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[ag0aep6g via Digitalmars-d-learn]

On Sunday, 26 March 2017 at 10:34:21 UTC, Dlearner wrote:
> I came back to this project and realised my mistakes (Importer 
> is a class for the C++ API, and we're using the C API).
> So I fixed all my errors, but now I get an access violation.
> As far as I can tell, it seems to be an issue with 
> `aiGetMaterialTexture`.  It is meant to return an aiString with 
> a filename (default value of "$texture.png"), I believe.  But I 
> get:
>
> aiString(13, x"67 6C 61 73 73 5F 64 69 66 2E 70 6E 67 00 FF FF 
> FF ... FF"c)
> [shortened for brevity]

The data is "glass_dif.png", followed by a null terminator, 
followed by a bunch of 0xFFs. 13 is the length of 
"glass_dif.png". Judging from the definition of aiString [1], the 
0xFFs are just unused space. So, this looks good.

> I'm meant to add this on to a directory string so I can load an 
> image, but obviously this wouldn't work.

To convert an aiString to a D string, it should be possible to 
slice the data with the length:

     aiString x;
     const(char)[] y = x.data[0 .. x.length];

You have to be cautiots of lifetime requirements, of course. If 
needed, you can make a copy with dup (mutable copy) or idup 
(immutable copy):

     const(char)[] y = x.data[0 .. x.length].dup;
     string z = x.data[0 .. x.length].idup;


[1] http://www.assimp.org/lib_html/structai_string.html