Problems with GB_ATTRIB_STRING

[rjpieke]

I have a simple Add SOP (which creates a single point) followed by an AttribCreate SOP. I want to attach a string attribute to the point, which seems to be no problem (I set the type to string and, when I open the spreadsheet, I see the value). This then plugs into a custom SOP, which can not seem to find the attribute. The code is below:

int offsetStr = myGDP->findPointAttrib( "ccn", GB_ATTRIB_STRING );  // always returns -1
int offsetFlt = myGDP->findPointAttrib( "ccn", GB_ATTRIB_FLOAT );   // returns -1 or #

When I search for the type by GB_ATTRIB_STRING, I ALWAYS get -1. When I set the type to float in the AttribCreate, and then search by GB_ATTRIB_FLOAT, I get a proper offset.

What am I missing?

Thanks in advance!

[crunch]

I have a simple Add SOP (which creates a single point) followed by an AttribCreate SOP. I want to attach a string attribute to the point, which seems to be no problem (I set the type to string and, when I open the spreadsheet, I see the value). This then plugs into a custom SOP, which can not seem to find the attribute. The code is below:

int offsetStr = myGDP->findPointAttrib( "ccn", GB_ATTRIB_STRING );  // always returns -1
int offsetFlt = myGDP->findPointAttrib( "ccn", GB_ATTRIB_FLOAT );   // returns -1 or #

When I search for the type by GB_ATTRIB_STRING, I ALWAYS get -1. When I set the type to float in the AttribCreate, and then search by GB_ATTRIB_FLOAT, I get a proper offset.

What am I missing?

Thanks in advance!

16155[/snapback]

I believe that GB_ATTRIB_STRING has been deprecated in favour of GB_ATTRIB_INDEX.

void
addString(GU_Detail *gdp)
{
    GB_Attribute	*attrib;
    int    minus_one = -1;
    int    i, handle;
    int    string_id, *avalue;
    GEO_Primitive	*prim;
    char   value[32];

    attrib = gdp->addPrimAttrib("cnn", sizeof(int), GB_ATTRIB_INDEX,
    (void *)&minus_one);
    handle = gdp->findPrimAttrib("cnn", sizeof(int), GB_ATTRIB_INDEX);
    if (handle >= 0)
    {
	for (i = 0; i < gdp->primitives().entries(); i++)
	{
     // Get a pointer to the primitive's attribute data
     avalue = gdp->primitives()(i)->getAttribData(handle);

     // Set the value of the string
     sprintf(value, "value%d", i%10);

     // Add the string value to the attribute container and set
     // the primitive's attribute value to the appropriate
     // index.
     *avalue = attrib->addIndex(value);
	}
    }
}

Something like this. As well, you might have to access it using the

prims() or points() function (which return string values).

Hope this helps,

[rjpieke]

I believe that GB_ATTRIB_STRING has been deprecated in favour of GB_ATTRIB_INDEX.

Hope this helps,

16164[/snapback]

Aha! Yes, indeed ... if I search for my string attribute via GB_ATTRIB_INDEX, I get an offset. Unfortunately, this now leads me to have to ask two more questions:

1) How do I access the data? I'm going through points().head()->getAttribData( offset ) ... but I'm not sure what I'm being returned. I was hoping it was the character string, but when I dereference the pointer, the first value is 0.

2) Does it actually say somewhere that GB_ATTRIB_STRING "isn't used any more"?

Thanks!

[crunch]

Aha! Yes, indeed ... if I search for my string attribute via GB_ATTRIB_INDEX, I get an offset.  Unfortunately, this now leads me to have to ask two more questions:

1) How do I access the data? I'm going through points().head()->getAttribData( offset ) ... but I'm not sure what I'm being returned. I was hoping it was the character string, but when I dereference the pointer, the first value is 0.

2) Does it actually say somewhere that GB_ATTRIB_STRING "isn't used any more"?

Thanks!

16167[/snapback]

The GB_Attribute class holds a list of strings. The integer value stored with the attribute is an index into those strings. You have to ask the GB_Attribute what the string is.

   const char *string = attrib->getIndex(integer_attribute_value);

[rjpieke]

The GB_Attribute class holds a list of strings.  The integer value stored with the attribute is an index into those strings.  You have to ask the GB_Attribute what the string is.

   const char *string = attrib->getIndex(integer_attribute_value);

16171[/snapback]

Ok, that's fine ... but how do I get a GB_Attribute from a GEO_Point or a GU_Detail?

[Guest xionmark]

2) Does it actually say somewhere that GB_ATTRIB_STRING "isn't used any more"?

I haven't seen anything that says it's not used anymore ... however, I always get a -1 returned as opposed to GB_ATTRIB_INDEX always returning the "correct" offset.

--Mark

[Guest xionmark]

Ok, that's fine ... but how do I get a GB_Attribute from a GEO_Point or a GU_Detail?

16172[/snapback]

Well, I did something like this:

GB_Attribute * myGB_Attr = gdp->attribs().find("sd_obj_tex_fname");
        obj_tex_fname = gdp->findAttrib("sd_obj_tex_fname", GB_ATTRIB_INDEX);


if(myGB_Attr != NULL) {
    cout << "getType: " << myGB_Attr->getType() << endl;
    cout << "getTypeInfo: " << myGB_Attr->getTypeInfo() << endl;
    cout << "getName: " << myGB_Attr->getName() << endl;
    cout << "getSize: " << myGB_Attr->getSize() << endl;
    cout << "getAllocSize: " << myGB_Attr->getAllocSize() << endl;
    cout << "getIndex: " << myGB_Attr->getIndex("sd_obj_tex_fname") << endl;
    cout << "getIndex: " << myGB_Attr->getIndex(obj_tex_fname) << endl;
    cout << "getIndexSize: " << myGB_Attr->getIndexSize() << endl;
}

But the getIndex(obj_tex_fname) call segv's. The getIndex("sd_obj_tex_fname") call always returns a -1 ... so I'm still not able to grab the string from the attributes.

By the way, is it a UT_String or cinst char * that gets returned from getAttribData()?

--Mark

[Guest xionmark]

Ok, that's fine ... but how do I get a GB_Attribute from a GEO_Point or a GU_Detail?

16172[/snapback]

Well, I did something like this:

GB_Attribute * myGB_Attr = gdp->attribs().find("sd_obj_tex_fname");
        obj_tex_fname = gdp->findAttrib("sd_obj_tex_fname", GB_ATTRIB_INDEX);


if(myGB_Attr != NULL) {
    cout << "getType: " << myGB_Attr->getType() << endl;
    cout << "getTypeInfo: " << myGB_Attr->getTypeInfo() << endl;
    cout << "getName: " << myGB_Attr->getName() << endl;
    cout << "getSize: " << myGB_Attr->getSize() << endl;
    cout << "getAllocSize: " << myGB_Attr->getAllocSize() << endl;
    cout << "getIndex: " << myGB_Attr->getIndex("sd_obj_tex_fname") << endl;
    cout << "getIndex: " << myGB_Attr->getIndex(obj_tex_fname) << endl;
    cout << "getIndexSize: " << myGB_Attr->getIndexSize() << endl;
}

But the getIndex(obj_tex_fname) call always segv's. The getIndex("sd_obj_tex_fname") call always returns a -1 ... so I'm still not able to grab the string from the attributes.

By the way, is it a UT_String or const char * that gets returned from getAttribData() when trying to retrieve a string attribute?

--Mark

[Guest xionmark]

Woohoo!

OK, I got some results, here's the hacked code (i.e. needs cleanup but works):

=====================================

const char * obj_tex_fname_str;

obj_tex_fname = gdp->findAttribute("sd_obj_tex_fname", sizeof(int), GB_ATTRIB_INDEX, GEO_DETAIL_DICT);
cout << "obj_tex_fname: " << obj_tex_fname << endl;

GB_Attribute * myGB_Attr = gdp->attribs().find("sd_obj_tex_fname", GB_ATTRIB_INDEX);

if(myGB_Attr != NULL) {
    int *p_obj_tex_fname_idx = ((int *)gdp->attribs().getAttribData(obj_tex_fname));
    cout << "obj_tex_fname_idx: " << *p_obj_tex_fname_idx << endl;
    obj_tex_fname_str = myGB_Attr->getIndex(*p_obj_tex_fname_idx);
    cout << "obj_tex_fname_str: " << obj_tex_fname_str << endl;
}

--Mark

[rjpieke]

Woohoo!

OK, I got some results, here's the hacked code (i.e. needs cleanup but works):

=====================================

const char * obj_tex_fname_str;

obj_tex_fname = gdp->findAttribute("sd_obj_tex_fname", sizeof(int), GB_ATTRIB_INDEX, GEO_DETAIL_DICT);
cout << "obj_tex_fname: " << obj_tex_fname << endl;

GB_Attribute * myGB_Attr = gdp->attribs().find("sd_obj_tex_fname", GB_ATTRIB_INDEX);

if(myGB_Attr != NULL) {
    int *p_obj_tex_fname_idx = ((int *)gdp->attribs().getAttribData(obj_tex_fname));
    cout << "obj_tex_fname_idx: " << *p_obj_tex_fname_idx << endl;
    obj_tex_fname_str = myGB_Attr->getIndex(*p_obj_tex_fname_idx);
    cout << "obj_tex_fname_str: " << obj_tex_fname_str << endl;
}

--Mark

16231[/snapback]

Looks great, but do you know how to extend this to get string attributes on points (i.e., not detail attributes)?

[Guest xionmark]

Looks great, but do you know how to extend this to get string attributes on points (i.e., not detail attributes)?

16236[/snapback]

Nope, not yet. But will try later today if I get the time.

--Mark

[rjpieke]

Nope, not yet.  But will try later today if I get the time.

--Mark

16237[/snapback]

Aha! Issue resolved (kudos to Jeff Lait)!

int myOffset = myGDP->findPointAttrib( "ccn", GB_ATTRIB_INDEX );
const GEO_Point *point = myGDP->points().head();
for( int i = 0; point; point = myGDP->points().next( point ), i++ )
{
  GB_Attribute *myAttr =
    myGDP->pointAttribs().find( "ccn", GB_ATTRIB_INDEX );
  int myIndex =
    *( int* )point->getAttribData( myOffset );
  const char* myString =
    cacheNameAttr->getIndex( cacheNameIndex ) );
  // DO SOMETHING INTERESTING WITH myString
}

[Nasyrov]

int test = gdp->addPointAttrib("tex", sizeof(UT_String), GB_ATTRIB_INDEX, 0);

int texID = gdp->findPointAttrib("tex", GB_ATTRIB_INDEX);

GB_Attribute *texAttr = gdp->pointAttribs().find("tex", GB_ATTRIB_INDEX);

string tex = "Mandril.pic"

FOR_ALL_GPOINTS(gdp, ppt)

{

int texIndex = *(int*)ppt->getAttribData(texID);

const char *texString = texAttr->getIndex(texIndex);

texString = tex.c_str();

}

FOR_ALL_GPOINTS(gdp, ppt)

{

int texIndex = *(int*)ppt->getAttribData(texID);

UT_String pTex = texAttr->getIndex(texIndex);

cout<<pTex<<endl;

}

But the result is ""

Does anyone know why it so?

Thanks

Edited October 28, 2008 by Nasyrov