[Mesa-dev] [PATCH 17/19] mesa: Add notes about remaining NV_vertex_program code.

[Roland Scheidegger]

Am 10.10.2012 03:06, schrieb Eric Anholt:
> ---
>  src/mesa/main/nvprogram.c   |    4 ++++
>  src/mesa/main/vtxfmt.c      |    2 +-
>  src/mesa/vbo/vbo_exec_api.c |    4 ++++
>  3 files changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/src/mesa/main/nvprogram.c b/src/mesa/main/nvprogram.c
> index 6ad846e3..4b24dde 100644
> --- a/src/mesa/main/nvprogram.c
> +++ b/src/mesa/main/nvprogram.c
> @@ -205,6 +205,10 @@ _mesa_GetProgramStringNV(GLuint id, GLenum pname, GLubyte *program)
>  
>  /**
>   * Get a vertex array attribute pointer.
> + *
> + * While the function first appeared in GL_NV_vertex_program, it's
> + * aliased for use by GL_ARB_vertex_program.
> + *
>   * \note Not compiled into display lists.
>   * \note Called from the GL API dispatcher.
>   */
> diff --git a/src/mesa/main/vtxfmt.c b/src/mesa/main/vtxfmt.c
> index aa6cf28..462cc88 100644
> --- a/src/mesa/main/vtxfmt.c
> +++ b/src/mesa/main/vtxfmt.c
> @@ -135,7 +135,7 @@ install_vtxfmt(struct gl_context *ctx, struct _glapi_table *tab,
>                                                 vfmt->DrawTransformFeedbackStreamInstanced);
>     }
>  
> -   /* GL_NV_vertex_program */
> +   /* Originally for GL_NV_vertex_program, this is also used by dlist.c */
>     if (ctx->API == API_OPENGL) {
>        SET_VertexAttrib1fNV(tab, vfmt->VertexAttrib1fNV);
>        SET_VertexAttrib1fvNV(tab, vfmt->VertexAttrib1fvNV);
> diff --git a/src/mesa/vbo/vbo_exec_api.c b/src/mesa/vbo/vbo_exec_api.c
> index 52b363d..2ddb715 100644
> --- a/src/mesa/vbo/vbo_exec_api.c
> +++ b/src/mesa/vbo/vbo_exec_api.c
> @@ -958,6 +958,10 @@ static void vbo_exec_vtxfmt_init( struct vbo_exec_context *exec )
>        vfmt->VertexAttrib4fvARB = vbo_VertexAttrib4fvARB;
>     }
>  
> +   /* Note that VertexAttrib4fNV is used from dlist.c and api_arrayelt.c so
> +    * they can have a single entrypoint for updating any of the legacy
> +    * attribs.
> +    */
>     vfmt->VertexAttrib1fNV = vbo_VertexAttrib1fNV;
>     vfmt->VertexAttrib1fvNV = vbo_VertexAttrib1fvNV;
>     vfmt->VertexAttrib2fNV = vbo_VertexAttrib2fNV;
>

I think the idea of removing NV_vertex_program is quite good, though I
wonder if these functions shouldn't be renamed and moved instead of
keeping them as is?
Supporting both NV_vertex_program ARB_vertex_program always seems to
have caused headaches (not least because of the different aliasing of
attribs), though for a long time ARB_vertex_program in mesa actually was
code dependent quite a bit on NV_vertex_program.
IIRC celestia used to use NV_vertex_program but it's quite possible it
no longer does.

Roland