[Mesa-dev] [PATCH] mesa/main/readpix: Correct handling of packed floating point values

[Ian Romanick]

On 04/27/2018 09:04 AM, Gert Wollny wrote:
> From: Gert Wollny <gert.wollny at collabora.com>
> 
> Make sure that clamping in the pixel transfer operations is enabled/disabled
> for packed floating point values just like it is done for single normal and
> half precision floating point values.
> 
> This fixes a series of CTS tests with virgl that use r11f_g11f_b10f
> buffers as target, and where virglrenderer reads these surfaces back 
> using the format GL_UNSIGNED_INT_10F_11F_11F_REV.
> 
> Signed-off-by: Gert Wollny <gert.wollny at collabora.com>
> ---
> PS: I don't have write permissions to mesa git
> 
>  src/mesa/main/readpix.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/src/mesa/main/readpix.c b/src/mesa/main/readpix.c
> index a4eea3043d..c5fc66988b 100644
> --- a/src/mesa/main/readpix.c
> +++ b/src/mesa/main/readpix.c
> @@ -106,7 +106,8 @@ _mesa_get_readpixels_transfer_ops(const struct gl_context *ctx,
>        /* For blit-based ReadPixels packing, the clamping is done automatically
>         * unless the type is float. */
>        if (_mesa_get_clamp_read_color(ctx, ctx->ReadBuffer) &&
> -          (type == GL_FLOAT || type == GL_HALF_FLOAT)) {
> +          (type == GL_FLOAT || type == GL_HALF_FLOAT ||
> +           type == GL_UNSIGNED_INT_10F_11F_11F_REV)) {

I was thinking that maybe we needed to handle another type or two here,
but I verified that those type (e.g., the 999e5 type) aren't possible.
I'm going to run this through Intel's CI, then push it.

Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

>           transferOps |= IMAGE_CLAMP_BIT;
>        }
>     }
> @@ -114,7 +115,8 @@ _mesa_get_readpixels_transfer_ops(const struct gl_context *ctx,
>        /* For CPU-based ReadPixels packing, the clamping must always be done
>         * for non-float types, */
>        if (_mesa_get_clamp_read_color(ctx, ctx->ReadBuffer) ||
> -          (type != GL_FLOAT && type != GL_HALF_FLOAT)) {
> +          (type != GL_FLOAT && type != GL_HALF_FLOAT &&
> +           type != GL_UNSIGNED_INT_10F_11F_11F_REV)) {
>           transferOps |= IMAGE_CLAMP_BIT;
>        }
>     }
>