Reaction time, was Re: [SDL] Portability versus the "Gee Whiz" factor

[Bob Pendleton]

HaB JacKaL wrote:
>>
>> That's ridiculous. Human eye can't recognize more than 25fps. If your 
>> game works at 45fps on your base target,
>> well you can lower your base target. :)
>>
> 
> Perhaps the eye can't recognize the difference, but you can definately 
> tell a difference in the responsiveness of the controls.  Try aiming 
> accurately in Quake 3 at 30fps, then try again at 65fps.  YOu will 
> notice a HUGE difference in the way everything feels at 60fps.

The US military learned from the very first flight simulators that the 
time from when a control input is entered into the simulator to the time 
the reaction is seen must not be more than 100 milliseconds or the 
simulator actually reduce the pilots skills. This rule applies to action 
games too.

In a game you are usually viewing one frame, while another frame is 
being drawn, amd your input will becomes visible in the frame after 
that. In other words there is a 2 to 3 frame delay between the time you 
move a mouse and the time you see the result. At 30 fps (33.33... 
milliseconds per frame) you are right at the 100 millisecond limit. At 
60 fps (16.66... milliseconds per frame) you see the effect of your 
input with a 50 millisecond delay. (This all assumes double buffering, a 
triple buffered system adds one more frame of delay.)

Thanks for point this out, I had forgotten about this effect. This 
implies that for action games 30 fps is the MINIMUM you should aim for 
with 60+ being the goal.

		Bob Pendleton

> 
> -HaB
> 
> 
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+------------------------------------------+
+ Bob Pendleton, an experienced C/C++/Java +
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