plib-devel

Re: [Plib-devel] RE: FlightGears puList code

[Jan R. <slo...@gm...>]

Am Mon, 22 Aug 2005 09:11:46 -0500 schrieb Fay John F Contr AAC/WMG <joh...@eg...>:

> Gentlemen,
> 
> 	In the department of "better late than never" I am revisiting Jan's
> "puaList" code.  I've added a few more things from your code into my

Hello John,

that's good news! I'd really like to see these changes in the next PLIB release.
IMHO the puaList really needs the additional getXXXValue() methods, it
drives you nuts if you try to use getIntegerValue(), the compiler does not
complain (because it inherits the method from puGroup) and it simply
doesn't work...

Kind regards,
Jan R.

-- 
Jan Reucker
email: jan dot reucker at web dot de
web:   http://www.reucker-online.de

Re: [Plib-devel] net/ doesn't build on irix

[Bram S. <br...@sa...>]

M=E5rten Str=F6mberg wrote:

> Strange. How about the following test instead:
>=20
>   #include <sys/types.h>
>   #include <sys/socket.h>
>   socklen_t apa;

Perfect!
works on irix and on linux.

I'll commit the change.
(Only the configure.in in root has this check, others not).

   Bram


> ??
>=20
> -marten
>=20
>=20
> -------------------------------------------------------
> SF.Net email is Sponsored by the Better Software Conference & EXPO
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--=20
Bram Stolk, VR Engineer SARA, Amsterdam.   tel +31 20 592 3000

"Windows is a 32-bit extension to a 16-bit graphical shell for an 8-bit
  operating system originally coded for a 4-bit microprocessor by a 2-bit
  company that can't stand 1 bit of competition."

Re: [Plib-devel] net/ doesn't build on irix

[<ma...@va...>]

Bram Stolk wrote:
>>
>>
>> The configure scripts tries to compile the following:
>>
>>   #include <sys/types.h>
>>   #include <sys/socket.h>
>>   int accept (int, struct sockaddr *, socklen_t *);
>>
>> If it works, then socklen_t is supposed to be defined and nothing needs
>> to be done (no -Dsocklen_t=int or similar).
>>
>> Maybe some other #include is needed for the code to work on IRIX? What
>> does "man 2 accept" say?
>>
> 
> 
> $ man 2 accept
> 
> NAME
>      accept - accept a connection on a socket
> 
> SYNOPSIS
>      #include <sys/types.h>
>      #include <sys/socket.h>
> 
>      int accept (int s, struct sockaddr *addr, socklen_t *addrlen);
> 
>      #if _XOPEN_SOURCE >= 500
>        int accept (int s, struct sockaddr *addr, socklen_t *addrlen);
>      #elif _XOPEN_SOURCE < 500
>        int accept (int s, struct sockaddr *addr, size_t *addrlen);
>      #endif
> 
> but in the logs:
> 
> configure:6718: checking for socklen_t
> configure:6740: cc -c -g -fullwarn  conftest.c >&5
> cc-1143 cc: ERROR File = conftest.c, Line = 31
>   Declaration is incompatible with "int accept(int, void *, socklen_t *)"
>           (declared at line 692 of "/usr/include/sys/socket.h").
> 
>   int accept (int, struct sockaddr *, socklen_t *);
>       ^
> 
> 1 error detected in the compilation of "conftest.c".
> 
> hmm.... why does irix use void ptr as arg?


Strange. How about the following test instead:

  #include <sys/types.h>
  #include <sys/socket.h>
  socklen_t apa;

??

-marten

Re: [Plib-devel] net/ doesn't build on irix

[Bram S. <br...@sa...>]

M=E5rten Str=F6mberg wrote:
> Erik Hofman wrote:
>=20
>>Fay John F Contr AAC/WMG wrote:
>>
>>
>>>So is there anything we need to do to "net" to fix the problem?
>>
>>
>>If anything needs to be changed it should be configure.
>>So far I didn't really bother searching for a proper answer, but lookin=
g
>>at the problem a little better it turns out IRIX defines socklen_t to b=
e
>>of the u_int32_t type unless XOPEN is installed.
>=20
>=20
>=20
> The configure scripts tries to compile the following:
>=20
>   #include <sys/types.h>
>   #include <sys/socket.h>
>   int accept (int, struct sockaddr *, socklen_t *);
>=20
> If it works, then socklen_t is supposed to be defined and nothing needs
> to be done (no -Dsocklen_t=3Dint or similar).
>=20
> Maybe some other #include is needed for the code to work on IRIX? What
> does "man 2 accept" say?
>=20


$ man 2 accept

NAME
      accept - accept a connection on a socket

SYNOPSIS
      #include <sys/types.h>
      #include <sys/socket.h>

      int accept (int s, struct sockaddr *addr, socklen_t *addrlen);

      #if _XOPEN_SOURCE >=3D 500
        int accept (int s, struct sockaddr *addr, socklen_t *addrlen);
      #elif _XOPEN_SOURCE < 500
        int accept (int s, struct sockaddr *addr, size_t *addrlen);
      #endif

but in the logs:

configure:6718: checking for socklen_t
configure:6740: cc -c -g -fullwarn  conftest.c >&5
cc-1143 cc: ERROR File =3D conftest.c, Line =3D 31
   Declaration is incompatible with "int accept(int, void *, socklen_t *)=
"
           (declared at line 692 of "/usr/include/sys/socket.h").

   int accept (int, struct sockaddr *, socklen_t *);
       ^

1 error detected in the compilation of "conftest.c".

hmm.... why does irix use void ptr as arg?

   Bram



> -marten
>=20
>=20
> -------------------------------------------------------
> SF.Net email is Sponsored by the Better Software Conference & EXPO
> September 19-22, 2005 * San Francisco, CA * Development Lifecycle Pract=
ices
> Agile & Plan-Driven Development * Managing Projects & Teams * Testing &=
 QA
> Security * Process Improvement & Measurement * http://www.sqe.com/bsce5=
sf
> _______________________________________________
> plib-devel mailing list
> pli...@li...
> https://lists.sourceforge.net/lists/listinfo/plib-devel


--=20
Bram Stolk, VR Engineer SARA, Amsterdam.   tel +31 20 592 3000

"Windows is a 32-bit extension to a 16-bit graphical shell for an 8-bit
  operating system originally coded for a 4-bit microprocessor by a 2-bit
  company that can't stand 1 bit of competition."

RE: [Plib-devel] RE: FlightGears puList code

[Fay J. F C. AAC/W. <joh...@eg...>]

Gentlemen,

	In the department of "better late than never" I am revisiting Jan's
"puaList" code.  I've added a few more things from your code into my
personal PLIB copy and have added two new constructors, one to make an empty
list and the other to make a filled list, with an additional flag named
"transparent" which, if true, suppresses the creation of the "puFrame"
subwidget.  If there is some call for this, I will upload the changes to
CVS.

John F. Fay
Technical Fellow, Jacobs/Sverdrup TEAS Group
joh...@eg...
850-729-6330 
-----Original Message-----
From: pli...@li...
[mailto:pli...@li...] On Behalf Of Slowhand_47
Sent: Thursday, February 03, 2005 12:35 PM
To: pli...@li...
Subject: Re: [Plib-devel] RE: FlightGears puList code

Am Thu, 03 Feb 2005 18:55:38 +0100 schrieb Erik Hofman <er...@eh...>:

> I would not oppose to a different solution. In fact prior to sending it 
> to John I checked whether plib has already included such a widget. If a 
> different type gets included I will update FlightGear to use that one 
> instead.

It should still be compatible with FG, at least with the 0.9.6
sources from where I took the puList. I removed the underlying
frame, because we use transparency and the extra frame stops the
background from shining through. But the original puList API
should still work, I only added the missing methods from the
puListBox API.

Kind regards,
Jan

-- 
Jan Reucker
email: jan dot reucker at web dot de
web:   http://www.reucker-online.de


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Re: [Plib-devel] net/ doesn't build on irix

[<ma...@va...>]

Erik Hofman wrote:
> Fay John F Contr AAC/WMG wrote:
> 
>> So is there anything we need to do to "net" to fix the problem?
> 
> 
> If anything needs to be changed it should be configure.
> So far I didn't really bother searching for a proper answer, but looking
> at the problem a little better it turns out IRIX defines socklen_t to be
> of the u_int32_t type unless XOPEN is installed.


The configure scripts tries to compile the following:

  #include <sys/types.h>
  #include <sys/socket.h>
  int accept (int, struct sockaddr *, socklen_t *);

If it works, then socklen_t is supposed to be defined and nothing needs
to be done (no -Dsocklen_t=int or similar).

Maybe some other #include is needed for the code to work on IRIX? What
does "man 2 accept" say?

-marten

Re: [Plib-devel] net/ doesn't build on irix

[Erik H. <er...@eh...>]

Bram Stolk wrote:

> btw: I run irix 6.5.27f

You're right, the 6.5.17 bug had something to do with time, but it was 
fixed a long time ago.

Erik

Re: [Plib-devel] net/ doesn't build on irix

[Erik H. <er...@eh...>]

Fay John F Contr AAC/WMG wrote:
> So is there anything we need to do to "net" to fix the problem?

If anything needs to be changed it should be configure.
So far I didn't really bother searching for a proper answer, but looking 
at the problem a little better it turns out IRIX defines socklen_t to be 
of the u_int32_t type unless XOPEN is installed.

Erik

RE: [Plib-devel] net/ doesn't build on irix

[Fay J. F C. AAC/W. <joh...@eg...>]

So is there anything we need to do to "net" to fix the problem?

John F. Fay
Technical Fellow, Jacobs/Sverdrup TEAS Group
joh...@eg...
850-729-6330 
-----Original Message-----
From: pli...@li...
[mailto:pli...@li...] On Behalf Of Bram Stolk
Sent: Sunday, August 21, 2005 10:13 AM
To: pli...@li...
Subject: Re: [Plib-devel] net/ doesn't build on irix

Erik Hofman wrote:

> 
> There is a problem in the header files around IRIX 6.5.17. You can get 
> around it by specifying -D_SOCKLEN_T in the CXXFLAGS and the CFLAGS 
> directive (and run configure again).

It was indeed the socklen thing.
Thanks Martin, and Erik.

btw: I run irix 6.5.27f

   bram





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Re: [Plib-devel] net/ doesn't build on irix

[Martin S. <Mar...@mg...>]

Bram Stolk wrote:

> btw: I run irix 6.5.27f

I would do as well if someone paid the support contract for me  ;-)

Martin.
-- 
 Unix _IS_ user friendly - it's just selective about who its friends are !
--------------------------------------------------------------------------

Re: [Plib-devel] net/ doesn't build on irix

[Bram S. <br...@sa...>]

Erik Hofman wrote:

> 
> There is a problem in the header files around IRIX 6.5.17. You can get 
> around it by specifying -D_SOCKLEN_T in the CXXFLAGS and the CFLAGS 
> directive (and run configure again).

It was indeed the socklen thing.
Thanks Martin, and Erik.

btw: I run irix 6.5.27f

   bram

Re: [Plib-devel] net/ doesn't build on irix

[Erik H. <er...@eh...>]

Martin Spott wrote:
> Bram Stolk wrote:
> 
> 
>>cc-3625 CC: REMARK File = /usr/include/sys/select.h, Line = 35
>>   an include directive is appearing within the scope of extern "C"

This can't be the problem since it is just a remark.
> 
> I've already forgotten why I do this and this probably is not the

There is a problem in the header files around IRIX 6.5.17. You can get 
around it by specifying -D_SOCKLEN_T in the CXXFLAGS and the CFLAGS 
directive (and run configure again).

Erik

Re: [Plib-devel] net/ doesn't build on irix

[Martin S. <Mar...@mg...>]

Bram Stolk wrote:

> cc-3625 CC: REMARK File = /usr/include/sys/select.h, Line = 35
>    an include directive is appearing within the scope of extern "C"
> 
>    #include <standards.h>

I've already forgotten why I do this and this probably is not the
solution to your problem, but I tought I'd tell you that I typically
fix some spots in PLIB when building on IRIX. I run this sript _after_
'configure':

#!/bin/bash
#
for i in `find . -type f -name Makefile`; do
  echo -e ",s/-Dsocklen_t=int//g\nwq" | ed $i
done


Try it out if you like,

	Martin.
-- 
 Unix _IS_ user friendly - it's just selective about who its friends are !
--------------------------------------------------------------------------

Re: [Plib-devel] cvs service shakey?

[LAVIGNE,ERIC <la...@uf...>]

> Also I noticed:
> anon cvs with 
> :pserver:ano...@cv...:/cvsroot/plib
> does not see the change I made.
> 
> Yet, with :ext: access, I do see the change.
> 
> Does anon cvs lag developer cvs, or what?
> 
>    Bram
> 

Bram,

I have run into this issue before also. I made a change to cvs, 
and it took about half a day for that change to show up on 
anonymous cvs. I suspect there is a daily synchronization time.

I don't know anything about your other issue, in which a file was 
lost. I used cvs on only a few occassions and didn't have such 
problems.

Eric

Re: [Plib-devel] new viewer example

[Bram S. <br...@sa...>]

Bram Stolk wrote:

> - orbit works properly (with what I call a virtual ball interface a la 
> perfly)
> 
> - mean/lean/clean (appr one 4th of viewer.cxx size)
> 
> - better suited for instructional use for newbie ssg users due to 
> smaller code.

I forgot the most important benefit: you can run it with any
cwd (current working directory), as it does not depend on a data/
dir. Also, it takes the files a cmdline args, not via menu, so it
is much more suited for a quick scan on how the model looks in plib.
Think of it as a minimalistic 'ivview' for plib :-)

   Bram

[Plib-devel] new viewer example

[Bram S. <br...@sa...>]

Hi there,

examples/src/ssg/viewer/viewer.cxx has a non working orbit function.
I think it's a HPR vs Quat issue, so that you can't orbit directly
overhead of the model.

When I started out fixing this, I noticed that viewer.cxx is quite
complex, and not as lean as it could be.

I've added a new viewer sample (pview.cxx), with the following benefits over
viewer.cxx

- orbit works properly (with what I call a virtual ball interface a la perfly)

- mean/lean/clean (appr one 4th of viewer.cxx size)

- better suited for instructional use for newbie ssg users due to smaller code.

random notes:
-It was tested on linux and irix.
-I did not adapt the win32 project file.
-I left out the freeglut include hack: i don't see why this is req'd:
  I use freeglut myself, but it is simple available as GL/glut.h

   bram

[Plib-devel] cvs service shakey?

[Bram S. <br...@sa...>]

What is it with this sourceforge cvs service?
Upon commiting, I get a warning
"cvs update: warning: pview.cxx was lost"
Is this normal?

Also I noticed:
anon cvs with :pserver:ano...@cv...:/cvsroot/plib
does not see the change I made.

Yet, with :ext: access, I do see the change.

Does anon cvs lag developer cvs, or what?

   Bram

stolk@suske:~/src/plib/examples/src/ssg/viewer$ cvs commit -m "added improved 
viewer example" pview.cxx Makefile.am
br...@cv...'s password:
RCS file: /cvsroot/plib/plib/examples/src/ssg/viewer/pview.cxx,v
done
Checking in pview.cxx;
/cvsroot/plib/plib/examples/src/ssg/viewer/pview.cxx,v  <--  pview.cxx
initial revision: 1.1
done
Checking in Makefile.am;
/cvsroot/plib/plib/examples/src/ssg/viewer/Makefile.am,v  <--  Makefile.am
new revision: 1.8; previous revision: 1.7
done
Mailing pli...@li......
Generating notification message...
Generating notification message... done.

cvs update: warning: pview.cxx was lost
===================================================================
Checking out pview.cxx
RCS:  /cvsroot/plib/plib/examples/src/ssg/viewer/pview.cxx,v
VERS: 1.1
***************
stolk@suske:~/src/plib/examples/src/ssg/viewer$

[Plib-devel] net/ doesn't build on irix

[Bram S. <br...@sa...>]

Hi,

build cvs plib with the net/ component on irix, gives me:

bram@vger:~/src/plib/src/net$ make
CC -DPACKAGE_NAME=\"\" -DPACKAGE_TARNAME=\"\" -DPACKAGE_VERSION=\"\" 
-DPACKAGE_STRING=\"\" -DPACKAGE_BUGREPORT=\"\" -DPACKAGE=\"plib\" 
-DVERSION=\"1.8.4\" -DHAVE_LIBPTHREAD=1 -DHAVE_LIBGL=1 -DHAVE_LIBDL=1 
-DHAVE_LIBAUDIO=1 -DSTDC_HEADERS=1 -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 
-DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHAVE_MEMORY_H=1 -DHAVE_STRINGS_H=1 
-DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -Dsocklen_t=int  -I. -I. 
  -I../../src/util    -I/usr/sara/include -I/home/insight/bram/include -fullwarn 
-c netSocket.cxx
cc-3625 CC: REMARK File = /usr/include/sys/select.h, Line = 35
   an include directive is appearing within the scope of extern "C"

   #include <standards.h>
    ^
I have no idea how to fix this, as the error is in a system hdr file.

Bram

Re: [Plib-devel] OT: engine sound synthesis

[Christos D. <dim...@id...>]

>> So, the best thing to do is to record the engine from very close, then
>> somehow derive the filter description of the whole car, perhaps with
>> the exhaust as a separate model. Then resample the engine sample to
>> the appropriate frequency and pass it through the model. The result is
>> an engine sound.
>
> Thank you for the information,
> Is this what you used in TORCS?
> I could not find the TORCS mailing list thread that Steve referred to.
> Was the sound-synth discussion on torcs-devel sf list? What year?
>

I cannot remember the mailing list discussion. In torcs we just use 
resampling plus a simple low-pass filter in one implementation. 
Anything more complicated will take too much CPU time. Of course some 
cards might be able to deal with that in hardware, but I am not aware 
of any libraries that currently support arbitrary filters in 
hardware at the moment. (Maybe the OpenAL one will, soon).

> I tried out the TORCS debian packages yesterday.
> Although the engine sound is better than what I came up with, it is far
> from perfect. If I use the CVS TORCS with the OpenAL hack, will it sound
> better?
>

The best engine sound is the torcs cvs with plib. The openal version 
does not have the low-pass filter.

-- 
Christos Dimitrakakis
IDIAP (http://www.idiap.ch/~dimitrak/main.html)

Re: [Plib-devel] OT: engine sound synthesis

[Bram S. <br...@sa...>]

On Sat, 13 Aug 2005 04:47:10 +0200 (CEST)
Christos Dimitrakakis <dim...@id...> wrote:

> So, the best thing to do is to record the engine from very close, then 
> somehow derive the filter description of the whole car, perhaps with 
> the exhaust as a separate model. Then resample the engine sample to 
> the appropriate frequency and pass it through the model. The result is 
> an engine sound.

Thank you for the information,
Is this what you used in TORCS?
I could not find the TORCS mailing list thread that Steve referred to.
Was the sound-synth discussion on torcs-devel sf list? What year?

I tried out the TORCS debian packages yesterday.
Although the engine sound is better than what I came up with, it is far 
from perfect. If I use the CVS TORCS with the OpenAL hack, will it sound 
better?

thanks,

  Bram

Re: [Plib-devel] SSG: Using the bitmap loaders for own texture classes?

[Jan R. <slo...@gm...>]

Am Fri, 12 Aug 2005 16:36:43 +0200 schrieb p.l...@ci...:

> You could approach by overriding the default createTexture() method in the
> ssgLoaderOptions class, which is then used by almost all 3D loaders.

Hello Paolo,

thanks for your reply, but I think we're talking about different things.
My problem is the texture bitmap loading (loading a texture file into
memory so that I can access the pixel data), not the texture generation
itself. 

SSG encapsulates all those steps:

- allocate a texture handle
- call a loader function that matches the file extension
- the loader reads the pixel data into memory
- the loader function itself calls ssgMakeMipmaps() on the pixel data
  array for the actual texture generation

What I need:

- call the loader function directly
- manipulate the pixel data (split image into several tiles)
- generate textures from the tiles
- set the texture parameters the way I need them

Only step one is a problem, because I can't use the loader without
automatically invoking ssgMakeMipMaps. The rest is relatively easy.

Kind regards,
Jan R.

-- 
Jan Reucker
email: jan dot reucker at web dot de
web:   http://www.reucker-online.de

Re: [Plib-devel] OT: engine sound synthesis

[Steve B. <sjb...@ai...>]

Christos Dimitrakakis wrote:
>> Isn't there a method that can change playback rates of soundclips without
>> changing the frequencies on the sound?
> 
> 
> It is called time-stretching and it will not work well for this sort of 
> thing. The method you used, resampling is better:
> 
> Engine sound is made up of two things:
> 
> 1) The stimulus, which is created by the firing of the engine, and which 
> it's correct to actually 'resample', by skipping or averaging samples
> 
> 2) The response, which is basically how the engine compartment and 
> exhaust respond to the raw engine sound. You can describe that as some 
> kind of IIR filter, maybe.

And of course there are things in cars that cut in and out depending
on speed, RPM and engine load.  A turbocharger for example has a distinctive
sound but only starts spinning when the engine is producing a certain
amount of exhaust gasses.  At low RPM, it's totally silent - at higher RPM,
it kicks in and changes the engine sound as well as adding it's own sound.

---------------------------- Steve Baker -------------------------
HomeEmail: <sjb...@ai...>    WorkEmail: <sj...@li...>
HomePage : http://www.sjbaker.org
Projects : http://plib.sf.net    http://tuxaqfh.sf.net
            http://tuxkart.sf.net http://prettypoly.sf.net
-----BEGIN GEEK CODE BLOCK-----
GCS d-- s:+ a+ C++++$ UL+++$ P--- L++++$ E--- W+++ N o+ K? w--- !O M-
V-- PS++ PE- Y-- PGP-- t+ 5 X R+++ tv b++ DI++ D G+ e++ h--(-) r+++ y++++
-----END GEEK CODE BLOCK-----

Re: [Plib-devel] OT: engine sound synthesis

[Christos D. <dim...@id...>]

> Isn't there a method that can change playback rates of soundclips without
> changing the frequencies on the sound?

It is called time-stretching and it will not work well for this sort 
of thing. The method you used, resampling is better:

Engine sound is made up of two things:

1) The stimulus, which is created by the firing of the 
engine, and which it's correct to actually 'resample', by skipping or 
averaging samples

2) The response, which is basically how the engine compartment and 
exhaust respond to the raw engine sound. You can describe that as 
some kind of IIR filter, maybe.

So, the best thing to do is to record the engine from very close, then 
somehow derive the filter description of the whole car, perhaps with 
the exhaust as a separate model. Then resample the engine sample to 
the appropriate frequency and pass it through the model. The result is 
an engine sound.

-- 
Christos Dimitrakakis
IDIAP (http://www.idiap.ch/~dimitrak/main.html)

Re: [Plib-devel] OT: engine sound synthesis

[Steve B. <sjb...@ai...>]

Bram Stolk wrote:
> Hello plibbers,
> 
> 
> Sorry for the off-topic mail, but I want to pick the brains on this list.
> 
> I am trying to generate good quality engine sounds.

You should check out the TORCS game's mailing list - they have had
long discussions about the way to do this.

---------------------------- Steve Baker -------------------------
HomeEmail: <sjb...@ai...>    WorkEmail: <sj...@li...>
HomePage : http://www.sjbaker.org
Projects : http://plib.sf.net    http://tuxaqfh.sf.net
            http://tuxkart.sf.net http://prettypoly.sf.net
-----BEGIN GEEK CODE BLOCK-----
GCS d-- s:+ a+ C++++$ UL+++$ P--- L++++$ E--- W+++ N o+ K? w--- !O M-
V-- PS++ PE- Y-- PGP-- t+ 5 X R+++ tv b++ DI++ D G+ e++ h--(-) r+++ y++++
-----END GEEK CODE BLOCK-----

[Plib-devel] OT: engine sound synthesis

[Bram S. <br...@sa...>]

Hello plibbers,


Sorry for the off-topic mail, but I want to pick the brains on this list.

I am trying to generate good quality engine sounds.

After thinking about this, I think that the parameterization of the
engine sound comes down to:
- throttle parameter (open throttle means more sound)
- rpm parameter (higher rpm means 'different' sound).

My first approach failed miserably:
- Completely synthetic solution:
  Generate explosions (white noise with degrading freq's), and
  separate them in time, based on RPM.
This sounds way too synthetic, and not like a real engine.

My second (naive) approach gives bad results as well:
- sampled the engine noise of my chevy small block at idle (1000rpm)
- throttle modulates amplitude
- rpm dictates play-back frequency.
  (at 2000 game RPMs, I skip every other sample from the real life 1000 rpm
   clip).

Isn't there a method that can change playback rates of soundclips without
changing the frequencies on the sound? What is this technique called? And
can it be done in real time? Is it applicable for engine sound synthesis?

Thanks in advance,

  Bram Stolk

PS: I'm not using plib's sl here, because I'm on ALSA, not op OSS.