Re: [Mesa3d-users] Anti-aliasing lines Intel GMA 4500 question

[Brian P. <br...@vm...>]

Stefan Parvu wrote:
> Hi,
> 
>> I don't see any attachments.
> 
> Probable hidden a bit inside bugzilla.
> 
> Here you go:
> 
>   Ubuntu intel gma4500:
>   http://systemdatarecorder.org:9009/bugzilla/attachment.cgi?id=1
> 
>   Solaris nvidia:
>   http://systemdatarecorder.org:9009/bugzilla/attachment.cgi?id=2
> 
>> Are you talking about line antialiasing?
> 
> yep. Im just plotting the Barry coordinates using a simple sequence
> like:
> 
>          /* Enable Anti-aliasing and width of axis */
>          glEnable(GL_LINE_SMOOTH);
>          glEnable(GL_BLEND);
>          glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
>          /* glHint(GL_LINE_SMOOTH_HINT, GL_DONT_CARE); */
>          glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
>          glLineWidth(0.5);
> 
> 
>          glBegin(GL_LINES);
> 
>              /* draw axis */
>              /* Usr Red */
>  	    glColor3f (1.0f, 0.0f, 0.0f);
>  	    glVertex2f(b3Vertex[1][0], b3Vertex[1][1]);
>  	    glVertex2f(op_usr.x, op_usr.y);
> 
>              ...
> 
>          glEnd();
> 
>> I think the 4500 has some limitations w.r.t. antialiased lines.  You might 
>> try settting the INTEL_STRICT_CONFORMANCE env var to 1 and see what happens. 
>> This will turn on software-drawn AA lines.  Performance will be poor, 
>> however.
> 
> thanks. I will try this. I will report back the results.

Just be aware that the quality of AA lines from one GPU/driver to 
another can vary a lot.  I think NVIDIA may have higher quality AA 
lines than other GPUs.

-Brian