[Mesa-dev] [PATCH] indices: add comments, assertions in u_indices.c file

[Roland Scheidegger]

On 11/13/2013 06:38 PM, Brian Paul wrote:
> ---
>   src/gallium/auxiliary/indices/u_indices.c |   26 ++++++++++++++++++++++++++
>   1 file changed, 26 insertions(+)
>
> diff --git a/src/gallium/auxiliary/indices/u_indices.c b/src/gallium/auxiliary/indices/u_indices.c
> index 30b54b9..1b33f41 100644
> --- a/src/gallium/auxiliary/indices/u_indices.c
> +++ b/src/gallium/auxiliary/indices/u_indices.c
> @@ -42,6 +42,27 @@ static void translate_memcpy_uint( const void *in,
>   }
>
>
> +/**
> + * Translate indexes when a driver can't support certain types
> + * of drawing.  Example include:
> + * - Translate 1-byte indexes into 2-byte indexes
> + * - Translate PIPE_PRIM_QUADS into PIPE_PRIM_TRIANGLES when the hardware
> + *   doesn't support the former.
> + * - Translate from first provoking vertex to last provoking vertex and
> + *   vice versa.
> + *
> + * \param hw_mask  mask of (1 << PIPE_PRIM_x) flags indicating which types
> + *                 of primitives are supported by the hardware.
> + * \param prim  incoming PIPE_PRIM_x
> + * \param in_index_size  bytes per index value (1, 2 or 4)
> + * \param nr  number of incoming vertices
> + * \param in_pv  incoming provoking vertex convention (PV_FIRST or PV_LAST)
> + * \param out_pv  desired provoking vertex convention (PV_FIRST or PV_LAST)
> + * \param out_prim  returns new PIPE_PRIM_x we'll translate to
> + * \param out_index_size  returns bytes per new index value (2 or 4)
> + * \param out_nr  returns number of new vertices
> + * \param out_translate  returns the translation function to use by the caller
> + */
>   int u_index_translator( unsigned hw_mask,
>                           unsigned prim,
>                           unsigned in_index_size,
> @@ -57,6 +78,10 @@ int u_index_translator( unsigned hw_mask,
>      unsigned out_idx;
>      int ret = U_TRANSLATE_NORMAL;
>
> +   assert(in_index_size == 1 ||
> +          in_index_size == 2 ||
> +          in_index_size == 4);
> +
>      u_index_init();
>
>      in_idx = in_size_idx(in_index_size);
> @@ -67,6 +92,7 @@ int u_index_translator( unsigned hw_mask,
>          in_index_size == *out_index_size &&
>          in_pv == out_pv)
>      {
> +      /* Index translation not really needed */
>         if (in_index_size == 4)
>            *out_translate = translate_memcpy_uint;
>         else
>

Reviewed-by: Roland Scheidegger <sroland at vmware.com>