int
r_face( /* convert a face */
int ac,
char **av
)
{
static int nfaces;
int myi = invert;
char *mat;
register int i;
register C_VERTEX *cv;
FVECT v;
/* check argument count and type */
if (ac < 4)
return(MG_EARGC);
if ((mat = material()) == NULL) /* get material */
return(MG_EBADMAT);
if (ac <= 5) { /* check for smoothing */
C_VERTEX *cva[5];
for (i = 1; i < ac; i++) {
if ((cva[i-1] = c_getvert(av[i])) == NULL)
return(MG_EUNDEF);
if (is0vect(cva[i-1]->n))
break;
}
if (i < ac)
i = ISFLAT;
else
i = flat_tri(cva[0]->p, cva[1]->p, cva[2]->p,
cva[0]->n, cva[1]->n, cva[2]->n);
if (i == DEGEN)
return(MG_OK); /* degenerate (error?) */
if (i == RVBENT) {
myi = !myi;
i = ISBENT;
} else if (i == RVFLAT) {
myi = !myi;
i = ISFLAT;
}
if (i == ISBENT) { /* smoothed triangles */
do_tri(mat, cva[0], cva[1], cva[2], myi);
if (ac == 5)
do_tri(mat, cva[2], cva[3], cva[0], myi);
return(MG_OK);
}
}
/* spit out unsmoothed primitive */
printf("\n%s polygon %sf%d\n", mat, object(), ++nfaces);
printf("0\n0\n%d\n", 3*(ac-1));
for (i = 1; i < ac; i++) { /* get, transform, print each vertex */
if ((cv = c_getvert(av[myi ? ac-i : i])) == NULL)
return(MG_EUNDEF);
xf_xfmpoint(v, cv->p);
putv(v);
}
return(MG_OK);
}
void
triangle( /* put out a triangle */
char *pn,
char *mod,
char *obj,
VERTEX *v1,
VERTEX *v2,
VERTEX *v3
)
{
static char vfmt[] = "%18.12g %18.12g %18.12g\n";
static int ntri = 0;
int flatness = ISFLAT;
BARYCCM bvecs;
RREAL bvm[3][3];
int i;
/* compute barycentric coordinates */
if (v1->flags & v2->flags & v3->flags & (V_HASINDX|V_HASNORM))
if (comp_baryc(&bvecs, v1->pos, v2->pos, v3->pos) < 0)
return;
/* check flatness */
if (v1->flags & v2->flags & v3->flags & V_HASNORM) {
flatness = flat_tri(v1->pos, v2->pos, v3->pos,
v1->nor, v2->nor, v3->nor);
if (flatness == DEGEN)
return;
}
/* put out texture (if any) */
if (flatness == ISBENT || flatness == RVBENT) {
printf("\n%s texfunc %s\n", mod, TEXNAME);
mod = TEXNAME;
printf("4 dx dy dz %s\n", TCALNAME);
printf("0\n");
for (i = 0; i < 3; i++) {
bvm[i][0] = v1->nor[i];
bvm[i][1] = v2->nor[i];
bvm[i][2] = v3->nor[i];
}
put_baryc(&bvecs, bvm, 3);
}
/* put out pattern (if any) */
if (*pn && (v1->flags & v2->flags & v3->flags & V_HASINDX)) {
printf("\n%s colorpict %s\n", mod, PATNAME);
mod = PATNAME;
printf("7 noneg noneg noneg %s %s u v\n", pn, TCALNAME);
printf("0\n");
for (i = 0; i < 2; i++) {
bvm[i][0] = v1->ndx[i];
bvm[i][1] = v2->ndx[i];
bvm[i][2] = v3->ndx[i];
}
put_baryc(&bvecs, bvm, 2);
}
/* put out (reversed) triangle */
printf("\n%s polygon %s.%d\n", mod, obj, ++ntri);
printf("0\n0\n9\n");
if (flatness == RVFLAT || flatness == RVBENT) {
printf(vfmt, v3->pos[0],v3->pos[1],v3->pos[2]);
printf(vfmt, v2->pos[0],v2->pos[1],v2->pos[2]);
printf(vfmt, v1->pos[0],v1->pos[1],v1->pos[2]);
} else {
printf(vfmt, v1->pos[0],v1->pos[1],v1->pos[2]);
printf(vfmt, v2->pos[0],v2->pos[1],v2->pos[2]);
printf(vfmt, v3->pos[0],v3->pos[1],v3->pos[2]);
}
}
int /* create an extended triangle */
cvtri(
OBJECT mo,
FVECT vp1,
FVECT vp2,
FVECT vp3,
FVECT vn1,
FVECT vn2,
FVECT vn3,
RREAL vc1[2],
RREAL vc2[2],
RREAL vc3[2]
)
{
static OBJECT fobj = OVOID;
char buf[32];
int flags;
TRIDATA *ts;
FACE *f;
OBJREC *fop;
int j;
flags = MT_V; /* check what we have */
if (vn1 != NULL && vn2 != NULL && vn3 != NULL) {
RREAL *rp;
switch (flat_tri(vp1, vp2, vp3, vn1, vn2, vn3)) {
case ISBENT:
flags |= MT_N;
/* fall through */
case ISFLAT:
break;
case RVBENT:
flags |= MT_N;
rp = vn1; vn1 = vn3; vn3 = rp;
/* fall through */
case RVFLAT:
rp = vp1; vp1 = vp3; vp3 = rp;
rp = vc1; vc1 = vc3; vc3 = rp;
break;
case DEGEN:
error(WARNING, "degenerate triangle");
return(0);
default:
error(INTERNAL, "bad return from flat_tri()");
}
}
if (vc1 != NULL && vc2 != NULL && vc3 != NULL)
flags |= MT_UV;
if (fobj == OVOID) { /* create new triangle object */
fobj = newobject();
if (fobj == OVOID)
goto nomem;
fop = objptr(fobj);
fop->omod = mo;
fop->otype = OBJ_FACE;
sprintf(buf, "t%ld", (long)fobj);
fop->oname = savqstr(buf);
fop->oargs.nfargs = 9;
fop->oargs.farg = (RREAL *)malloc(9*sizeof(RREAL));
if (fop->oargs.farg == NULL)
goto nomem;
} else { /* else reuse failed one */
fop = objptr(fobj);
if (fop->otype != OBJ_FACE || fop->oargs.nfargs != 9)
error(CONSISTENCY, "code error 1 in cvtri");
}
for (j = 3; j--; ) {
fop->oargs.farg[j] = vp1[j];
fop->oargs.farg[3+j] = vp2[j];
fop->oargs.farg[6+j] = vp3[j];
}
/* create face record */
f = getface(fop);
if (f->area == 0.) {
free_os(fop);
return(0);
}
if (fop->os != (char *)f)
error(CONSISTENCY, "code error 2 in cvtri");
/* follow with auxliary data */
f = (FACE *)realloc((void *)f, sizeof(FACE)+tdsize(flags));
if (f == NULL)
goto nomem;
fop->os = (char *)f;
ts = (TRIDATA *)(f+1);
ts->fl = flags;
ts->obj = OVOID;
if (flags & MT_N)
for (j = 3; j--; ) {
ts->vn[0][j] = vn1[j];
ts->vn[1][j] = vn2[j];
ts->vn[2][j] = vn3[j];
}
if (flags & MT_UV)
for (j = 2; j--; ) {
ts->vc[0][j] = vc1[j];
ts->vc[1][j] = vc2[j];
ts->vc[2][j] = vc3[j];
}
else
vc1 = vc2 = vc3 = NULL;
/* update bounds */
add2bounds(vp1, vc1);
add2bounds(vp2, vc2);
add2bounds(vp3, vc3);
fobj = OVOID; /* we used this one */
return(1);
nomem:
error(SYSTEM, "out of memory in cvtri");
return(0);
}
int
puttri( /* put out a triangle */
char *v1,
char *v2,
char *v3
)
{
char *mod;
VNDX v1i, v2i, v3i;
BARYCCM bvecs;
RREAL bcoor[3][3];
int texOK = 0, patOK;
int flatness;
int i;
if ((mod = getmtl()) == NULL)
return(-1);
if (!cvtndx(v1i, v1) || !cvtndx(v2i, v2) || !cvtndx(v3i, v3))
return(0);
/* compute barycentric coordinates */
if (v1i[2]>=0 && v2i[2]>=0 && v3i[2]>=0)
flatness = flat_tri(vlist[v1i[0]], vlist[v2i[0]], vlist[v3i[0]],
vnlist[v1i[2]], vnlist[v2i[2]], vnlist[v3i[2]]);
else
flatness = ISFLAT;
switch (flatness) {
case DEGEN: /* zero area */
ndegen++;
return(-1);
case RVFLAT: /* reversed normals, but flat */
case ISFLAT: /* smoothing unnecessary */
texOK = 0;
break;
case RVBENT: /* reversed normals with smoothing */
case ISBENT: /* proper smoothing */
texOK = 1;
break;
}
if (flatten)
texOK = 0;
#ifdef TEXMAPS
patOK = mapname[0] && (v1i[1]>=0 && v2i[1]>=0 && v3i[1]>=0);
#else
patOK = 0;
#endif
if (texOK | patOK)
if (comp_baryc(&bvecs, vlist[v1i[0]], vlist[v2i[0]],
vlist[v3i[0]]) < 0)
texOK = patOK = 0;
/* put out texture (if any) */
if (texOK) {
printf("\n%s texfunc %s\n", mod, TEXNAME);
mod = TEXNAME;
printf("4 dx dy dz %s\n", TCALNAME);
printf("0\n");
for (i = 0; i < 3; i++) {
bcoor[i][0] = vnlist[v1i[2]][i];
bcoor[i][1] = vnlist[v2i[2]][i];
bcoor[i][2] = vnlist[v3i[2]][i];
}
put_baryc(&bvecs, bcoor, 3);
}
#ifdef TEXMAPS
/* put out pattern (if any) */
if (patOK) {
printf("\n%s colorpict %s\n", mod, PATNAME);
mod = PATNAME;
printf("7 noneg noneg noneg %s %s u v\n", mapname, TCALNAME);
printf("0\n");
for (i = 0; i < 2; i++) {
bcoor[i][0] = vtlist[v1i[1]][i];
bcoor[i][1] = vtlist[v2i[1]][i];
bcoor[i][2] = vtlist[v3i[1]][i];
}
put_baryc(&bvecs, bcoor, 2);
}
#endif
/* put out (reversed) triangle */
printf("\n%s polygon %s.%d\n", mod, getonm(), faceno);
printf("0\n0\n9\n");
if (flatness == RVFLAT || flatness == RVBENT) {
pvect(vlist[v3i[0]]);
pvect(vlist[v2i[0]]);
pvect(vlist[v1i[0]]);
} else {
pvect(vlist[v1i[0]]);
pvect(vlist[v2i[0]]);
pvect(vlist[v3i[0]]);
}
return(1);
}
