a couple of follow-up questions<br><br><div class="gmail_quote">On Wed, Mar 4, 2009 at 1:02 AM, Chris Wilson <span dir="ltr"><<a href="mailto:chris@chris-wilson.co.uk">chris@chris-wilson.co.uk</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div class="im">On Tue, 2009-03-03 at 17:24 -0800, Bipin George Mathew wrote:<br>
> I was looking into way of accelerating Cairo using a glitz-backend and<br>
> had a bunch of related questions:<br>
><br>
> - What is the current status of glitz? Is anyone working on it?<br>
<br>
</div>People contribute patches occasionally, just recently we received quite<br>
a few to address some bit rot and improve conformance.<br>
<div class="im"><br>
> - From the paper here<br>
> <a href="http://www.usenix.org/events/usenix04/tech/freenix/full_papers/nilsson/nilsson_html/index.html" target="_blank">http://www.usenix.org/events/usenix04/tech/freenix/full_papers/nilsson/nilsson_html/index.html</a>, it looks like glitz was experimental. What are the areas that needs to be worked on in-order to make it mainstream?<br>
<br>
</div>For glitz to be considered supported we essentially need two things:<br>
1. It should pass the test suite.</blockquote><div><br>What test suite are we talking about here? <br><br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
2. A responsive and long-term maintainer (for both the cairo backend the<br>
glitz library).
<div class="im"></div></blockquote><div> </div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div class="im"><br>
> - What are the other options of accelerating Cairo?<br>
<br>
</div>Glitz was an experiment to implement the XRender protocol on top of<br>
OpenGL. This may not be the best approach to take. Instead the emphasis<br>
has shifted onto using the "new" (introduced into cairo after glitz was<br>
conceived) high level backend api</blockquote><div>Is this an OpenGl based API we talking about here? <br> </div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
to offload as much of the drawing<br>
operation as possible to the h/w. (Or at least entertain that<br>
possibility and investigate different solutions.)<br>
<br>
So currently aside from glitz, there are experiments to show that simply<br>
doing basic compositing using OpenGL can be much faster than XRender:<br>
<a href="http://cgit.freedesktop.org/%7Eanholt/cairo/log/?h=gl" target="_blank">http://cgit.freedesktop.org/~anholt/cairo/log/?h=gl</a> and<br>
<a href="http://cgit.freedesktop.org/%7Eickle/cairo/log/?h=opengl" target="_blank">http://cgit.freedesktop.org/~ickle/cairo/log/?h=opengl</a> A slightly more<br>
ambitious (though it does have quite a few fundamental flaws of its own,<br>
chiefly among those is that he hasn't asked anyone from the cairo<br>
community to review it...)<br>
<a href="http://github.com/akyrtzi/cairo-gral/tree/master" target="_blank">http://github.com/akyrtzi/cairo-gral/tree/master</a> And my favourite<br>
(slightly biased since I'm the author ;-) is an example of what you can<br>
achieve with direct rendering:<br>
<a href="http://cgit.freedesktop.org/%7Eickle/cairo/log/?h=drm" target="_blank">http://cgit.freedesktop.org/~ickle/cairo/log/?h=drm</a> which, I claim, is<br>
just about as fast as you can make cairo on an eee/i915. (I welcome any<br>
patches to make it, and cairo, even faster :-)<br>
<br>
-ickle<br>
<br>
</blockquote></div><br>