src/common/objutil.c

#ifndef lint
static const char RCSid[] = "$Id: objutil.c,v 2.13 2021/03/03 18:53:08 greg Exp $";
#endif
/*
 *  Basic .OBJ scene handling routines.
 *
 *  Created by Greg Ward on Wed Feb 11 2004.
 */

#include <stdlib.h>
#include <ctype.h>
#include "rtio.h"
#include "rtmath.h"
#include "rterror.h"
#include "lookup.h"
#include "objutil.h"

/* Find an existing name in a list of names */
int
findName(const char *nm, const char **nmlist, int n)
{
        int     i;
        
        for (i = n; i-- > 0; )
                if (!strcmp(nmlist[i], nm))
                        break;
        return(i);
}

/* Clear face selection */
void
clearSelection(Scene *sc, int set)
{
        Face    *f;
        
        for (f = sc->flist; f != NULL; f = f->next)
                if (set)
                        f->flags |= FACE_SELECTED;
                else
                        f->flags &= ~FACE_SELECTED;
}

/* Select faces by object name (modifies current) */
void
selectGroup(Scene *sc, const char *gname, int invert)
{
        int     gid = getGroupID(sc, gname);
        Face    *f;

        if (gid < 0)
                return;
        for (f = sc->flist; f != NULL; f = f->next)
                if (f->grp == gid) {
                        if (invert)
                                f->flags &= ~FACE_SELECTED;
                        else
                                f->flags |= FACE_SELECTED;
                }
}

/* Select faces by material name (modifies current) */
void
selectMaterial(Scene *sc, const char *mname, int invert)
{
        int     mid = getMaterialID(sc, mname);
        Face    *f;
        
        if (mid < 0)
                return;
        for (f = sc->flist; f != NULL; f = f->next)
                if (f->mat == mid) {
                        if (invert)
                                f->flags &= ~FACE_SELECTED;
                        else
                                f->flags |= FACE_SELECTED;
                }
}

/* Invert face selection */
void
invertSelection(Scene *sc)
{
        Face    *f;
        
        for (f = sc->flist; f != NULL; f = f->next)
                f->flags ^= FACE_SELECTED;
}

/* Count selected faces */
int
numberSelected(Scene *sc)
{
        int     nsel = 0;
        Face    *f;
        
        for (f = sc->flist; f != NULL; f = f->next)
                nsel += ((f->flags & FACE_SELECTED) != 0);
        return(nsel);
}

/* Execute callback on indicated faces */
int
foreachFace(Scene *sc, int (*cb)(Scene *, Face *, void *),
                        int flreq, int flexc, void *c_data)
{
        const int       fltest = flreq | flexc;
        int             sum = 0;
        Face            *f;
        
        if ((sc == NULL) | (cb == NULL))
                return(0);
        for (f = sc->flist; f != NULL; f = f->next)
                if ((f->flags & fltest) == flreq) {
                        int     res = (*cb)(sc, f, c_data);
                        if (res < 0)
                                return(res);
                        sum += res;
                }
        return(sum);
}

/* Callback for removeTexture() */
static int
remFaceTexture(Scene *sc, Face *f, void *dummy)
{
        int     hadTexture = 0;
        int     i;
        
        for (i = f->nv; i-- > 0; ) {
                if (f->v[i].tid < 0)
                        continue;
                f->v[i].tid = -1;
                hadTexture = 1;
        }
        return(hadTexture);
}

/* Remove texture coordinates from the indicated faces */
int
removeTexture(Scene *sc, int flreq, int flexc)
{
        return(foreachFace(sc, remFaceTexture, flreq, flexc, NULL));
}

/* Callback for removeNormals() */
static int
remFaceNormal(Scene *sc, Face *f, void *dummy)
{
        int     hadNormal = 0;
        int     i;
        
        for (i = f->nv; i-- > 0; ) {
                if (f->v[i].nid < 0)
                        continue;
                f->v[i].nid = -1;
                hadNormal = 1;
        }
        return(hadNormal);
}

/* Remove surface normals from the indicated faces */
int
removeNormals(Scene *sc, int flreq, int flexc)
{
        return(foreachFace(sc, remFaceNormal, flreq, flexc, NULL));
}

/* Callback for changeGroup() */
static int
chngFaceGroup(Scene *sc, Face *f, void *ptr)
{
        int     grp = *(int *)ptr;

        if (f->grp == grp)
                return(0);
        f->grp = grp;
        return(1);
}

/* Change group for the indicated faces */
int
changeGroup(Scene *sc, const char *gname, int flreq, int flexc)
{
        int     grp = getGroupID(sc, gname);

        if (grp < 0) {
                sc->grpname = chunk_alloc(char *, sc->grpname, sc->ngrps);
                sc->grpname[grp=sc->ngrps++] = savqstr((char *)gname);
        }
        return(foreachFace(sc, chngFaceGroup, flreq, flexc, (void *)&grp));
}

/* Callback for changeMaterial() */
static int
chngFaceMaterial(Scene *sc, Face *f, void *ptr)
{
        int     mat = *(int *)ptr;

        if (f->mat == mat)
                return(0);
        f->mat = mat;
        return(1);
}

/* Change material for the indicated faces */
int
changeMaterial(Scene *sc, const char *mname, int flreq, int flexc)
{
        int     mat = getMaterialID(sc, mname);

        if (mat < 0) {
                sc->matname = chunk_alloc(char *, sc->matname, sc->nmats);
                sc->matname[mat=sc->nmats++] = savqstr((char *)mname);
        }
        return(foreachFace(sc, chngFaceMaterial, flreq, flexc, (void *)&mat));
}

/* Compare floating point values for (near) equality */
static int
fdiffer(double f1, double f2, double eps)
{
        if (f2 != .0)
                f1 = f1/f2 - 1.;
        return((f1 > eps) | (f1 < -eps));
}

/* Compare two texture coordinates for (near) equality */
static int
tex_diff(const TexCoord *t1, const TexCoord *t2, double eps)
{
        if (fdiffer(t1->u, t2->u, eps))
                return(1);
        if (fdiffer(t1->v, t2->v, eps))
                return(1);
        return(0);
}

/* Compare two surface normals for (near) equality */
static int
norm_diff(const Normal n1, const Normal n2, double eps)
{
        if (fabs(n1[0]-n2[0]) > eps)
                return(1);
        if (fabs(n1[1]-n2[1]) > eps)
                return(1);
        if (fabs(n1[2]-n2[2]) > eps)
                return(1);
        return(0);
}

/* Replace the given vertex with an equivalent one */
static int
replace_vertex(Scene *sc, int prev, int repl, double eps)
{
        int     repl_tex[10];
        int     repl_norm[10];
        Face    *f, *flast=NULL;
        int     i, j=0;
                                        /* check to see if it's even used */
        if (sc->vert[prev].vflist == NULL)
                return(0);
                                        /* get replacement textures */
        repl_tex[0] = -1;
        for (f = sc->vert[repl].vflist; f != NULL; f = f->v[j].fnext) {
                                        /* make sure prev isn't in there */
                for (j = f->nv; j-- > 0; )
                        if (f->v[j].vid == prev)
                                return(0);
                for (j = f->nv; j-- > 0; )
                        if (f->v[j].vid == repl)
                                break;
                if (j < 0)
                        goto linkerr;
                if (f->v[j].tid < 0)
                        continue;
                                        /* see if it's new */
                for (i = 0; repl_tex[i] >= 0; i++) {
                        if (repl_tex[i] == f->v[j].tid)
                                break;
                        if (!tex_diff(&sc->tex[repl_tex[i]],
                                        &sc->tex[f->v[j].tid], eps)) {
                                f->v[j].tid = repl_tex[i];
                                break;  /* consolidate */
                        }
                }
                if (repl_tex[i] >= 0)
                        continue;       /* have this one already */
                                        /* else add it */
                repl_tex[i++] = f->v[j].tid;
                repl_tex[i] = -1;
                if (i >= 9)
                        break;          /* that's all we have room for */
        }
                                        /* get replacement normals */
        repl_norm[0] = -1;
        for (f = sc->vert[repl].vflist; f != NULL; f = f->v[j].fnext) {
                for (j = f->nv; j-- > 0; )
                        if (f->v[j].vid == repl)
                                break;
                if (f->v[j].nid < 0)
                        continue;
                                        /* see if it's new */
                for (i = 0; repl_norm[i] >= 0; i++) {
                        if (repl_norm[i] == f->v[j].nid)
                                break;
                        if (!norm_diff(sc->norm[repl_norm[i]],
                                        sc->norm[f->v[j].nid], eps)) {
                                f->v[j].nid = repl_norm[i];
                                break;  /* consolidate */
                        }
                }
                if (repl_norm[i] >= 0)
                        continue;       /* have this one already */
                                        /* else add it */
                repl_norm[i++] = f->v[j].nid;
                repl_norm[i] = -1;
                if (i >= 9)
                        break;          /* that's all we have room for */
        }
                                        /* replace occurrences of vertex */
        for (f = sc->vert[prev].vflist; f != NULL; f = f->v[j].fnext) {
                for (j = f->nv; j-- > 0; )
                        if (f->v[j].vid == prev)
                                break;
                if (j < 0)
                        goto linkerr;
                /* XXX doesn't allow for multiple references to prev in face */
                f->v[j].vid = repl;     /* replace vertex itself */
                if (faceArea(sc, f, NULL) <= FTINY*FTINY)
                        f->flags |= FACE_DEGENERATE;
                if (f->v[j].tid >= 0)   /* replace texture if appropriate */
                        for (i = 0; repl_tex[i] >= 0; i++) {
                                if (repl_tex[i] == f->v[j].tid)
                                        break;
                                if (!tex_diff(&sc->tex[repl_tex[i]],
                                                &sc->tex[f->v[j].tid], eps)) {
                                        f->v[j].tid = repl_tex[i];
                                        break;
                                }
                        }
                if (f->v[j].nid >= 0)   /* replace normal if appropriate */
                        for (i = 0; repl_norm[i] >= 0; i++) {
                                if (repl_norm[i] == f->v[j].nid)
                                        break;
                                if (!norm_diff(sc->norm[repl_norm[i]],
                                                sc->norm[f->v[j].nid], eps)) {
                                        f->v[j].nid = repl_norm[i];
                                        break;
                                }
                        }
                flast = f;
        }
                                        /* transfer face list */
        flast->v[j].fnext = sc->vert[repl].vflist;
        sc->vert[repl].vflist = sc->vert[prev].vflist;
        sc->vert[prev].vflist = NULL;
        return(1);
linkerr:
        error(CONSISTENCY, "Link error in replace_vertex()");
        return(0);                      /* shouldn't return */
}

/* Eliminate duplicate vertices, return # joined */
int
coalesceVertices(Scene *sc, double eps)
{
        int     nelim = 0;
        LUTAB   myLookup;
        LUENT   *le;
        char    vertfmt[32], vertbuf[64];
        double  d;
        int     i;
        
        if (eps >= 1.)
                return(0);
        if (sc->nverts <= 3)
                return(0);
                                        /* create hash table */
        myLookup.hashf = lu_shash;
        myLookup.keycmp = (lut_keycmpf_t *)strcmp;
        myLookup.freek = (lut_free_t *)freeqstr;
        myLookup.freed = NULL;
        if (!lu_init(&myLookup, sc->nverts))
                return(0);
        if (eps <= 5e-15)
                strcpy(vertfmt, "%.15e %.15e %.15e");
        else {
                int     nsigdig = 0;
                for (d = eps; d < 0.5; d *= 10.)
                        ++nsigdig;
                sprintf(vertfmt, "%%.%de %%.%de %%.%de",
                                nsigdig, nsigdig, nsigdig);
        }
                                        /* find coicident vertices */
        for (i = 0; i < sc->nverts; i++) {
                if (verbose && !((i+1) & 0x3fff))
                        fprintf(stderr, "%3d%% complete\r", 100*i/sc->nverts);
                                        /* check for match */
                sprintf(vertbuf, vertfmt, sc->vert[i].p[0],
                                sc->vert[i].p[1], sc->vert[i].p[2]);
                le = lu_find(&myLookup, vertbuf);
                if (le->data != NULL) { /* coincident vertex */
                        nelim += replace_vertex(sc, i,
                                        (Vertex *)le->data - sc->vert, eps);
                        continue;
                }
                if (le->key == NULL)    /* else create new entry */
                        le->key = savqstr(vertbuf);
                le->data = (char *)&sc->vert[i];
        }
        lu_done(&myLookup);             /* clean up */
        return(nelim);
}

/* Identify duplicate faces */
int
findDuplicateFaces(Scene *sc)
{
        int     nchecked = 0;
        int     nfound = 0;
        Face    *f, *f1;
        int     vid;
        int     i, j;
                                                /* start fresh */
        for (f = sc->flist; f != NULL; f = f->next)
                f->flags &= ~FACE_DUPLICATE;
                                                /* check each face */
        for (f = sc->flist; f != NULL; f = f->next) {
                nchecked++;
                if (verbose && !(nchecked & 0x3fff))
                        fprintf(stderr, "%3d%% complete\r",
                                        100*nchecked/sc->nfaces);
                if (f->flags & FACE_DUPLICATE)
                        continue;               /* already identified */
                vid = f->v[0].vid;
                                                /* look for duplicates */
                for (f1 = sc->vert[vid].vflist; f1 != NULL;
                                        f1 = f1->v[j].fnext) {
                        for (j = f1->nv; j-- > 0; )
                                if (f1->v[j].vid == vid)
                                        break;
                        if (j < 0)
                                break;          /* missing link! */
                        if (f1 == f)
                                continue;       /* shouldn't happen */
                        if (f1->flags & FACE_DUPLICATE)
                                continue;       /* already marked */
                        if (f1->nv != f->nv)
                                continue;       /* couldn't be dup. */
                        for (i = f->nv; --i > 0; )
                                if (f->v[i].vid != f1->v[(j+i)%f1->nv].vid)
                                        break;  /* vertex mismatch */
                        if (i) {
#if DUP_CHECK_REVERSE                           /* check reverse direction */
                                for (i = f->nv; --i > 0; )
                                        if (f1->v[(j+f1->nv-i)%f1->nv].vid
                                                        != f->v[i].vid)
                                                break;
                                if (i)          /* no match */
#endif
                                        continue;
                        }
                        f1->flags |= FACE_DUPLICATE;
                        ++nfound;
                }
        }
        if (verbose)
                fprintf(stderr, "Found %d duplicate faces\n", nfound);
        return(nfound);
}

/* Delete indicated faces */
int
deleteFaces(Scene *sc, int flreq, int flexc)
{
        const int       fltest = flreq | flexc;
        int             orig_nfaces = sc->nfaces;
        Face            fhead;
        Face            *f, *ftst;
        
        fhead.next = sc->flist;
        f = &fhead;
        while ((ftst = f->next) != NULL)
                if ((ftst->flags & fltest) == flreq) {
                        Face    *vf;            /* remove from vertex lists */
                        int     vid, i, j;
                        for (i = 0; i < ftst->nv; i++) {
                                vid = ftst->v[i].vid;
                                vf = sc->vert[vid].vflist;
                                if (vf == ftst) {
                                        sc->vert[vid].vflist = ftst->v[i].fnext;
                                        continue;
                                }
                                while (vf != NULL) {
                                        for (j = vf->nv; j-- > 0; )
                                                if (vf->v[j].vid == vid)
                                                        break;
                                        if (j < 0)
                                                break;  /* error */
                                        if (vf->v[j].fnext == ftst) {
                                                vf->v[j].fnext =
                                                        ftst->v[i].fnext;
                                                break;
                                        }
                                        vf = vf->v[j].fnext;
                                }
                        }
                        f->next = ftst->next;   /* remove from scene list */
                        efree((char *)ftst);
                        sc->nfaces--;
                } else
                        f = f->next;
        sc->flist = fhead.next;
        return(orig_nfaces - sc->nfaces);
}

/* Compute face area (and normal) */
double
faceArea(const Scene *sc, const Face *f, Normal nrm)
{
        FVECT   fnrm;
        double  area;
        FVECT   v1, v2, v3;
        double  *p0;
        int     i;
        
        if (f->flags & FACE_DEGENERATE)
                return(.0);                     /* should we check this? */
        fnrm[0] = fnrm[1] = fnrm[2] = .0;
        p0 = sc->vert[f->v[0].vid].p;
        VSUB(v1, sc->vert[f->v[1].vid].p, p0);
        for (i = 2; i < f->nv; i++) {
                VSUB(v2, sc->vert[f->v[i].vid].p, p0);
                fcross(v3, v1, v2);
                VADD(fnrm, fnrm, v3);
                VCOPY(v1, v2);
        }
        area = 0.5*normalize(fnrm);
        if (nrm != NULL) {
                if (area != 0.)
                        VCOPY(nrm, fnrm);
                else
                        nrm[0] = nrm[1] = nrm[2] = 0.;
        }
        return(area);
}

/* Add a descriptive comment */
void
addComment(Scene *sc, const char *comment)
{
        sc->descr = chunk_alloc(char *, sc->descr, sc->ndescr);
        sc->descr[sc->ndescr++] = savqstr((char *)comment);
}

/* Find index for comment containing the given string (starting from n) */
int
findComment(Scene *sc, const char *match, int n)
{
        if (n >= sc->ndescr)
                return(-1);
        n *= (n > 0);
        while (n < sc->ndescr)
                if (strstr(sc->descr[n], match) != NULL)
                        return(n);
        return(-1);
}

/* Clear comments */
void
clearComments(Scene *sc)
{
        while (sc->ndescr > 0)
                freeqstr(sc->descr[--sc->ndescr]);
        efree((char *)sc->descr);
        sc->ndescr = 0;
}

/* Add a face to a vertex face list */
static void
add2facelist(Scene *sc, Face *f, int i)
{
        int     vid = f->v[i].vid;
        Face    *fp = sc->vert[vid].vflist;
        int     j;
        
        f->v[i].fnext = NULL;                   /* will put at end */
        if (fp == NULL) {                       /* new list */
                sc->vert[vid].vflist = f;
                return;
        }
        for ( ; ; ) {                           /* else find position */
                if (fp == f)
                        return;                 /* already in list */
                for (j = fp->nv; j-- > 0; )
                        if (fp->v[j].vid == vid)
                                break;
                if (j < 0)
                        error(CONSISTENCY, "Link error in add2facelist()");
                if (fp->v[j].fnext == NULL)
                        break;                  /* reached the end */
                fp = fp->v[j].fnext;
        }
        fp->v[j].fnext = f;                     /* append new face */
}

/* Allocate an empty scene */
Scene *
newScene(void)
{
        Scene   *sc = (Scene *)ecalloc(1, sizeof(Scene));
                                                /* default group & material */
        sc->grpname = chunk_alloc(char *, sc->grpname, sc->ngrps);
        sc->grpname[sc->ngrps++] = savqstr("DEFAULT_GROUP");
        sc->matname = chunk_alloc(char *, sc->matname, sc->nmats);
        sc->matname[sc->nmats++] = savqstr("DEFAULT_MATERIAL");

        return(sc);
}

/* Add a vertex to a scene */
int
addVertex(Scene *sc, double x, double y, double z)
{
        sc->vert = chunk_alloc(Vertex, sc->vert, sc->nverts);
        sc->vert[sc->nverts].p[0] = x;
        sc->vert[sc->nverts].p[1] = y;
        sc->vert[sc->nverts].p[2] = z;
        sc->vert[sc->nverts].vflist = NULL;
        return(sc->nverts++);
}

/* Add a texture coordinate to a scene */
int
addTexture(Scene *sc, double u, double v)
{
        sc->tex = chunk_alloc(TexCoord, sc->tex, sc->ntex);
        sc->tex[sc->ntex].u = u;
        sc->tex[sc->ntex].v = v;
        return(sc->ntex++);
}

/* Add a surface normal to a scene */
int
addNormal(Scene *sc, double xn, double yn, double zn)
{
        FVECT   nrm;

        nrm[0] = xn; nrm[1] = yn; nrm[2] = zn;
        if (normalize(nrm) == .0)
                return(-1);
        sc->norm = chunk_alloc(Normal, sc->norm, sc->nnorms);
        VCOPY(sc->norm[sc->nnorms], nrm);
        return(sc->nnorms++);
}

/* Set current (last) group */
void
setGroup(Scene *sc, const char *nm)
{
        sc->lastgrp = getGroupID(sc, nm);
        if (sc->lastgrp >= 0)
                return;
        sc->grpname = chunk_alloc(char *, sc->grpname, sc->ngrps);
        sc->grpname[sc->lastgrp=sc->ngrps++] = savqstr((char *)nm);
}

/* Set current (last) material */
void
setMaterial(Scene *sc, const char *nm)
{
        sc->lastmat = getMaterialID(sc, nm);
        if (sc->lastmat >= 0)
                return;
        sc->matname = chunk_alloc(char *, sc->matname, sc->nmats);
        sc->matname[sc->lastmat=sc->nmats++] = savqstr((char *)nm);
}

/* Add new face to a scene */
Face *
addFace(Scene *sc, VNDX vid[], int nv)
{
        Face    *f;
        int     i;
        
        if (nv < 3)
                return(NULL);
        f = (Face *)emalloc(sizeof(Face)+sizeof(VertEnt)*(nv-3));
        f->flags = 0;
        f->nv = nv;
        f->grp = sc->lastgrp;
        f->mat = sc->lastmat;
        for (i = 0; i < nv; i++) {              /* add each vertex */
                int     j;
                f->v[i].vid = vid[i][0];
                f->v[i].tid = vid[i][1];
                f->v[i].nid = vid[i][2];
                f->v[i].fnext = NULL;
                for (j = i; j-- > 0; )
                        if (f->v[j].vid == vid[i][0])
                                break;
                if (j < 0) {                    /* first occurrence? */
                        f->v[i].fnext = sc->vert[vid[i][0]].vflist;
                        sc->vert[vid[i][0]].vflist = f;
                } else if (nv == 3)             /* degenerate triangle? */
                        f->flags |= FACE_DEGENERATE;
        }
        f->next = sc->flist;                    /* push onto face list */
        sc->flist = f;
        sc->nfaces++;
                                                /* check face area */
        if (!(f->flags & FACE_DEGENERATE) && faceArea(sc, f, NULL) <= FTINY*FTINY)
                f->flags |= FACE_DEGENERATE;
        return(f);
}

/* Duplicate a scene, optionally selecting faces */
Scene *
dupScene(const Scene *osc, int flreq, int flexc)
{
        int             fltest = flreq | flexc;
        Scene           *sc;
        const Face      *fo;
        Face            *f;
        int             i;

        if (osc == NULL)
                return(NULL);
        sc = newScene();
        for (i = 0; i < osc->ndescr; i++)
                addComment(sc, osc->descr[i]);
        if (osc->ngrps) {
                sc->grpname = (char **)emalloc(sizeof(char *) *
                                                (osc->ngrps+(CHUNKSIZ-1)));
                for (i = 0; i < osc->ngrps; i++)
                        sc->grpname[i] = savqstr(osc->grpname[i]);
                sc->ngrps = osc->ngrps;
        }
        if (osc->nmats) {
                sc->matname = (char **)emalloc(sizeof(char *) *
                                                (osc->nmats+(CHUNKSIZ-1)));
                for (i = 0; i < osc->nmats; i++)
                        sc->matname[i] = savqstr(osc->matname[i]);
                sc->nmats = osc->nmats;
        }
        if (osc->nverts) {
                sc->vert = (Vertex *)emalloc(sizeof(Vertex) *
                                                (osc->nverts+(CHUNKSIZ-1)));
                memcpy((void *)sc->vert, (const void *)osc->vert,
                                sizeof(Vertex)*osc->nverts);
                sc->nverts = osc->nverts;
                for (i = 0; i < sc->nverts; i++)
                        sc->vert[i].vflist = NULL;
        }
        if (osc->ntex) {
                sc->tex = (TexCoord *)emalloc(sizeof(TexCoord) *
                                                (osc->ntex+(CHUNKSIZ-1)));
                memcpy((void *)sc->tex, (const void *)osc->tex,
                                sizeof(TexCoord)*osc->ntex);
                sc->ntex = osc->ntex;
        }
        if (osc->nnorms) {
                sc->norm = (Normal *)emalloc(sizeof(Normal) *
                                                (osc->nnorms+CHUNKSIZ));
                memcpy((void *)sc->norm, (const void *)osc->norm,
                                sizeof(Normal)*osc->nnorms);
                sc->nnorms = osc->nnorms;
        }
        for (fo = osc->flist; fo != NULL; fo = fo->next) {
                if ((fo->flags & fltest) != flreq)
                        continue;
                f = (Face *)emalloc(sizeof(Face) +
                                sizeof(VertEnt)*(fo->nv-3));
                memcpy((void *)f, (const void *)fo, sizeof(Face) +
                                sizeof(VertEnt)*(fo->nv-3));
                for (i = 0; i < f->nv; i++)
                        add2facelist(sc, f, i);
                f->next = sc->flist;
                sc->flist = f;
                sc->nfaces++;
        }
        deleteUnreferenced(sc);         /* jetsam */
        return(sc);
}

/* Add one scene to another, not checking for redundancies */
int
addScene(Scene *scdst, const Scene *scsrc)
{
        VNDX            my_vlist[4];
        int             *vert_map = NULL;
        int             *norm_map = NULL;
        int             *tex_map = NULL;
        VNDX            *vlist = my_vlist;
        int             vllen = sizeof(my_vlist)/sizeof(VNDX);
        int             cur_mat = 0;
        int             cur_grp = 0;
        int             fcnt = 0;
        const Face      *f;
        int             i;

        if ((scdst == NULL) | (scsrc == NULL))
                return(-1);
        if (scsrc->nfaces <= 0)
                return(0);
                                        /* map vertices */
        vert_map = (int *)emalloc(sizeof(int *)*scsrc->nverts);
        for (i = 0; i < scsrc->nverts; i++) {
                const Vertex    *v = scsrc->vert + i;
                if (v->vflist == NULL) {
                        vert_map[i] = -1;
                        continue;
                }
                vert_map[i] = addVertex(scdst, v->p[0], v->p[1], v->p[2]);
        }
        if (scsrc->ntex > 0)            /* map texture coords */
                tex_map = (int *)emalloc(sizeof(int *)*scsrc->ntex);
        for (i = 0; i < scsrc->ntex; i++) {
                const TexCoord  *t = scsrc->tex + i;
                tex_map[i] = addTexture(scdst, t->u, t->v);
        }
        if (scsrc->nnorms > 0)          /* map normals */
                norm_map = (int *)emalloc(sizeof(int *)*scsrc->nnorms);
        for (i = 0; i < scsrc->nnorms; i++) {
                const float     *n = scsrc->norm[i];
                norm_map[i] = addNormal(scdst, n[0], n[1], n[2]);
        }
                                        /* add faces */
        scdst->lastgrp = scdst->lastmat = 0;
        for (f = scsrc->flist; f != NULL; f = f->next) {
                if (f->grp != cur_grp)
                        setGroup(scdst, scsrc->grpname[cur_grp = f->grp]);
                if (f->mat != cur_mat)
                        setMaterial(scdst, scsrc->matname[cur_mat = f->mat]);
                if (f->nv > vllen) {
                        if (vlist == my_vlist)
                                vlist = (VNDX *)emalloc(
                                                sizeof(VNDX)*(vllen = f->nv));
                        else
                                vlist = (VNDX *)erealloc((char *)vlist,
                                                sizeof(VNDX)*(vllen = f->nv));
                }
                memset(vlist, 0xff, sizeof(VNDX)*f->nv);
                for (i = f->nv; i-- > 0; ) {
                        if (f->v[i].vid >= 0)
                                vlist[i][0] = vert_map[f->v[i].vid];
                        if (f->v[i].tid >= 0)
                                vlist[i][1] = tex_map[f->v[i].tid];
                        if (f->v[i].nid >= 0)
                                vlist[i][2] = norm_map[f->v[i].nid];
                }
                fcnt += (addFace(scdst, vlist, f->nv) != NULL);
        }
                                        /* clean up */
        if (vlist != my_vlist) efree((char *)vlist);
        if (norm_map != NULL) efree((char *)norm_map);
        if (tex_map != NULL) efree((char *)tex_map);
        efree((char *)vert_map);
        return(fcnt);
}

#define MAXAC   100

/* Transform entire scene */
int
xfScene(Scene *sc, int xac, char *xav[])
{
        char    comm[24+MAXAC*8];
        char    *cp;
        XF      myxf;
        FVECT   vec;
        int     i;

        if ((sc == NULL) | (xac <= 0) | (xav == NULL))
                return(0);
                                        /* compute matrix */
        if (xf(&myxf, xac, xav) < xac)
                return(0);
                                        /* transform vertices */
        for (i = 0; i < sc->nverts; i++) {
                VCOPY(vec, sc->vert[i].p);
                multp3(vec, vec, myxf.xfm);
                VCOPY(sc->vert[i].p, vec);
        }
                                        /* transform normals */
        for (i = 0; i < sc->nnorms; i++) {
                VCOPY(vec, sc->norm[i]);
                multv3(vec, vec, myxf.xfm);
                vec[0] /= myxf.sca; vec[1] /= myxf.sca; vec[2] /= myxf.sca;
                VCOPY(sc->norm[i], vec);
        }
                                        /* add comment */
        cp = strcpy(comm, "Transformed by:");
        for (i = 0; i < xac; i++) {
                while (*cp) cp++;
                *cp++ = ' ';
                strcpy(cp, xav[i]);
        }
        addComment(sc, comm);
        return(xac);                    /* all done */
}

/* Ditto, using transform string rather than pre-parsed words */
int
xfmScene(Scene *sc, const char *xfm)
{
        char    *xav[MAXAC+1];
        int     xac, i;

        if ((sc == NULL) | (xfm == NULL))
                return(0);
                                        /* skip spaces at beginning */
        while (isspace(*xfm))
                xfm++;
        if (!*xfm)
                return(0);
                                        /* parse string into words */
        xav[0] = strcpy((char *)emalloc(strlen(xfm)+1), xfm);
        xac = 1; i = 0;
        for ( ; ; ) {
                while (!isspace(xfm[++i]))
                        if (!xfm[i])
                                break;
                while (isspace(xfm[i]))
                        xav[0][i++] = '\0';
                if (!xfm[i])
                        break;
                if (xac >= MAXAC-1) {
                        free(xav[0]);
                        return(0);
                }
                xav[xac++] = xav[0] + i;
        }
        xav[xac] = NULL;
        i = xfScene(sc, xac, xav);
        efree((char *)xav[0]);
        return(i);
}
#undef MAXAC

/* Delete unreferenced vertices, normals, texture coords */
void
deleteUnreferenced(Scene *sc)
{
        int     *vmap;
        Face    *f;
        int     nused, i;
                                                /* allocate index map */
        if (!sc->nverts)
                return;
        i = sc->nverts;
        if (sc->ntex > i)
                i = sc->ntex;
        if (sc->nnorms > i)
                i = sc->nnorms;
        vmap = (int *)emalloc(sizeof(int)*i);
                                                /* remap positions */
        for (i = nused = 0; i < sc->nverts; i++) {
                if (sc->vert[i].vflist == NULL) {
                        vmap[i] = -1;
                        continue;
                }
                if (nused != i)
                        sc->vert[nused] = sc->vert[i];
                vmap[i] = nused++;
        }
        if (nused == sc->nverts)
                goto skip_pos;
        sc->vert = (Vertex *)erealloc((char *)sc->vert,
                                sizeof(Vertex)*(nused+(CHUNKSIZ-1)));
        sc->nverts = nused;
        for (f = sc->flist; f != NULL; f = f->next)
                for (i = f->nv; i--; )
                        if ((f->v[i].vid = vmap[f->v[i].vid]) < 0)
                                error(CONSISTENCY,
                                        "Link error in del_unref_verts()");
skip_pos:
                                                /* remap texture coord's */
        if (!sc->ntex)
                goto skip_tex;
        memset((void *)vmap, 0, sizeof(int)*sc->ntex);
        for (f = sc->flist; f != NULL; f = f->next)
                for (i = f->nv; i--; )
                        if (f->v[i].tid >= 0)
                                vmap[f->v[i].tid] = 1;
        for (i = nused = 0; i < sc->ntex; i++) {
                if (!vmap[i])
                        continue;
                if (nused != i)
                        sc->tex[nused] = sc->tex[i];
                vmap[i] = nused++;
        }
        if (nused == sc->ntex)
                goto skip_tex;
        sc->tex = (TexCoord *)erealloc((char *)sc->tex,
                                sizeof(TexCoord)*(nused+(CHUNKSIZ-1)));
        sc->ntex = nused;
        for (f = sc->flist; f != NULL; f = f->next)
                for (i = f->nv; i--; )
                        if (f->v[i].tid >= 0)
                                f->v[i].tid = vmap[f->v[i].tid];
skip_tex:
                                                /* remap normals */
        if (!sc->nnorms)
                goto skip_norms;
        memset((void *)vmap, 0, sizeof(int)*sc->nnorms);
        for (f = sc->flist; f != NULL; f = f->next)
                for (i = f->nv; i--; )
                        if (f->v[i].nid >= 0)
                                vmap[f->v[i].nid] = 1;
        for (i = nused = 0; i < sc->nnorms; i++) {
                if (!vmap[i])
                        continue;
                if (nused != i)
                        memcpy((void *)sc->norm[nused],
                                        (void *)sc->norm[i],
                                        sizeof(Normal));
                vmap[i] = nused++;
        }
        if (nused == sc->nnorms)
                goto skip_norms;
        sc->norm = (Normal *)erealloc((char *)sc->norm,
                                sizeof(Normal)*(nused+(CHUNKSIZ-1)));
        sc->nnorms = nused;
        for (f = sc->flist; f != NULL; f = f->next)
                for (i = f->nv; i--; )
                        if (f->v[i].nid >= 0)
                                f->v[i].nid = vmap[f->v[i].nid];
skip_norms:
                                                /* clean up */
        efree((char *)vmap);
}

/* Free a scene */
void
freeScene(Scene *sc)
{
        int     i;
        Face    *f;
        
        if (sc == NULL)
                return;
        clearComments(sc);
        for (i = sc->ngrps; i-- > 0; )
                freeqstr(sc->grpname[i]);
        efree((char *)sc->grpname);
        for (i = sc->nmats; i-- > 0; )
                freeqstr(sc->matname[i]);
        efree((char *)sc->matname);
        efree((char *)sc->vert);
        efree((char *)sc->tex);
        efree((char *)sc->norm);
        while ((f = sc->flist) != NULL) {
                sc->flist = f->next;
                efree((char *)f);
        }
        efree((char *)sc);
}
Revision:	2.14
Committed:	Wed Apr 7 03:02:00 2021 UTC (3 years, 1 month ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.13:	+126 -46 lines
Log Message:	feat: created addScene() function to add one scene to another