Cedartrail zero-copy texture updates

Cedartrail zero-copy texture updates

[Chris Tapp]

I'm trying to get zero-copy GLES textures working using Danny / Cedartrail (PVR) so I can stream video frames into a GLES application.

Googling hasn't really helped that much with how to do this, but I think I need to use eglCreateImageKHR and a client-side buffer so that glEGLImageTargetTexture2DOES() can be used to bind the texture to an image in memory.

eglCreatePixmapSurfaceHI() looks like it allows client memory to be used as a colour-buffer which can be passed to eglCreateImageKHR, but I can't seem to be able to create a context which supports pixmaps.

Are there any examples out there to show how to put all of this together?

Chris Tapp

opensource@keylevel.com
www.keylevel.com

Re: Cedartrail zero-copy texture updates

[Marc Ferland]

On Mon, Feb 24, 2014 at 03:46:07PM +0000, Chris Tapp wrote:
> I'm trying to get zero-copy GLES textures working using Danny /
> Cedartrail (PVR) so I can stream video frames into a GLES
> application.
> 
> Googling hasn't really helped that much with how to do this, but I
> think I need to use eglCreateImageKHR and a client-side buffer so
> that glEGLImageTargetTexture2DOES() can be used to bind the texture
> to an image in memory.
> 
> eglCreatePixmapSurfaceHI() looks like it allows client memory to be
> used as a colour-buffer which can be passed to eglCreateImageKHR,
> but I can't seem to be able to create a context which supports
> pixmaps.
> 
> Are there any examples out there to show how to put all of this
> together?
> 
Documentation about this stuff is indeed sparse and hard to find!

I once tried (and failed!) to do something similar on crownbay but the
texture data was mapped to a polygon mesh (no video acceleration
stuff).

The documentation that I came across mentionned using the
GL_TEXTURE_STREAM_IMG extension to implement the zero-copy texture
transfers. Maybe the same extension is available on cedartrail.

The pdf used to be hosted on intel (emgd section) web site, but it
looks like it was taken down. I can check if I still have it somewhere
if you're interested.

Marc

Re: Cedartrail zero-copy texture updates

[Chris Tapp]

Hi Marc,

On 24 Feb 2014, at 19:21, Marc Ferland <ferlandm@sonatest.com> wrote:

> On Mon, Feb 24, 2014 at 03:46:07PM +0000, Chris Tapp wrote:
>> I'm trying to get zero-copy GLES textures working using Danny /
>> Cedartrail (PVR) so I can stream video frames into a GLES
>> application.
>> 
>> Googling hasn't really helped that much with how to do this, but I
>> think I need to use eglCreateImageKHR and a client-side buffer so
>> that glEGLImageTargetTexture2DOES() can be used to bind the texture
>> to an image in memory.
>> 
>> eglCreatePixmapSurfaceHI() looks like it allows client memory to be
>> used as a colour-buffer which can be passed to eglCreateImageKHR,
>> but I can't seem to be able to create a context which supports
>> pixmaps.
>> 
>> Are there any examples out there to show how to put all of this
>> together?
>> 
> Documentation about this stuff is indeed sparse and hard to find!
> 
> I once tried (and failed!) to do something similar on crownbay but the
> texture data was mapped to a polygon mesh (no video acceleration
> stuff).
> 
> The documentation that I came across mentionned using the
> GL_TEXTURE_STREAM_IMG extension to implement the zero-copy texture
> transfers. Maybe the same extension is available on cedartrail.

I don't think is it. I tried to find this before and could only find GL_IMG_texture_stream2 listed in the GL extensions (for which I can find no documentation!).

> The pdf used to be hosted on intel (emgd section) web site, but it
> looks like it was taken down. I can check if I still have it somewhere
> if you're interested.

Yes please :-)

Chris Tapp

opensource@keylevel.com
www.keylevel.com