[cairo] acceleration

[Patrick Shirkey]

On Wed, October 3, 2012 10:03 am, Henry (Yu) Song - SISA wrote:
> Hi, Patrix
>
> The answer to your question is YES, cairo runs on Opengl and Opengl es 2.0
> (no gles 1 though).  I might be able to help you more if you can give me
> more info on your gl driver.  Is it open source intel, radeon, nouveau
> driver? it is ATI fglrx driver or NVidia unified driver?  Are you running
> on embedded device with Opengl es  2, what is the embedded GPU/driver?
>

The machine I am developing on is running the nouveau driver and the
device is

 NVIDIA Corporation G96 [Quadro FX 580]

I have tested the cairo_gl_surface example code on this machine and it
loads the gears example and various clutter examples too.

I porting an app from that other os to Linux and I would like to be able
to reuse the existing opengl code so it looks like cairo_gl_surface is the
way to go for that task as I have been told clutter only has support for
gles.

My options at the moment are:

1: Port the cairo_gl_surface example from c to python3
2: Port the existing opengl to gles and load in clutter
3: Reimplement the existing opengl code as clutter/cogl

I would prefer to do 1 but at the moment the only code I can get to run in
python is the clutter examples so I have to make a decision.



Patrick



> They are all different.
>
> Henry
> ________________________________________
> From: cairo-bounces+henry.song=samsung.com at cairographics.org
> [cairo-bounces+henry.song=samsung.com at cairographics.org] on behalf of
> Patrick Shirkey [pshirkey at boosthardware.com]
> Sent: Tuesday, October 02, 2012 4:25 PM
> To: cairo at cairographics.org
> Subject: Re: [cairo] acceleration
>
> On Wed, October 3, 2012 9:10 am, Henry (Yu) Song - SISA wrote:
>> I am not sure your question.  acceleration in gl driver? or acceleration
>> using gl-backend vs. image-backend in cairo?
>>
>
> According to wikipedia cairo "uses acceleration when available". So as
> that is rather vague I need to prove or disprove that cairo will use the
> GPU for 2d acceleration for the image-backend. My experience with cairo on
> gtk2 suggests that the computations are handled by the cpu unless
> explicitly requested to use cairo_gl_surface.
>
>
>> if you want to use gl backend, create cairo_gl_surface instead of using
>> cairo_image_surface.  Again, the performance of cairo_gl_surface vs.
>> cairo_image_surface depends on your gl driver quality as Chris said.
>>
>
> Thanks, does cairo_gl_surface work with all opengl or only opengl es ?
>
>
>> Henry
>> ________________________________________
>> From: cairo-bounces+hsong=sisa.samsung.com at cairographics.org
>> [cairo-bounces+hsong=sisa.samsung.com at cairographics.org] on behalf of
>> Patrick Shirkey [pshirkey at boosthardware.com]
>> Sent: Tuesday, October 02, 2012 3:46 PM
>> To: cairo at cairographics.org
>> Subject: Re: [cairo] acceleration
>>
>> On Tue, October 2, 2012 9:39 pm, Chris Wilson wrote:
>>> On Tue, 2 Oct 2012 21:25:43 +1000 (EST), "Patrick Shirkey"
>>> <pshirkey at boosthardware.com> wrote:
>>>>
>>>> On Tue, October 2, 2012 9:16 pm, Chris Wilson wrote:
>>>> > On Tue, 2 Oct 2012 15:35:38 +1000 (EST), "Patrick Shirkey"
>>>> > <pshirkey at boosthardware.com> wrote:
>>>> >> Hi,
>>>> >>
>>>> >> Is there a simple test to know if cairo is using acceleration or is
>>>> it
>>>> >> just a matter of running a desktop with glx?
>>>> >
>>>> > Cairo dodges the complicated question of how to setup the rendering
>>>> > pipeline leaving that to the application/toolkit. So in order for
>>>> cairo
>>>> > to use GL, the application must create a set of output Windows
>>>> > compatible with GL and pass those and the context to cairo to use.
>>>> The
>>>> > degree of acceleration then depends upon the quality of the driver
>>>> and
>>>> > the style of rendering. In short, do not expect to switching to
>>>> cairo-gl
>>>> > to be an easy task to get fast rendering.
>>>>
>>
>>
>> In terms of 2d acceleration how would I know if cario is using the GPU
>> or
>> CPU?
>>
>>
>>
>>
>>>> Thanks Chris.
>>>>
>>>> Is the recommended approached to use cogl directly, cairo or clutter?
>>>
>>> Use the appropriate tool to hand :)
>>>
>>> Clutter is excellent for controlling animations and emergent behaviour.
>>> Cairo offers a simple means for describing a page layout (or parts
>>> there
>>> of).
>>> Cogl aims to make using OpenGL simpler and more portable, with a few
>>> additional smarts.
>>>
>>>> FYI, I am using python3 with gtk3 and so far the only code I have been
>>>> able to make work with this combination are the clutter examples.
>>>>
>>>> I have some existing opengl. I am looking at either porting it to
>>>> cogl/clutter or if there is a way to load it directly with cairo that
>>>> I
>>>> have yet to come across.
>>>
>>> If you are starting from OpenGL, probably easier to go to clutter+cogl.
>>> Cairo comes into its own for having a higher level description of paths
>>> and shapes, but if you already are well versed in translating into
>>> OpenGL, then you probably do not need Cairo and will probably be better
>>> to avoid the impedance mismatch between the PDF rendering model and
>>> OpenGL. However, if Cairo makes your design and maintenance easier,
>>> have
>>> fun!
>>> -Chris
>>>
>>> --
>>> Chris Wilson, Intel Open Source Technology Centre
>>>
>>
>>
>> --
>> Patrick Shirkey
>> Boost Hardware Ltd
>> --
>> cairo mailing list
>> cairo at cairographics.org
>> http://lists.cairographics.org/mailman/listinfo/cairo
>>
>
>
> --
> Patrick Shirkey
> Boost Hardware Ltd
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> cairo mailing list
> cairo at cairographics.org
> http://lists.cairographics.org/mailman/listinfo/cairo
>


--
Patrick Shirkey
Boost Hardware Ltd