[Glamor] [PATCH 1/2] Change the trapezoid render to use VBO

[Michel Dänzer]

On Die, 2012-07-17 at 06:53 +0800, junyan.he at linux.intel.com wrote: 
> From: Junyan He <junyan.he at linux.intel.com>
> 
>  Because some uniform variables need to be set for every
>  trapezoid rendering, we can not use vbo to render multi
>  trapezoids one time, which have performance big loss.
>  We now add attributes which contain the same value to bypass
>  the uniform variable problem. The uniform value for one
>  trapezoid will be set to the same value to all the vertex
>  of that trapezoid as an attribute, then in FS, it is still
>  a constant.
> 
> Signed-off-by: Junyan He <junyan.he at linux.intel.com>

[...]

> +	dispatch->glBindBuffer(GL_ARRAY_BUFFER, glamor_priv->vbo);
> +	if (glamor_priv->gl_flavor == GLAMOR_GL_DESKTOP) {
> +		dispatch->glBufferData(GL_ARRAY_BUFFER,
> +		        glamor_priv->vbo_size,
> +		        NULL, GL_DYNAMIC_DRAW);
> +		glamor_priv->vb = dispatch->glMapBuffer(GL_ARRAY_BUFFER, GL_READ_WRITE);
> +	}

Have you seen the recent changes to glamor_render.c, streaming vertex
data to larger VBOs? I wonder if the same technique could provide a
further speedup here as well. The VBO management code could probably be
shared between the two cases with some refactoring.


-- 
Earthling Michel Dänzer           |                   http://www.amd.com
Libre software enthusiast         |          Debian, X and DRI developer