Accurate Timing in ruby

ruby-talk
1

does that help?

···

------------------------------------------------------------------------
--

require "Win32API"

QueryPerformanceCounter = Win32API.new("kernel32",
"QueryPerformanceCounter", 'P', 'I')
QueryPerformanceFrequency = Win32API.new("kernel32",
"QueryPerformanceFrequency", 'P', 'I')

def get_ticks
    tick = ' ' * 8
    get_ticks = QueryPerformanceCounter.call(tick)
    tick.unpack('q')[0]
end

def get_freq
    freq = ' ' * 8
    get_freq = QueryPerformanceFrequency.call(freq)
    freq.unpack('q')[0]
end

ticks1 = get_ticks
sleep 1.5
ticks2 = get_ticks

p (ticks2 - ticks1).to_f / (get_freq)

------------------------------------------------------------------------
--

cheers

Simon

-----Original Message-----
From: Harold Hausman [mailto:hhausman@gmail.com]
Sent: Friday, November 11, 2005 5:04 PM
To: ruby-talk ML
Subject: Re: Accurate Timing in ruby

Silly Windows.
I haven't looked at the source but it sounds like it might be using
::GetTickCount(), if thats the case it could probably be
refactored to use
::QueryPerformanceCounter() which is a significantly higher resolution
timer. Of course, then questions of 9x compatibility come up.
The idea of using the SDL wrapper for making a game is
probably a good one
though.
-Harold

On 11/11/05, Robert McGovern <robert.mcgovern@gmail.com> wrote:
>
> > > So my PDA is more accurate than your machine (what OS is that?)
> >
> > Windows XP.
> > I think I got better accuracy on my iBook as well, so
it's probably a
> > limitation of the OS functions ruby uses to retreive the time on
> Windows.
>
> Mmm, I think your right ... my XP box reports:
>
> irb(main):001:0> a=Time.now;while Time.now==a;end;Time.now-a
> => 0.016
>
> for a Athlon 2800.
>
>

2

That looks legit,
Wheres that from?
-Harold

···

On 11/11/05, Kroeger, Simon (ext) <simon.kroeger.ext@siemens.com> wrote:

does that help?

------------------------------------------------------------------------
--

require "Win32API"

QueryPerformanceCounter = Win32API.new("kernel32",
"QueryPerformanceCounter", 'P', 'I')
QueryPerformanceFrequency = Win32API.new("kernel32",
"QueryPerformanceFrequency", 'P', 'I')

def get_ticks
tick = ' ' * 8
get_ticks = QueryPerformanceCounter.call(tick)
tick.unpack('q')[0]
end

def get_freq
freq = ' ' * 8
get_freq = QueryPerformanceFrequency.call(freq)
freq.unpack('q')[0]
end

ticks1 = get_ticks
sleep 1.5
ticks2 = get_ticks

p (ticks2 - ticks1).to_f / (get_freq)

------------------------------------------------------------------------
--

cheers

Simon

> -----Original Message-----
> From: Harold Hausman [mailto:hhausman@gmail.com]
> Sent: Friday, November 11, 2005 5:04 PM
> To: ruby-talk ML
> Subject: Re: Accurate Timing in ruby
>
> Silly Windows.
> I haven't looked at the source but it sounds like it might be using
> ::GetTickCount(), if thats the case it could probably be
> refactored to use
> ::QueryPerformanceCounter() which is a significantly higher resolution
> timer. Of course, then questions of 9x compatibility come up.
> The idea of using the SDL wrapper for making a game is
> probably a good one
> though.
> -Harold
>
> On 11/11/05, Robert McGovern <robert.mcgovern@gmail.com> wrote:
> >
> > > > So my PDA is more accurate than your machine (what OS is that?)
> > >
> > > Windows XP.
> > > I think I got better accuracy on my iBook as well, so
> it's probably a
> > > limitation of the OS functions ruby uses to retreive the time on
> > Windows.
> >
> > Mmm, I think your right ... my XP box reports:
> >
> > irb(main):001:0> a=Time.now;while Time.now==a;end;Time.now-a
> > => 0.016
> >
> > for a Athlon 2800.
> >
> >
>

3

Harold Hausman wrote:

That looks legit,
Wheres that from?
-Harold

from me :slight_smile:

and it should work on win9x:

Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.

cheers

Simon