On OSX and Linux pix_share_write and pix_share_read use shared memory between applications to pass pix_ frames.  The setup requires giving the shared memory a numeric id, width, height and bits per pixel of the frame.  After this frames written by one pd instance can be read from any other pd. 

OSX will require changing shm defaults in /etc/rc in order to use HD size textures.

On Feb 19, 2008 10:27 AM, simon wise <simonxwise@hotmail.com> wrote:

On 19 Feb 2008, at 6:46 PM, tim wrote:

> simon wise wrote:
>>
>> On 19 Feb 2008, at 12:06 AM, tim wrote:
>>
>>> Sergi Lario wrote:
>>>>
>>>> Hi. I trying to create 2 channel videomixer in pd/gem. And now
>>>> have 2
>>>> questions- how i can make 2 gemwin's to use 1 as preview and
>>>> other as
>>>> output, and second- how i can make file list or grid of images to
>>>> preview my videofiles and then load it's to pix_film. Big thx.
>>>>
>>>>
>>>> Hi.
>>>>
>>>> About multiple gemwin at same time: I don't know if it's
>>>> possible, but
>>>> it would be very useful.
>>>>
>>> Hi Sergi,
>>>
>>> I've done stuff with two gemwins by running pd 2 times and have
>>> the two
>>> instances communicate over OSC.
>>> It worked quite well.
>>
>> a while ago there was a multiple-Gemwin version of Gem around - I
>> tried out the binary that was available and it worked fine (I
>> think on OSX but possibly Linux?) but I used the 2 pd method
>> instead for my project.
>>
>> I don't know if it is possible for one pd to use textures or
>> buffers created in the other, that would make the preview idea
>> work well with two pd instances.
> My idea was rather to simply sync the messages so that the same
> video file is loaded by the two pd's separately.
> I wasn't using any texturing with this setup though, so I don't
> know if it would work.
>> Soon I want to try 2 camera views of the same 3D space, I think
>> that would be much easier in a single instance of pd with two
>> windows!
> Load the same 3D space in the two pd's and relate the control data
> in some way ?

without textures and lots of pix work this is fine - but I'm wanting
to use plenty of movies and largish graphics as textures, which would
be present from a different point of view in each of the windows.

It would be better to only read from the drive once, then decode
using the CPU a single time, and to only transfer one copy to the
graphics card - so it seems either 2 windows in a single pd or a way
to pass references to textures already loaded between 2 different
pd's is what I'm looking for, but I'll fall back on one machine per
projector if required.


simon




_______________________________________________
PD-list@iem.at mailing list
UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list