[PATCH xserver 1/3] glamor: Scissor rectangle drawing to the bounds of the rects.

[Michel Dänzer]

On 02/08/17 05:59 AM, Eric Anholt wrote:
> Scissors provide a critical hint to tiled renderers as to what tiles
> need to be load/stored because they could be modified by the
> rendering.
> 
> The bounds calculation here is limited to when we have a small number
> of rects (large enough to cover rounded window corners, but probably
> not xeyes) to avoid overhead on desktop GL.
> 
> No performance difference on i965 with x11perf -rect1 -repeat 1 -reps
> 10000 (n=50)
> 
> Signed-off-by: Eric Anholt <eric at anholt.net>
> ---
>  glamor/glamor_rects.c | 26 ++++++++++++++++++++++----
>  glamor/glamor_utils.h | 35 +++++++++++++++++++++++++++++++++++
>  2 files changed, 57 insertions(+), 4 deletions(-)
> 
> diff --git a/glamor/glamor_rects.c b/glamor/glamor_rects.c
> index cc029c8c04a6..6cbb040c18ea 100644
> --- a/glamor/glamor_rects.c
> +++ b/glamor/glamor_rects.c
> @@ -53,6 +53,7 @@ glamor_poly_fill_rect_gl(DrawablePtr drawable,
>      char *vbo_offset;
>      int box_index;
>      Bool ret = FALSE;
> +    BoxRec bounds = glamor_no_rendering_bounds();
>  
>      pixmap_priv = glamor_get_pixmap_private(pixmap);
>      if (!GLAMOR_PIXMAP_PRIV_HAS_FBO(pixmap_priv))
> @@ -60,6 +61,12 @@ glamor_poly_fill_rect_gl(DrawablePtr drawable,
>  
>      glamor_make_current(glamor_priv);
>  
> +    if (nrect < 100) {
> +        bounds = glamor_start_rendering_bounds();
> +        for (int i = 0; i < nrect; i++)
> +            glamor_bounds_union_rect(&bounds, &prect[i]);
> +    }

Did your testing hit the nrect == 99 cases? I'd expect those to have the
most potential impact on throughput.


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