[Mesa-dev] [PATCH v2 04/23] mesa: Fix A1R5G5B5 packing/unpacking

[Ian Romanick]

On 12/01/2014 03:04 AM, Iago Toral Quiroga wrote:
> From: Jason Ekstrand <jason.ekstrand at intel.com>
> 
> As with B5G6R5, these have been left broken with comments saying they are.
> 
> Signed-off-by: Jason Ekstrand <jason.ekstrand at intel.com>
> ---
>  src/mesa/main/format_pack.c      |  8 +-------
>  src/mesa/main/format_unpack.c    | 11 ++++-------
>  src/mesa/main/formats.c          |  2 ++
>  src/mesa/swrast/s_texfetch_tmp.h |  8 ++++----
>  4 files changed, 11 insertions(+), 18 deletions(-)
> 
> diff --git a/src/mesa/main/format_pack.c b/src/mesa/main/format_pack.c
> index 20d2b1a..3d191c1 100644
> --- a/src/mesa/main/format_pack.c
> +++ b/src/mesa/main/format_pack.c
> @@ -584,17 +584,11 @@ pack_float_B5G5R5A1_UNORM(const GLfloat src[4], void *dst)
>     pack_ubyte_B5G5R5A1_UNORM(v, dst);
>  }
>  
> -
> -/* MESA_FORMAT_A1R5G5B5_UNORM
> - * Warning: these functions do not match the current Mesa definition
> - * of MESA_FORMAT_A1R5G5B5_UNORM.
> - */
> -
>  static void
>  pack_ubyte_A1R5G5B5_UNORM(const GLubyte src[4], void *dst)
>  {
>     GLushort *d = ((GLushort *) dst), tmp;
> -   tmp = PACK_COLOR_1555(src[ACOMP], src[RCOMP], src[GCOMP], src[BCOMP]);
> +   tmp = PACK_COLOR_5551(src[BCOMP], src[GCOMP], src[RCOMP], src[ACOMP]);
>     *d = (tmp >> 8) | (tmp << 8);
>  }
>  
> diff --git a/src/mesa/main/format_unpack.c b/src/mesa/main/format_unpack.c
> index f5ab966..8a95fad 100644
> --- a/src/mesa/main/format_unpack.c
> +++ b/src/mesa/main/format_unpack.c
> @@ -2827,17 +2827,14 @@ unpack_ubyte_B5G5R5A1_UNORM(const void *src, GLubyte dst[][4], GLuint n)
>  static void
>  unpack_ubyte_A1R5G5B5_UNORM(const void *src, GLubyte dst[][4], GLuint n)
>  {
> -   /* Warning: this function does not match the current Mesa definition
> -    * of MESA_FORMAT_A1R5G5B5_UNORM.
> -    */
>     const GLushort *s = ((const GLushort *) src);
>     GLuint i;
>     for (i = 0; i < n; i++) {
>        GLushort tmp = (s[i] << 8) | (s[i] >> 8); /* byteswap */
> -      dst[i][RCOMP] = EXPAND_5_8((tmp >> 10) & 0x1f);
> -      dst[i][GCOMP] = EXPAND_5_8((tmp >>  5) & 0x1f);
> -      dst[i][BCOMP] = EXPAND_5_8((tmp >>  0) & 0x1f);
> -      dst[i][ACOMP] = EXPAND_1_8((tmp >> 15) & 0x01);
> +      dst[i][RCOMP] = EXPAND_5_8((tmp >>  1) & 0x1f);
> +      dst[i][GCOMP] = EXPAND_5_8((tmp >>  6) & 0x1f);
> +      dst[i][BCOMP] = EXPAND_5_8((tmp >> 11) & 0x1f);
> +      dst[i][ACOMP] = EXPAND_1_8((tmp      ) & 0x01);
>     }
>  }
>  
> diff --git a/src/mesa/main/formats.c b/src/mesa/main/formats.c
> index 1315d36..7ec0507 100644
> --- a/src/mesa/main/formats.c
> +++ b/src/mesa/main/formats.c
> @@ -1487,6 +1487,8 @@ _mesa_format_matches_format_and_type(mesa_format mesa_format,
>           !swapBytes;
>  
>     case MESA_FORMAT_A1R5G5B5_UNORM:
> +      return format == GL_BGRA && type == GL_UNSIGNED_SHORT_5_5_5_1 &&
> +         !swapBytes;
>        return GL_FALSE;

Delete the unreachable return.

With that fixed, this patch is

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

>  
>     case MESA_FORMAT_L4A4_UNORM:
> diff --git a/src/mesa/swrast/s_texfetch_tmp.h b/src/mesa/swrast/s_texfetch_tmp.h
> index 23db48d..e3a3cfe 100644
> --- a/src/mesa/swrast/s_texfetch_tmp.h
> +++ b/src/mesa/swrast/s_texfetch_tmp.h
> @@ -482,10 +482,10 @@ FETCH(A1R5G5B5_UNORM)(const struct swrast_texture_image *texImage,
>  {
>     const GLushort *src = TEXEL_ADDR(GLushort, texImage, i, j, k, 1);
>     const GLushort s = (*src << 8) | (*src >> 8); /* byteswap */
> -   texel[RCOMP] = UBYTE_TO_FLOAT( ((s >>  7) & 0xf8) | ((s >> 12) & 0x7) );
> -   texel[GCOMP] = UBYTE_TO_FLOAT( ((s >>  2) & 0xf8) | ((s >>  7) & 0x7) );
> -   texel[BCOMP] = UBYTE_TO_FLOAT( ((s <<  3) & 0xf8) | ((s >>  2) & 0x7) );
> -   texel[ACOMP] = UBYTE_TO_FLOAT( ((s >> 15) & 0x01) * 255 );
> +   texel[RCOMP] = ((s >>  1) & 0x1f) * (1.0F / 31.0F);
> +   texel[GCOMP] = ((s >>  6) & 0x1f) * (1.0F / 31.0F);
> +   texel[BCOMP] = ((s >> 11) & 0x1f) * (1.0F / 31.0F);
> +   texel[ACOMP] = ((s      ) & 0x01) * 1.0F;
>  }
>  
>  
>