
rendered video, despite it being above the flicker fusion frequency
(as, after all, one's eyes are not synchronized to the monitor).
This choppiness is not a perceived flicker, but a perceived gap between the object in motion and its afterimage
left in the eye from the last frame. A computer samples one point in
time, then nothing is sampled until the next frame is rendered, so a
visible gap can be seen between the moving object and its afterimage in
the eye. Many driving games have this problem, like NASCAR 2005: Chase for the Cup for Xbox, and Gran Turismo 4.
The polygon count in a frame may be too much to keep the game running
smoothly for a second. The processing power needs to go to the polygon
count and usually takes away the power from the framerate.
The reason computer rendered video has a noticeable afterimage
separation problem and camera captured video does not is that a camera
shutter interrupts the light two or three times for every film frame,
thus exposing the film to 2 or 3 samples at different points in time.
The light can also enter for the entire time the shutter is open, thus
exposing the film to a continuous sample over this time. These multiple
samples are naturally interpolated together on the same frame. This
leads to a small amount of motion blur between one frame and the next which allows them to smoothly transition.
An example of afterimage separation can be seen when taking a quick
180 degree turn in a game in only 1 second. A still object in the game
would render 60 times evenly on that 180 degree arc (at 60 Hz frame
rate), and visibly this would separate the object and its afterimage by
3 degrees. A small object and its afterimage 3 degrees apart are quite
noticeably separated on screen.
The solution to this problem would be to interpolate the extra frames together in the back-buffer (field multisampling), or simulate the motion blur seen by the human eye
in the rendering engine. When vertical sync is enabled, video cards
only output a maximum frame rate equal to the refresh rate of the
monitor. All extra frames are dropped. When vertical sync is disabled,
the video card is free to render frames as fast as it can, but the
display of those rendered frames is still limited to the refresh rate
of the monitor. For example, a card may render a game at 100 FPS on a
monitor running 75 Hz refresh, but no more than 75 FPS can actually be
displayed on screen.
Certain elements of a game may be more GPU-intensive
than others. While a game may achieve a fairly consistent 60 fps, the
frame rate may drop below that during intensive scenes. By achieving
frame rates in excess of what is displayable, it makes it less likely
that frame rates will drop below what is displayable during stressful
scenes.



And to play kal you must have at least 60fps to play-so good graphic card 128mb+ and at least processor 1,7ghz+ with 256mb ram. I have now graph. card 4mb(woot...) 861mhz processor and 256mb ram. So when i see mobs i have 1fps and see only screens,when not too much pple near me i have 14fps. And thats why i cant play with you right now ;/
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