Loading...

mac-opengl@lists.apple.com

[Prev] Thread [Next]  |  [Prev] Date [Next]

Re: Weird figures with OpenGL 3.2 and Intel HD3000 Filip Wänström Thu Feb 02 06:07:48 2012

The thing that stands out to my eyes here is that since you try to
draw quite a few indexed triangles you are out of range for
GL_UNSIGNED_SHORT. Why not use GL_UNSIGNED_INT ? Also, how to you
measure drawing time for the calls?Are you really getting values that
you can trust?
Regards
/Filip

On Wed, Jan 18, 2012 at 10:27 AM, vincent habchi <[EMAIL PROTECTED]> wrote:
> Hej Ingemar, Hi Justin,
> thanks for your answers!
>
>> 400000 triangles is a lot, but when 15000 takes the same time, there is 
>> another bottleneck somewhere. What happens for very small models? Still 10 
>> ms? How about drawing several? Maybe the overhead is somewhere else?
>
> I have to try.
>
>> I can try the same program on a 9400 if you like, to see if it is the same 
>> for other GPUs.
>
> When I run the very same code on my late 2008 old MacBook, with the 
> integrated NVidia 9400M chip (which is not supposed to be a racing horse), 
> the same call to glDrawElements takes *20 µs* on average; that’s much less 
> that the customary call to glClear (GL_COLOR_BUFFER_BIT) that consumes around 
> 90 µs.
> (BTW, I made a mistake in my first message. On the HD3000, it takes 10 ms, 
> not 10 µs).
>
>>> You are rendering quite a bit of geometry, do you have another
>>> benchmark to test it against to see how your Mac performs with that?
>>> My experience with intel graphics is not great and It wouldn't
>>> surprise me if you are maxing it out.
>
> Justin, while I can conceive Intel HD3000 performance to be on par or 
> slightly inferior to a 3+ years old NVidia 9400M, here the difference is 
> about three orders of magnitude, which makes me think there is a hidden bug 
> somewhere in the driver (?). It is as if none of the two VBO (position, 
> indices) and none of the texture were actually cached in the GPU memory, and 
> all had to be transferred anew at each frame.
>
> Very strange indeed.
>
> Anyhow,
> thanks Justin,
> tack så mycket Ingemar,
>
> Vincent
>
>  _______________________________________________
> Do not post admin requests to the list. They will be ignored.
> Mac-opengl mailing list      ([EMAIL PROTECTED])
> Help/Unsubscribe/Update your Subscription:
> http://lists.apple.com/mailman/options/mac-opengl/filip.wanstrom%40gmail.com
>
> This email sent to [EMAIL PROTECTED]



-- 
Filip Wänström
Interactive Institute C-Studio
[EMAIL PROTECTED]
+46(0)70 674 2604
www.tii.se/c-studio
www.visualiseringscenter.se/
 _______________________________________________
Do not post admin requests to the list. They will be ignored.
Mac-opengl mailing list      ([EMAIL PROTECTED])
Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/mac-opengl/alexiscircle%40gmail.com

This email sent to [EMAIL PROTECTED]