Another test:
I replaced double by integer, for visibility...
typedef struct vec3 {
�������� int data[3];
} vec3;

add a second vec3 to position:

typedef struct position {
�������� int i;
�������� vec3 vec;
�������� vec3 vec2;
} position;

Now in pharo:
Position >> fieldsDesc
"self rebuildFieldAccessors"
������ ^ #(
������ int i;
������ Vec3 vec;
������ Vec3 vec2;
)

The size returned for each stucture is 16 instead of 12 that because of the "8 byte alignment"

Meaning that the "position" structure is corrupted.

With this function:


extern "C" void DLL_EXPORT fillStruct(position *position)
{
������ position -> i = 19;
������ (position -> vec).data[0] = 1;
������ (position -> vec).data[1] = 2;
������ (position -> vec).data[2] = 3;
������ (position -> vec2).data[0] = 1;
������ (position -> vec2).data[1] = 2;
������ (position -> vec2).data[2] = 3;
}

We will get:
position i == 19
position vec at: 1 == 1
position vec2 at: 1 == 2


On Tue, Jul 5, 2016 at 3:12 PM, Ronie Salgado <roniesalg@gmail.com> wrote:
I compiled the DLL using Visual Studio 2015 Community Edition. Later I will check with mingw.

2016-07-05 14:58 GMT+02:00 Merwan Ouddane <merwanouddane@gmail.com>:
Using codeblocks, mine are:

mingw32-g++.exe -m32 -DBUILD_DLL -c main.cpp -o obj\Release\main.o
mingw32-g++.exe -shared -Wl,--output-def=bin\Release\libTest.def -Wl,--out-implib=bin\Release\libTest.a -Wl,--dll�� obj\Release\main.o�� -o bin\Release\Test.dll -s -m32


On Tue, Jul 5, 2016 at 2:52 PM, Merwan Ouddane <merwanouddane@gmail.com> wrote:
I am not moving from another plateform :/

I tried it in pharo 6 and I it didn't work either.

It could be my dll. What is your compilation line for the dll ?

Thanks you,
Merwan

On Tue, Jul 5, 2016 at 2:14 PM, Ronie Salgado <roniesalg@gmail.com> wrote:
Hi Merwan,

I tested this on Pharo 6 and it is working in Windows. However, in 32 bits Window doubles have an 8 byte alignment, unlike Linux where they have a 4 byte alignment.

Can you try doing the following before performing the ffi call in Windows, if you are moving an image from Linux or OS X:

Vec3 rebuildFieldAccessors.
Position rebuildFieldAccessors.

Best regards,
Ronie

2016-07-05 11:11 GMT+02:00 Merwan Ouddane <merwanouddane@gmail.com>:

Hi,

I have an issue whith nested structures.

I made some "dummy" structures in c:


typedef struct vec3 {
�������� double data[3];
} vec3;

typedef struct position {
�������� int i;
�������� vec3 vec;
} position;

And a "dummy" function to fill it:
void fillStruct(position *position)
{
������ position -> i = 19;
������ (position -> vec).data[0] = 1;
������ (position -> vec).data[1] = 2;
������ (position -> vec).data[2] = 3;
}

But I can't make the nested structure work.
The "i" is correctly set to 19 but I have values that doesn't make any sense in the vec3 structure.

In Pharo
I declared the Double3 type for the array inside Vec3:
Double3 := FFITypeArray ofType: 'double' size: 3

Vec3>>fieldsDesc
������ ^ #(
������ Double3 v;
)

And the position:
Position>>fieldsDesc
������ ^ #(
������ int i;
������ Vec3 vec;
)

The ffi call:
^ self ffiCall: #(void fillStruct(Position *position)) module: 'Test.dll'

Sorry for the long / messy mail :p

Any clues ?

Cheers,
Merwan