[Mesa-dev] [PATCH] gallium: new transfer flag: DISCARD_WHOLE_RESOURCE

[Brian Paul]

On 02/18/2011 09:15 AM, jfonseca at vmware.com wrote:
> From: Keith Whitwell<keithw at vmware.com>
>
> ---
>   src/gallium/include/pipe/p_defines.h |   19 +++++++++++++++++--
>   1 files changed, 17 insertions(+), 2 deletions(-)
>
> diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
> index f66bbaf..2de707f 100644
> --- a/src/gallium/include/pipe/p_defines.h
> +++ b/src/gallium/include/pipe/p_defines.h
> @@ -229,9 +229,9 @@ enum pipe_transfer_usage {
>       *
>       * See also:
>       * - OpenGL's ARB_map_buffer_range extension, MAP_INVALIDATE_RANGE_BIT flag.
> -    * - Direct3D's D3DLOCK_DISCARD flag.
>       */
>      PIPE_TRANSFER_DISCARD = (1<<  8),
> +   PIPE_TRANSFER_DISCARD_RANGE = (1<<  8),

Does the second flag replace the first one?  Are we keeping the first 
one just as a transitory thing?  I'd say to either remove the old one 
or add a comment explaining what's going on.


>      /**
>       * Fail if the resource cannot be mapped immediately.
> @@ -266,7 +266,22 @@ enum pipe_transfer_usage {
>       * - pipe_context::transfer_flush_region
>       * - OpenGL's ARB_map_buffer_range extension, MAP_FLUSH_EXPLICIT_BIT flag.
>       */
> -   PIPE_TRANSFER_FLUSH_EXPLICIT = (1<<  11)
> +   PIPE_TRANSFER_FLUSH_EXPLICIT = (1<<  11),
> +
> +   /**
> +    * Discards all memory backing the resource.
> +    *
> +    * It should not be used with PIPE_TRANSFER_CPU_READ.
> +    *
> +    * This is equivalent to:
> +    * - OpenGL's ARB_map_buffer_range extension, MAP_INVALIDATE_BUFFER_BIT
> +    * - BufferData(NULL) on a GL buffer
> +    * - Direct3D's D3DLOCK_DISCARD flag.
> +    * - WDDM's D3DDDICB_LOCKFLAGS.Discard flag.
> +    * - D3D10 DDI's D3D10_DDI_MAP_WRITE_DISCARD flag
> +    * - D3D10's D3D10_MAP_WRITE_DISCARD flag.
> +    */
> +   PIPE_TRANSFER_DISCARD_WHOLE_RESOURCE = (1<<  12)
>
>   };
>