[Piglit] [PATCH 03/15] gl-3.2/adj-prims: fix expected vertex order for triangle strips with adjacency

[Brian Paul]

For 3&4,
Reviewed-by: Brian Paul <brianp at vmware.com>
Tested-by: Brian Paul <brianp at vmware.com>  (on NVIDIA)


On 03/26/2018 05:32 PM, Marek Olšák wrote:
> From: Nicolai Hähnle <nicolai.haehnle at amd.com>
> 
> The first two vertices are swapped for triangle strips with adjacency; see
> Table 10.1 of the OpenGL 4.5 (Compatibility Profile) spec.
> ---
>   tests/spec/gl-3.2/adj-prims.c | 18 +++++++++++++-----
>   1 file changed, 13 insertions(+), 5 deletions(-)
> 
> diff --git a/tests/spec/gl-3.2/adj-prims.c b/tests/spec/gl-3.2/adj-prims.c
> index 794ab3dc9..f4479c708 100644
> --- a/tests/spec/gl-3.2/adj-prims.c
> +++ b/tests/spec/gl-3.2/adj-prims.c
> @@ -167,23 +167,26 @@ provoking_vertex_index(GLenum prim_mode, GLenum pv_mode, unsigned prim_index)
>   		if (pv_mode == GL_FIRST_VERTEX_CONVENTION)
>   			return prim_index + 1;
>   		else
>   			return prim_index + 2;
>   	case GL_TRIANGLES_ADJACENCY:
>   		if (pv_mode == GL_FIRST_VERTEX_CONVENTION)
>   			return prim_index * 6 + 0;
>   		else
>   			return prim_index * 6 + 4;
>   	case GL_TRIANGLE_STRIP_ADJACENCY:
> -		if (pv_mode == GL_FIRST_VERTEX_CONVENTION)
> -			return prim_index * 2;
> -		else
> +		if (pv_mode == GL_FIRST_VERTEX_CONVENTION) {
> +			if (prim_index & 1)
> +				return prim_index * 2 + 2;
> +			else
> +				return prim_index * 2;
> +		} else
>   			return prim_index * 2 + 4;
>   	default:
>   		assert(!"Unexpected prim_mode");
>   		return 0;
>   	}
>   }
>   
>   
>   /**
>    * Given a primitive type and a primitive (line/triangle) index, return
> @@ -206,22 +209,27 @@ compute_probe_location(GLenum prim_mode, unsigned prim_index,
>   		i0 = prim_index + 1;
>   		i1 = prim_index + 2;
>   		break;
>   	case GL_TRIANGLES_ADJACENCY:
>   		i0 = prim_index * 6 + 0;
>   		i1 = prim_index * 6 + 2;
>   		if (polygon_mode != GL_LINE)
>   			i2 = prim_index * 6 + 4;
>   		break;
>   	case GL_TRIANGLE_STRIP_ADJACENCY:
> -		i0 = prim_index * 2;
> -		i1 = prim_index * 2 + 2;
> +		if (prim_index & 1) {
> +			i0 = prim_index * 2;
> +			i1 = prim_index * 2 + 2;
> +		} else {
> +			i0 = prim_index * 2 + 2;
> +			i1 = prim_index * 2;
> +		}
>   		if (polygon_mode != GL_LINE)
>   			i2 = prim_index * 2 + 4;
>   		break;
>   	default:
>   		assert(!"Unexpected prim_mode");
>   		*x = *y = 0;
>   		return;
>   	}
>   
>   	/* average of 2 or 3 points */
>