It is _very_ improbable that more than 128 partial normals contribute to
one vertex normal. That's why this was deliberately set to 128.
> Here is my code, also I have added some comments for my self to
> understand that is going on.
> But I still do not understand why "128" possible normals used...
> (Code is modified to be compiled with c++)
> (also fix added based on k < 128)
> // bSmooth -> smooth mode enabled 1
> // if bSmooth == 0 => lib3ds_mesh_calculate_normals_ex goes faster with
> quality loose.
>
> void
> lib3ds_mesh_calculate_normals_ex(Lib3dsMesh *mesh, Lib3dsVector
> *normalL, int bSmooth)
> {
> Lib3dsFaces **fl;
> Lib3dsFaces *fa;
> unsigned i,j,k;
>
> if (!mesh->faces)
> {
> return;
> }
>
> fl=(Lib3dsFaces **)calloc(sizeof(Lib3dsFaces*),mesh->points);
> ASSERT(fl);
> fa=(Lib3dsFaces *)calloc(sizeof(Lib3dsFaces),3*mesh->faces);
> ASSERT(fa);
> k=0;
> for (i=0; i<mesh->faces; ++i) {
> Lib3dsFace *f=&mesh->faceL[i];
> for (j=0; j<3; ++j) {
> Lib3dsFaces* l=&fa[k++];
> ASSERT(f->points[j]<mesh->points);
> l->face=f;
> l->next=fl[f->points[j]];
> fl[f->points[j]]=l;
> }
> }
>
> for (i=0; i<mesh->faces; ++i) // e.g. I have sometimes 20 000 faces...
> { //(works to slow)
> Lib3dsFace *f=&mesh->faceL[i];
> Lib3dsVector n; // Can be declared here (change), posible move
> outside of for...
>
>
> for (j=0; j<3; ++j) // face has 3 points (correct? )
> {
> // FIXME: static array needs at least check!!
> Lib3dsVector N[128]; // why 128 ???
> Lib3dsFaces *p;
> int k,l;
> int found;
>
> // f->points[j] -> point index less then mesh->points
> ASSERT(f->points[j]<mesh->points); // right
> if ( f->smoothing && bSmooth)
> {
> lib3ds_vector_zero(n);
> k=0; /// going throught every mesh face point
> for (p=fl[f->points[j]]; p; p=p->next)
> {
> found=0;
> for (l=0; l<k; ++l) // if any dot product was found do
> search
> { // of right normal in the array
> if( l >= 128 )
> {// if would be nice to have predefined TRACE macro
> instead of printf or sprintf
> TRACE("array N overflow: i=%d, j=%d, k=%d\n", i,j,k);
> }
> // |vec1*vect2| -> normal -> check length more than one?
> // why we skip normals less than one? answer:
> // yes -> because we are in the smooth mode
> if (fabs(lib3ds_vector_dot(N[l],
> p->face->normal)-1.0)<1e-5)
> {
> found=1;
> break;
> }
> }
>
> if (bSmooth && !found && k < 128) // k < 128 condition
> added (change)
> { // no dot product found k == 0 init face normal
> // removed condition "f->smoothing", already checked
> before...(change)
> if ( p->face->smoothing )
> {
> lib3ds_vector_add(n,n, p->face->normal);
> lib3ds_vector_copy(N[k], p->face->normal);
> ++k;
> }
> }
> }
> }
> else
> {
> lib3ds_vector_copy(n, f->normal);
> }
> lib3ds_vector_normalize(n);
>
> lib3ds_vector_copy(normalL[3*i+j], n);
> } // end for
> }
>
> free(fa);
> free(fl);
> }
>
> Tomas
>
> Gernot Ziegler wrote:
> > Sorry, I can't run lib3ds due to the stated reasons.
> >
> > So the file works if you apply the fix that you proposed ?
> >
> > I am currently very busy, so my replies might take a while.
> >
> > /Gernot
> >
> >
> >
>
Servus,
Gernot
--
T----------------------------W-E-L-C-O-M-E------------------------------T
O The Austria <=> Sweden <=> Germany <=> Netherlands connection..... H
| http://www.mpi-sb.mpg.de/~gziegler | http://www.lysator.liu.se/~gz E
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