Hey,

I was writing a .blend parser for a new game engine, but I ran into a little problem. I am able to find the structures for the things I need and associate them with a pointer, but the problem comes when trying to find the address of another pointer in that structure.

Here is an example of what I mean:

Code:

/* snippet from blend_sdna.h */ #define SDNA_MESH         52 typedef struct sdna_mesh_s {    sdna_id_t id;    sdna_boundbox_t *bb;    sdna_listbase_t effect;    sdna_ipo_t *ipo;    sdna_key_t *key;    sdna_material_t **mat;    sdna_mface_t *mface;    sdna_mtface_t *mtface;    sdna_tface_t *tface;    sdna_mvert_t *mvert;    sdna_medge_t *medge;    sdna_mdeformvert_t *dvert;    sdna_mcol_t *mcol;    sdna_msticky_t *msticky;    sdna_mesh_t *texcomesh;    sdna_mselect_t *mselect;    sdna_customdata_t vdata;    sdna_customdata_t edata;    sdna_customdata_t fdata;    int totvert;    int totedge;    int totface;    int totselect;    int act_face;    int texflag;    float loc[3];    float size[3];    float rot[3];    float cubemapsize;    float pad;    short smoothresh;    short flag;    short subdiv;    short subdivr;    short totcol;    short subsurftype;    void *mr;      // sdna_multires_t *mr;    void *pv;      // sdna_partialvisibility_t *pv;    void *vnode; } sdna_mesh_t; /* snippet from main.cpp */ .... some more code ..... blend_file_t blend; block_t block; if(!blend_load("test.blend", &blend)) // custom function {    std::cout << "Could not find test.blend";    return 0; } do {    blend_readblock(&block, &blend); } while(block.header.SDNA_index != SDNA_MESH); sdna_mesh_t *mesh = (sdna_mesh_t *)block.code; std::cout << mesh->id.name; // prints out MECube just fine.

The above works just fine. the problem is when I try to get another pointer inside the sdna_mesh_t struct (such as mesh->key->elemstr).

How would I go about mapping mesh->key to the correct location in the blend file?

Sorry about this question (I am sure it has been asked many times before), but I am on a deadline and need to focus on more than just this.

Any help would be much appreciated!

Thank you!
Christian Modas

Actually I think I just figured it out.

Code:

blend_file_t *blend = new blend_file_t;    block_t block;    if(!blend_open("test.blend", blend))    {       std::cout << "Could not load test.blend!";       return 0;    }    std::cout << "Pointer Size: " << blend->header.pointer_size << "\nEndianness: " << blend->header.endianness << "\nBlender Version: " << blend->header.version_number << "\n\n";        blend_skipblocks(6, blend);    do    {       blend_readblock(&block, blend);    } while(block.header.SDNA_index != SDNA_MESH);    sdna_mesh_t *mesh = (sdna_mesh_t *)block.code;    do    {       blend_readblock(&block, blend);    } while(block.header.SDNA_index != SDNA_MVERT && block.header.old_memory_address != mesh->mvert);    mesh->mvert = (sdna_mvert_t *)block.code;    std::cout << mesh->mvert->co[0];    blend_close(blend);

I'll post the code in case anybody else needs help. Its not near complete to read everything, but I just needed something to convert .blend files into other formats (levels, models, animations, ect.).

http://www.megafileupload.com/en/file/328028/blend-reader-zip.html

sounds like the reason I needed to know the file format.

I'm working on a model converter of my own to support a variety of file formats based on the plugins
(like winamp)
_________________

The Crystal Space project did some work (C++, iirc) on a reader for .blend files. The Blender file format is a little tricky to deal with because:

* .blend files are designed to be forward & backward compatible betweenversions

* the .blend format was not designed as a file interchange format and is essentially a memory dump from a running instance of Blender

* the structure can (and does!) change between Blender versions to support new features.

The Blender DNA stuff is your friend here.

>.>
are you telling me that, or him?
cause I think you've already told me that...
if not you, then I know somebody has >_>

is there any documentation on blender DNA that's not in C++??
_________________

I used these two pages for references:

http://www.blender.org/development/architecture/blender-file-format/
http://www.atmind.nl/blender/blender-sdna.html

Actually all the stuff from the last link was using blender version 2.49. I would like to use version 2.59. I think the SDNA index is changed for the objects. Does anybody know how one would go about finding this? I think its somewhere stored in the blend file, but I really would just like some numbers.

well once again, the mystery has been solved. Here is the solution if anybody else is having the same problem:

Quote:

Hi Cristian, The script is inside Blenders source tree. To be exact see https://svn.blender.org/svnroot/bf-blender/trunk/blender/doc/blender_file_format/ Best regards, Jeroen - At Mind B.V. -

YES!
thank you

just in the exact language I can read XDD
_________________

FakeMajor wrote:

Actually I think I just figured it out. ... I'll post the code in case anybody else needs help. Its not near complete to read everything, but I just needed something to convert .blend files into other formats (levels, models, animations, ect.). http://www.megafileupload.com/en/file/328028/blend-reader-zip.html

i need really help i completely parsed the .blend file but now i have problems to interpret the data.
can u please send me your code?

Quote:

marik89 Posted: Thu Dec 08, 2011 9:26 pm Post subject: FakeMajor wrote: Actually I think I just figured it out. ... I'll post the code in case anybody else needs help. Its not near complete to read everything, but I just needed something to convert .blend files into other formats (levels, models, animations, ect.). http://www.megafileupload.com/en/file/328028/blend-reader-zip.html i need really help i completely parsed the .blend file but now i have problems to interpret the data. can u please send me your code?

Do you still need the code? its been a while since this was posted

Have a look at this code https://github.com/ldo/blendparser.

FakeMajor wrote:

Quote: marik89 Posted: Thu Dec 08, 2011 9:26 pm Post subject: FakeMajor wrote: Actually I think I just figured it out. ... I'll post the code in case anybody else needs help. Its not near complete to read everything, but I just needed something to convert .blend files into other formats (levels, models, animations, ect.). http://www.megafileupload.com/en/file/328028/blend-reader-zip.html i need really help i completely parsed the .blend file but now i have problems to interpret the data. can u please send me your code? Do you still need the code? its been a while since this was posted

My Importer is running well but only with 32bit files.
Does your code Support 64Bit files?
If Yes i still need the code.