On 02/10/2014 05:29 PM, Anuj Phogat wrote:
> GLSL 1.50 spec says:
> "If gl_FragCoord is redeclared in any fragment shader in a program,
> it must be redeclared in all the fragment shaders in that
> program that have a static use gl_FragCoord. All redeclarations of
> gl_FragCoord in all fragment shaders in a single program must
> have the same set of qualifiers."
>
> This patch makes the glsl compiler to generate an error if we have a
> fragment shader defined with conflicting layout qualifier declarations
> for gl_FragCoord. For example:
>
> layout(origin_upper_left, pixel_center_integer) in vec4 gl_FragCoord;
> layout(pixel_center_integer) in vec4 gl_FragCoord;
> void main()
> {
> gl_FragColor = gl_FragCoord.xyzz;
> }
>
> Cc: <mesa-sta...@lists.freedesktop.org>
> Signed-off-by: Anuj Phogat <anuj.pho...@gmail.com>
> ---
> src/glsl/ast_to_hir.cpp | 39 +++++++++++++++++++++++++++++++++++++++
> src/glsl/glsl_parser_extras.cpp | 3 +++
> src/glsl/glsl_parser_extras.h | 10 ++++++++++
> 3 files changed, 52 insertions(+)
>
> diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp
> index c89a26b..7d7d89b 100644
> --- a/src/glsl/ast_to_hir.cpp
> +++ b/src/glsl/ast_to_hir.cpp
> @@ -2374,6 +2374,45 @@ apply_type_qualifier_to_variable(const struct
> ast_type_qualifier *qual,
> qual_string);
> }
>
> + /* Make sure all gl_FragCoord redeclarations specify the same layout
> + * qualifier type.
> + */
> + bool conflicting_pixel_center_integer =
> + state->fs_pixel_center_integer &&
> + !qual->flags.q.pixel_center_integer;
> +
> + bool conflicting_origin_upper_left =
> + state->fs_origin_upper_left &&
> + !qual->flags.q.origin_upper_left;
I don't think this catches all the cases. What about
layout(origin_upper_left ) in vec4 gl_FragCoord;
layout(origin_upper_left, pixel_center_integer) in vec4 gl_FragCoord;
> +
> + if (conflicting_pixel_center_integer || conflicting_origin_upper_left) {
> + const char *const qual_string =
> + (conflicting_pixel_center_integer && conflicting_origin_upper_left)
> ?
> + "pixel_center_integer, origin_upper_left" :
> + (conflicting_pixel_center_integer ?
> + "origin_upper_left" : "pixel_center_integer");
> +
> + const char *const state_string =
> + (state->fs_pixel_center_integer &&
> + state->fs_origin_upper_left) ?
> + "pixel_center_integer, origin_upper_left" :
> + (state->fs_origin_upper_left ?
> + "origin_upper_left" : "pixel_center_integer");
> +
> + _mesa_glsl_error(loc, state,
> + "different layout qualifiers were specified with "
> + "`gl_FragCoord' (%s) and (%s) "
> + "redeclare fragment shader input `gl_FragCoord'",
> + state_string,
> + qual_string);
> + }
> +
> + if (qual->flags.q.pixel_center_integer)
> + state->fs_pixel_center_integer = true;
> +
> + if (qual->flags.q.origin_upper_left)
> + state->fs_origin_upper_left = true;
> +
> if (qual->flags.q.explicit_location) {
> validate_explicit_location(qual, var, state, loc);
> } else if (qual->flags.q.explicit_index) {
> diff --git a/src/glsl/glsl_parser_extras.cpp b/src/glsl/glsl_parser_extras.cpp
> index b822d22..b06337e 100644
> --- a/src/glsl/glsl_parser_extras.cpp
> +++ b/src/glsl/glsl_parser_extras.cpp
> @@ -193,6 +193,9 @@ _mesa_glsl_parse_state::_mesa_glsl_parse_state(struct
> gl_context *_ctx,
> this->default_uniform_qualifier->flags.q.shared = 1;
> this->default_uniform_qualifier->flags.q.column_major = 1;
>
> + this->fs_origin_upper_left = false;
> + this->fs_pixel_center_integer = false;
> +
> this->gs_input_prim_type_specified = false;
> this->gs_input_prim_type = GL_POINTS;
> this->gs_input_size = 0;
> diff --git a/src/glsl/glsl_parser_extras.h b/src/glsl/glsl_parser_extras.h
> index 7d66147..674dae5 100644
> --- a/src/glsl/glsl_parser_extras.h
> +++ b/src/glsl/glsl_parser_extras.h
> @@ -182,6 +182,16 @@ struct _mesa_glsl_parse_state {
> struct ast_type_qualifier *default_uniform_qualifier;
>
> /**
> + * True if a fragment shader has an input layout for redeclaring the
> + * built-in variable gl_FragCoord.
> + *
> + * Note: this value is computed at ast_to_hir time rather than at parse
> + * time.
> + */
> + bool fs_origin_upper_left;
> + bool fs_pixel_center_integer;
> +
> + /**
> * True if a geometry shader input primitive type was specified using a
> * layout directive.
> *
>
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/mesa-dev
