[Piglit] [PATCH] teximage-colors: accept -127 instead of -128 for exact snorm up/download

[Roland Scheidegger]

ping?

Am 08.01.2018 um 01:20 schrieb sroland at vmware.com:
> From: Roland Scheidegger <sroland at vmware.com>
> 
> -128 and -127 represent exactly the same value (-1.0) for snorm8 values,
> as do -32768/-32767 for snorm16. Therefore it seems quite reasonable that an
> implementation would return the other representation (in particular r600 will
> do this with a blit, and the snorm->float->snorm conversion implied by this
> will never return the -128/-32768 values).
> ---
>  tests/texturing/teximage-colors.c | 39 +++++++++++++++++++++++++++++++++++----
>  1 file changed, 35 insertions(+), 4 deletions(-)
> 
> diff --git a/tests/texturing/teximage-colors.c b/tests/texturing/teximage-colors.c
> index de2024644..61a3c5d15 100644
> --- a/tests/texturing/teximage-colors.c
> +++ b/tests/texturing/teximage-colors.c
> @@ -833,10 +833,41 @@ test_exact()
>  		      observed);
>  	pass &= piglit_check_gl_error(GL_NO_ERROR);
>  
> -	for (i = 0; i < texture_size; ++i)
> -		pass &= memcmp(&data[i * texture_size * Bpp],
> -			       &observed[i * tex_width * Bpp],
> -			       texture_size * Bpp) == 0;
> +	/*
> +	 * For snorm formats, -127/-128 and -32767/-32768 represent the exact
> +	 * same value (-1.0). Therefore, it is quite reasonable to expect
> +	 * an implementation could return the other representation.
> +	 * (We'll assume it will happen only one way the other way seems rather
> +	 * unlikely.)
> +	 */
> +	if (format->data_type == GL_BYTE) {
> +		int j;
> +		for (j = 0; j < texture_size; ++j) {
> +			for (i = 0; i < tex_width * channels; i++) {
> +				if (!(data[i] == observed[i] ||
> +				      (data[i] == 128 && observed[i] == 129))) {
> +					pass = GL_FALSE;
> +				}
> +			}
> +		}
> +	} else if (format->data_type == GL_SHORT) {
> +		int j;
> +		for (j = 0; j < texture_size; ++j) {
> +			for (i = 0; i < tex_width * channels; i++) {
> +				GLshort datas = ((GLshort *)data)[i];
> +				GLshort obss = ((GLshort *)observed)[i];
> +				if (!(datas == obss ||
> +				      (datas == -32768 && obss == -32767))) {
> +					pass = GL_FALSE;
> +				}
> +			}
> +		}
> +	} else {
> +		for (i = 0; i < texture_size; ++i)
> +			pass &= memcmp(&data[i * texture_size * Bpp],
> +				&observed[i * tex_width * Bpp],
> +				texture_size * Bpp) == 0;
> +	}
>  
>  	free(observed);
>  	free(tmp_float);
>