[Mesa-dev] [PATCH 3/6] mesa: Add support for GL_NV_fill_rectangle

[Ilia Mirkin]

On Thu, Mar 23, 2017 at 11:27 AM, Lyude <lyude at redhat.com> wrote:
> Since we don't have the bits required to support this in OpenGLES yet,
> this only enables support for OpenGL 4.3.

I think the reference to GL 4.3 isn't quite right. Probably meant to
say "Desktop OpenGL". Also, one usually writes it as "OpenGL ES", with
the space.

>
> Signed-off-by: Lyude <lyude at redhat.com>
> ---
>  src/mesa/main/api_validate.c     | 13 +++++++++++++
>  src/mesa/main/extensions_table.h |  1 +
>  src/mesa/main/mtypes.h           |  1 +
>  src/mesa/main/polygon.c          | 15 +++++++++++++--
>  4 files changed, 28 insertions(+), 2 deletions(-)
>
> diff --git a/src/mesa/main/api_validate.c b/src/mesa/main/api_validate.c
> index 44d164a..bec6407 100644
> --- a/src/mesa/main/api_validate.c
> +++ b/src/mesa/main/api_validate.c
> @@ -609,6 +609,19 @@ _mesa_valid_prim_mode(struct gl_context *ctx, GLenum mode, const char *name)
>        }
>     }
>
> +   /* From the GL_NV_fill_rectangle spec:
> +    *
> +    * An INVALID_OPERATION error is generated by Begin or any Draw command if
> +    * only one of the front and back polygon mode is FILL_RECTANGLE_NV.
> +    */
> +   if ((ctx->Polygon.FrontMode == GL_FILL_RECTANGLE_NV) !=
> +       (ctx->Polygon.BackMode == GL_FILL_RECTANGLE_NV)) {
> +      _mesa_error(ctx, GL_INVALID_OPERATION,
> +                  "GL_NV_fill_rectangle can only be used on both the front "
> +                  "and back polygon mode, not one or the other");
> +      return GL_FALSE;
> +   }

Why is this in the valid_prim_mode check? I don't think this has much
to do with the prim mode. (As an aside, what's supposed to happen if
you draw lines with this polygon mode set... I'm guessing nothing.
Would be good to have a test for that.) Either a separate function or
_mesa_valid_to_render() seem like better candidates.

> +
>     return GL_TRUE;
>  }
>
> diff --git a/src/mesa/main/extensions_table.h b/src/mesa/main/extensions_table.h
> index ec71791..f2eac2b 100644
> --- a/src/mesa/main/extensions_table.h
> +++ b/src/mesa/main/extensions_table.h
> @@ -320,6 +320,7 @@ EXT(NV_conditional_render                   , NV_conditional_render
>  EXT(NV_depth_clamp                          , ARB_depth_clamp                        , GLL, GLC,  x ,  x , 2001)
>  EXT(NV_draw_buffers                         , dummy_true                             ,  x ,  x ,  x , ES2, 2011)
>  EXT(NV_fbo_color_attachments                , dummy_true                             ,  x ,  x ,  x , ES2, 2010)
> +EXT(NV_fill_rectangle                       , NV_fill_rectangle                      , GLL, GLC,  x ,  x , 2015)
>  EXT(NV_fog_distance                         , NV_fog_distance                        , GLL,  x ,  x ,  x , 2001)
>  EXT(NV_image_formats                        , ARB_shader_image_load_store            ,  x ,  x ,  x ,  31, 2014)
>  EXT(NV_light_max_exponent                   , dummy_true                             , GLL,  x ,  x ,  x , 1999)
> diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
> index be78b96..88b8e2b 100644
> --- a/src/mesa/main/mtypes.h
> +++ b/src/mesa/main/mtypes.h
> @@ -4016,6 +4016,7 @@ struct gl_extensions
>     GLboolean MESA_shader_integer_functions;
>     GLboolean MESA_ycbcr_texture;
>     GLboolean NV_conditional_render;
> +   GLboolean NV_fill_rectangle;
>     GLboolean NV_fog_distance;
>     GLboolean NV_point_sprite;
>     GLboolean NV_primitive_restart;
> diff --git a/src/mesa/main/polygon.c b/src/mesa/main/polygon.c
> index 60af88f..2b57f36 100644
> --- a/src/mesa/main/polygon.c
> +++ b/src/mesa/main/polygon.c
> @@ -131,8 +131,19 @@ _mesa_PolygonMode( GLenum face, GLenum mode )
>                    _mesa_enum_to_string(face),
>                    _mesa_enum_to_string(mode));
>
> -   if (mode!=GL_POINT && mode!=GL_LINE && mode!=GL_FILL) {
> -      _mesa_error( ctx, GL_INVALID_ENUM, "glPolygonMode(mode)" );
> +   switch (mode) {
> +   case GL_POINT:
> +   case GL_LINE:
> +   case GL_FILL:
> +      break;
> +   case GL_FILL_RECTANGLE_NV:
> +      if (!ctx->Extensions.NV_fill_rectangle) {
> +         _mesa_error(ctx, GL_INVALID_ENUM, "glPolygonMode(mode)");
> +         return;
> +      }

Or you could be all sneaky-like and do something like

if (ctx->Extensions.NV_fill_rectangle)
  break;
/* fallthrough */

> +      break;
> +   default:
> +      _mesa_error(ctx, GL_INVALID_ENUM, "glPolygonMode(mode)");
>        return;
>     }
>
> --
> 2.9.3
>