put geom wrapper struct inside same #ifs as geom function

[PiMaker]

Fixes a miscompilation for code like this:

#if defined(FOO)
[maxvertexcount(3)]
void geom(...)
{
    ...
}
#endif

#if defined(BAR)
[maxvertexcount(3)]
void geom(...)
{
    ...
}
#endif

Previously the wrapper structs would end up outside the #if defined(FOO) defines unnecessarily (they aren't needed when the corresponding function is not compiled anyway). This leads to a duplicate struct definition regardless of defines:

struct geometryInputWrapper
{
    ...
}
#if defined(FOO)
[maxvertexcount(3)]
void geom(...)
{
    ...
}
#endif

struct geometryInputWrapper        // <- duplicate definition!
{
    ...
}
#if defined(BAR)
[maxvertexcount(3)]
void geom(...)
{
    ...
}
#endif

The original code is perfectly valid though, as long as FOO and BAR are exclusive keywords.

This fix moves the struct definition below the #if which makes them exclusive to each other similar to the function itself.

Alternative Fixes

The reason for searching until the top-most s.StartsWith("[") is obvious, but I wasn't sure if there was a case where the search for s.StartsWith("#") was needed too, so I restricted it to only exclude conditionals.

An alternative solution would be to rename the structs, e.g. encode dummyLineIndex (function name wouldn't work as can be the same) into it.

[d4rkc0d3r]

but I wasn't sure if there was a case where the search for s.StartsWith("#") was needed too

it is absolutely needed. an example would be:

#if defined(FOO)
[maxvertexcount(3)]
#else
[maxvertexcount(6)]
#endif
void geom(...)
{

So this would need the alternate solution with differently named wrapper structs.

[PiMaker]

Of course it's not that simple, should have went with my gut on the renaming solution 🤦🏻

Changed to that approach in fccfdd0 and confirmed it still works on my test shader.