Re: [Glsdk-devel] The use of anonymous structures

[Jason M. <ko...@gm...>]

Henri Häkkinen wrote:
>
>
> On Sun, Aug 24, 2008 at 4:19 AM, Jason McKesson <ko...@gm... 
> <mailto:ko...@gm...>> wrote:
>
>     Henri Häkkinen wrote:
>>     Does anyone have anything to say on this, please? I am currently
>>     working hard on the GLM and I think we should resolve the issue
>>     of how we actually define the math types.
>     Well, the VC++ compiler issue pretty much ends #2 as a
>     possibility. If #1 doesn't work for you, that leaves #3.
>
>
> Well no, this is not true at all. The VC compiler issues is only about 
> anonymous structures. For example, this generates a warning:
>
> typedef struct GLMvec2f_s {
>   union {
>     GLfloat v[2];
>     struct {
>       GLfloat x, y;
>     }
>   };
> } GLMvec2f;
>
> While this does not:
>
> typedef struct GLMvec2f_s {
>   union {
>     GLfloat v[2];
>     struct GLMvec2fcoords_s {
>       GLfloat x, y;
>     }
>   };
> } GLMvec2f;
>
Admittedly it's been a while since I last used pure C, but if I'm 
reading that right, to access the x or y members, I would need:

GLMvec2f someValue;

someValue.GLMvec3fcoords_s.x = 0.5f

This is a pretty clear violation of design goal #2: Simplicity. And if 
the inner struct can't be accessed with a simple ".x", then what's the 
point in having it at all?