src/rt/rtrace.c

#ifndef lint
static const char       RCSid[] = "$Id: rtrace.c,v 2.102 2021/04/16 16:31:35 greg Exp $";
#endif
/*
 *  rtrace.c - program and variables for individual ray tracing.
 */

#include "copyright.h"

/*
 *  Input is in the form:
 *
 *      xorg    yorg    zorg    xdir    ydir    zdir
 *
 *  The direction need not be normalized.  Output is flexible.
 *  If the direction vector is (0,0,0), then the output is flushed.
 *  All values default to ascii representation of real
 *  numbers.  Binary representations can be selected
 *  with '-ff' for float or '-fd' for double.  By default,
 *  radiance is computed.  The '-i' or '-I' options indicate that
 *  irradiance values are desired.
 */

#include  <time.h>

#include  "platform.h"
#include  "ray.h"
#include  "ambient.h"
#include  "source.h"
#include  "otypes.h"
#include  "otspecial.h"
#include  "resolu.h"
#include  "random.h"

extern int  inform;                     /* input format */
extern int  outform;                    /* output format */
extern char  *outvals;                  /* output values */

extern int  imm_irrad;                  /* compute immediate irradiance? */
extern int  lim_dist;                   /* limit distance? */

extern char  *tralist[];                /* list of modifers to trace (or no) */
extern int  traincl;                    /* include == 1, exclude == 0 */

extern int  hresolu;                    /* horizontal resolution */
extern int  vresolu;                    /* vertical resolution */

int  castonly = 0;                      /* only doing ray-casting? */

#ifndef  MAXTSET
#define  MAXTSET        8191            /* maximum number in trace set */
#endif
OBJECT  traset[MAXTSET+1]={0};          /* trace include/exclude set */

static int  Tflag = 0;                  /* source tracing enabled? */

static RAY  thisray;                    /* for our convenience */

static FILE  *inpfp = NULL;             /* input stream pointer */

static FVECT    *inp_queue = NULL;      /* ray input queue if flushing */
static int      inp_qpos = 0;           /* next ray to return */
static int      inp_qend = 0;           /* number of rays in this work group */

typedef void putf_t(RREAL *v, int n);
static putf_t puta, putd, putf, putrgbe;

typedef void oputf_t(RAY *r);
static oputf_t  oputo, oputd, oputv, oputV, oputl, oputL, oputc, oputp,
                oputr, oputR, oputx, oputX, oputn, oputN, oputs,
                oputw, oputW, oputm, oputM, oputtilde;

extern void tranotify(OBJECT obj);
static int is_fifo(FILE *fp);
static void bogusray(void);
static void raycast(RAY *r);
static void rayirrad(RAY *r);
static void rtcompute(FVECT org, FVECT dir, double dmax);
static int printvals(RAY *r);
static int getvec(FVECT vec, int fmt, FILE *fp);
static int iszerovec(const FVECT vec);
static double nextray(FVECT org, FVECT dir);
static void tabin(RAY *r);
static void ourtrace(RAY *r);

static oputf_t *ray_out[32], *every_out[32];
static putf_t *putreal;


void
quit(                   /* quit program */
        int  code
)
{
        if (ray_pnprocs > 0)    /* close children if any */
                ray_pclose(0);          
        else if (ray_pnprocs < 0)
                _exit(code);    /* avoid flush() in child */
#ifndef  NON_POSIX
        else {
                headclean();    /* delete header file */
                pfclean();      /* clean up persist files */
        }
#endif
        exit(code);
}


char *
formstr(                                /* return format identifier */
        int  f
)
{
        switch (f) {
        case 'a': return("ascii");
        case 'f': return("float");
        case 'd': return("double");
        case 'c': return(COLRFMT);
        }
        return("unknown");
}


static void
trace_sources(void)                     /* trace rays to light sources, also */
{
        int     sn;

        for (sn = 0; sn < nsources; sn++)
                source[sn].sflags |= SFOLLOW;
}


void
rtrace(                         /* trace rays from file */
        char  *fname,
        int  nproc
)
{
        unsigned long  vcount = (hresolu > 1) ? (unsigned long)hresolu*vresolu
                                              : (unsigned long)vresolu;
        long  nextflush = (!vresolu | (hresolu <= 1)) * hresolu;
        int  something2flush = 0;
        FILE  *fp;
        double  d;
        FVECT  orig, direc;
                                        /* set up input */
        if (fname == NULL)
                inpfp = stdin;
        else if ((inpfp = fopen(fname, "r")) == NULL) {
                sprintf(errmsg, "cannot open input file \"%s\"", fname);
                error(SYSTEM, errmsg);
        }
#ifdef getc_unlocked
        flockfile(inpfp);               /* avoid lock/unlock overhead */
        flockfile(stdout);
#endif
        if (inform != 'a')
                SET_FILE_BINARY(inpfp);
                                        /* set up output */
        if (castonly || every_out[0] != NULL)
                nproc = 1;              /* don't bother multiprocessing */
        if (Tflag && every_out[0] != NULL)
                trace_sources();        /* asking to trace light sources */
        if ((nextflush > 0) & (nproc > nextflush)) {
                error(WARNING, "reducing number of processes to match flush interval");
                nproc = nextflush;
        }
        if (nproc > 1) {                /* start multiprocessing */
                ray_popen(nproc);
                ray_fifo_out = printvals;
        }
        if (hresolu > 0) {
                if (vresolu > 0)
                        fprtresolu(hresolu, vresolu, stdout);
                else
                        fflush(stdout);
        }
                                        /* process input rays */
        while ((d = nextray(orig, direc)) >= 0.0) {
                if (d == 0.0) {                         /* flush request? */
                        if (something2flush) {
                                if (ray_pnprocs > 1 && ray_fifo_flush() < 0)
                                        error(USER, "child(ren) died");
                                bogusray();
                                fflush(stdout);
                                nextflush = (!vresolu | (hresolu <= 1)) * hresolu;
                                something2flush = 0;
                        } else
                                bogusray();
                } else {                                /* compute and print */
                        rtcompute(orig, direc, lim_dist ? d : 0.0);
                        if (!--nextflush) {             /* flush if time */
                                if (ray_pnprocs > 1 && ray_fifo_flush() < 0)
                                        error(USER, "child(ren) died");
                                fflush(stdout);
                                nextflush = hresolu;
                        } else
                                something2flush = 1;
                }
                if (ferror(stdout))
                        error(SYSTEM, "write error");
                if (vcount && !--vcount)                /* check for end */
                        break;
        }
        if (ray_pnprocs > 1) {                          /* clean up children */
                if (ray_fifo_flush() < 0)
                        error(USER, "unable to complete processing");
                ray_pclose(0);
        }
        if (vcount)
                error(WARNING, "unexpected EOF on input");
        if (fflush(stdout) < 0)
                error(SYSTEM, "write error");
        if (fname != NULL) {
                fclose(inpfp);
                inpfp = NULL;
        }
        nextray(NULL, NULL);
}


int
setrtoutput(void)                       /* set up output tables, return #comp */
{
        char  *vs = outvals;
        oputf_t **table = ray_out;
        int  ncomp = 0;

        if (!*vs)
                error(USER, "empty output specification");

        switch (outform) {      /* make sure (*putreal)() calls someone! */
        case 'a': putreal = puta; break;
        case 'f': putreal = putf; break;
        case 'd': putreal = putd; break;
        case 'c':
                if (outvals[1] || !strchr("vrx", outvals[0]))
                        error(USER, "color format only with -ov, -or, -ox");
                putreal = putrgbe; break;
        default:
                error(CONSISTENCY, "botched output format");
        }
        castonly = 1;                   /* sets castonly as side-effect */
        do
                switch (*vs) {
                case 'T':                               /* trace sources */
                        Tflag++;
                        /* fall through */
                case 't':                               /* trace */
                        if (!vs[1]) break;
                        *table = NULL;
                        table = every_out;
                        trace = ourtrace;
                        castonly = 0;
                        break;
                case 'o':                               /* origin */
                        *table++ = oputo;
                        ncomp += 3;
                        break;
                case 'd':                               /* direction */
                        *table++ = oputd;
                        ncomp += 3;
                        break;
                case 'r':                               /* reflected contrib. */
                        *table++ = oputr;
                        ncomp += 3;
                        castonly = 0;
                        break;
                case 'R':                               /* reflected distance */
                        *table++ = oputR;
                        ncomp++;
                        castonly = 0;
                        break;
                case 'x':                               /* xmit contrib. */
                        *table++ = oputx;
                        ncomp += 3;
                        castonly = 0;
                        break;
                case 'X':                               /* xmit distance */
                        *table++ = oputX;
                        ncomp++;
                        castonly = 0;
                        break;
                case 'v':                               /* value */
                        *table++ = oputv;
                        ncomp += 3;
                        castonly = 0;
                        break;
                case 'V':                               /* contribution */
                        *table++ = oputV;
                        ncomp += 3;
                        castonly = 0;
                        if (ambounce > 0 && (ambacc > FTINY || ambssamp > 0))
                                error(WARNING,
                                        "-otV accuracy depends on -aa 0 -as 0");
                        break;
                case 'l':                               /* effective distance */
                        *table++ = oputl;
                        ncomp++;
                        castonly = 0;
                        break;
                case 'c':                               /* local coordinates */
                        *table++ = oputc;
                        ncomp += 2;
                        break;
                case 'L':                               /* single ray length */
                        *table++ = oputL;
                        ncomp++;
                        break;
                case 'p':                               /* point */
                        *table++ = oputp;
                        ncomp += 3;
                        break;
                case 'n':                               /* perturbed normal */
                        *table++ = oputn;
                        ncomp += 3;
                        castonly = 0;
                        break;
                case 'N':                               /* unperturbed normal */
                        *table++ = oputN;
                        ncomp += 3;
                        break;
                case 's':                               /* surface */
                        *table++ = oputs;
                        ncomp++;
                        break;
                case 'w':                               /* weight */
                        *table++ = oputw;
                        ncomp++;
                        break;
                case 'W':                               /* coefficient */
                        *table++ = oputW;
                        ncomp += 3;
                        castonly = 0;
                        if (ambounce > 0 && (ambacc > FTINY) | (ambssamp > 0))
                                error(WARNING,
                                        "-otW accuracy depends on -aa 0 -as 0");
                        break;
                case 'm':                               /* modifier */
                        *table++ = oputm;
                        ncomp++;
                        break;
                case 'M':                               /* material */
                        *table++ = oputM;
                        ncomp++;
                        break;
                case '~':                               /* tilde */
                        *table++ = oputtilde;
                        break;
                default:
                        sprintf(errmsg, "unrecognized output option '%c'", *vs);
                        error(USER, errmsg);
                }
        while (*++vs);

        *table = NULL;
        if (*every_out != NULL)
                ncomp = 0;
                                                        /* compatibility */
        if ((do_irrad | imm_irrad) && castonly)
                error(USER, "-I+ and -i+ options require some value output");
        for (table = ray_out; *table != NULL; table++) {
                if ((*table == oputV) | (*table == oputW))
                        error(WARNING, "-oVW options require trace mode");
                if ((do_irrad | imm_irrad) &&
                                (*table == oputr) | (*table == oputR) |
                                (*table == oputx) | (*table == oputX))
                        error(WARNING, "-orRxX options incompatible with -I+ and -i+");
        }
        return(ncomp);
}


static void
bogusray(void)                  /* print out empty record */
{
        rayorigin(&thisray, PRIMARY, NULL, NULL);
        printvals(&thisray);
}


static void
raycast(                        /* compute first ray intersection only */
        RAY *r
)
{
        if (!localhit(r, &thescene)) {
                if (r->ro == &Aftplane) {       /* clipped */
                        r->ro = NULL;
                        r->rot = FHUGE;
                } else
                        sourcehit(r);
        }
}


static void
rayirrad(                       /* compute irradiance rather than radiance */
        RAY *r
)
{
        void    (*old_revf)(RAY *) = r->revf;
                                        /* pretend we hit surface */
        r->rxt = r->rot = 1e-5;
        VSUM(r->rop, r->rorg, r->rdir, r->rot);
        r->ron[0] = -r->rdir[0];
        r->ron[1] = -r->rdir[1];
        r->ron[2] = -r->rdir[2];
        r->rod = 1.0;
                                        /* compute result */
        r->revf = raytrace;
        (*ofun[Lamb.otype].funp)(&Lamb, r);
        r->revf = old_revf;
}


static void
rtcompute(                      /* compute and print ray value(s) */
        FVECT  org,
        FVECT  dir,
        double  dmax
)
{
                                        /* set up ray */
        if (imm_irrad) {
                VSUM(thisray.rorg, org, dir, 1.1e-4);
                thisray.rdir[0] = -dir[0];
                thisray.rdir[1] = -dir[1];
                thisray.rdir[2] = -dir[2];
                thisray.rmax = 0.0;
        } else {
                VCOPY(thisray.rorg, org);
                VCOPY(thisray.rdir, dir);
                thisray.rmax = dmax;
        }
        rayorigin(&thisray, PRIMARY, NULL, NULL);
        if (imm_irrad)
                thisray.revf = rayirrad;
        else if (castonly)
                thisray.revf = raycast;
        if (ray_pnprocs > 1) {          /* multiprocessing FIFO? */
                if (ray_fifo_in(&thisray) < 0)
                        error(USER, "lost children");
                return;
        }
        samplendx++;                    /* else do it ourselves */
        rayvalue(&thisray);
        printvals(&thisray);
}


static int
printvals(                      /* print requested ray values */
        RAY  *r
)
{
        oputf_t **tp;

        if (ray_out[0] == NULL)
                return(0);
        for (tp = ray_out; *tp != NULL; tp++)
                (**tp)(r);
        if (outform == 'a')
                putchar('\n');
        return(1);
}


static int
is_fifo(                /* check if file pointer connected to pipe */
        FILE *fp
)
{
#ifdef S_ISFIFO
        struct stat  sbuf;

        if (fstat(fileno(fp), &sbuf) < 0)
                error(SYSTEM, "fstat() failed on input stream");
        return(S_ISFIFO(sbuf.st_mode));
#else
        return (fp == stdin);           /* just a guess, really */
#endif
}


static int
getvec(                 /* get a vector from fp */
        FVECT  vec,
        int  fmt,
        FILE  *fp
)
{
        static float  vf[3];
        static double  vd[3];
        char  buf[32];
        int  i;

        switch (fmt) {
        case 'a':                                       /* ascii */
                for (i = 0; i < 3; i++) {
                        if (fgetword(buf, sizeof(buf), fp) == NULL ||
                                        !isflt(buf))
                                return(-1);
                        vec[i] = atof(buf);
                }
                break;
        case 'f':                                       /* binary float */
                if (getbinary(vf, sizeof(float), 3, fp) != 3)
                        return(-1);
                VCOPY(vec, vf);
                break;
        case 'd':                                       /* binary double */
                if (getbinary(vd, sizeof(double), 3, fp) != 3)
                        return(-1);
                VCOPY(vec, vd);
                break;
        default:
                error(CONSISTENCY, "botched input format");
        }
        return(0);
}


static int
iszerovec(const FVECT vec)
{
        return (vec[0] == 0.0) & (vec[1] == 0.0) & (vec[2] == 0.0);
}


static double
nextray(                /* return next ray in work group (-1.0 if EOF) */
        FVECT org,
        FVECT dir
)
{
        const size_t    qlength = !vresolu * hresolu;

        if ((org == NULL) | (dir == NULL)) {
                if (inp_queue != NULL)  /* asking to free queue */
                        free(inp_queue);
                inp_queue = NULL;
                inp_qpos = inp_qend = 0;
                return(-1.);
        }
        if (!inp_qend) {                /* initialize FIFO queue */
                int     rsiz = 6*20;    /* conservative ascii ray size */
                if (inform == 'f') rsiz = 6*sizeof(float);
                else if (inform == 'd') rsiz = 6*sizeof(double);
                                        /* check against pipe limit */
                if (qlength*rsiz > 512 && is_fifo(inpfp))
                        inp_queue = (FVECT *)malloc(sizeof(FVECT)*2*qlength);
                inp_qend = -(inp_queue == NULL);        /* flag for no queue */
        }
        if (inp_qend < 0) {             /* not queuing? */
                if (getvec(org, inform, inpfp) < 0 ||
                                getvec(dir, inform, inpfp) < 0)
                        return(-1.);
                return normalize(dir);
        }
        if (inp_qpos >= inp_qend) {     /* need to refill input queue? */
                for (inp_qend = 0; inp_qend < qlength; inp_qend++) {
                        if (getvec(inp_queue[2*inp_qend], inform, inpfp) < 0
                                        || getvec(inp_queue[2*inp_qend+1],
                                                        inform, inpfp) < 0)
                                break;          /* hit EOF */
                        if (iszerovec(inp_queue[2*inp_qend+1])) {
                                ++inp_qend;     /* flush request */
                                break;
                        }
                }
                inp_qpos = 0;
        }
        if (inp_qpos >= inp_qend)       /* unexpected EOF? */
                return(-1.);
        VCOPY(org, inp_queue[2*inp_qpos]);
        VCOPY(dir, inp_queue[2*inp_qpos+1]);
        ++inp_qpos;
        return normalize(dir);
}


void
tranotify(                      /* record new modifier */
        OBJECT  obj
)
{
        static int  hitlimit = 0;
        OBJREC   *o = objptr(obj);
        char  **tralp;

        if (obj == OVOID) {             /* starting over */
                traset[0] = 0;
                hitlimit = 0;
                return;
        }
        if (hitlimit || !ismodifier(o->otype))
                return;
        for (tralp = tralist; *tralp != NULL; tralp++)
                if (!strcmp(o->oname, *tralp)) {
                        if (traset[0] >= MAXTSET) {
                                error(WARNING, "too many modifiers in trace list");
                                hitlimit++;
                                return;         /* should this be fatal? */
                        }
                        insertelem(traset, obj);
                        return;
                }
}


static void
ourtrace(                               /* print ray values */
        RAY  *r
)
{
        oputf_t **tp;

        if (every_out[0] == NULL)
                return;
        if (r->ro == NULL) {
                if (traincl == 1)
                        return;
        } else if (traincl != -1 && traincl != inset(traset, r->ro->omod))
                return;
        tabin(r);
        for (tp = every_out; *tp != NULL; tp++)
                (**tp)(r);
        if (outform == 'a')
                putchar('\n');
}


static void
tabin(                          /* tab in appropriate amount */
        RAY  *r
)
{
        const RAY  *rp;

        for (rp = r->parent; rp != NULL; rp = rp->parent)
                putchar('\t');
}


static void
oputo(                          /* print origin */
        RAY  *r
)
{
        (*putreal)(r->rorg, 3);
}


static void
oputd(                          /* print direction */
        RAY  *r
)
{
        (*putreal)(r->rdir, 3);
}


static void
oputr(                          /* print mirrored contribution */
        RAY  *r
)
{
        RREAL   cval[3];

        cval[0] = colval(r->mcol,RED);
        cval[1] = colval(r->mcol,GRN);
        cval[2] = colval(r->mcol,BLU);
        (*putreal)(cval, 3);
}


static void
oputR(                          /* print mirrored distance */
        RAY  *r
)
{
        (*putreal)(&r->rmt, 1);
}


static void
oputx(                          /* print unmirrored contribution */
        RAY  *r
)
{
        RREAL   cval[3];

        cval[0] = colval(r->rcol,RED) - colval(r->mcol,RED);
        cval[1] = colval(r->rcol,GRN) - colval(r->mcol,GRN);
        cval[2] = colval(r->rcol,BLU) - colval(r->mcol,BLU);
        (*putreal)(cval, 3);
}


static void
oputX(                          /* print unmirrored distance */
        RAY  *r
)
{
        (*putreal)(&r->rxt, 1);
}


static void
oputv(                          /* print value */
        RAY  *r
)
{
        RREAL   cval[3];

        cval[0] = colval(r->rcol,RED);
        cval[1] = colval(r->rcol,GRN);
        cval[2] = colval(r->rcol,BLU);
        (*putreal)(cval, 3);
}


static void
oputV(                          /* print value contribution */
        RAY *r
)
{
        RREAL   contr[3];

        raycontrib(contr, r, PRIMARY);
        multcolor(contr, r->rcol);
        (*putreal)(contr, 3);
}


static void
oputl(                          /* print effective distance */
        RAY  *r
)
{
        RREAL   d = raydistance(r);

        (*putreal)(&d, 1);
}


static void
oputL(                          /* print single ray length */
        RAY  *r
)
{
        (*putreal)(&r->rot, 1);
}


static void
oputc(                          /* print local coordinates */
        RAY  *r
)
{
        (*putreal)(r->uv, 2);
}


static RREAL    vdummy[3] = {0.0, 0.0, 0.0};


static void
oputp(                          /* print intersection point */
        RAY  *r
)
{
        (*putreal)(r->rop, 3);  /* set to ray origin if distant or no hit */
}


static void
oputN(                          /* print unperturbed normal */
        RAY  *r
)
{
        if (r->ro == NULL) {    /* zero vector if clipped or no hit */
                (*putreal)(vdummy, 3);
                return;
        }
        if (r->rflips & 1) {    /* undo any flippin' flips */
                FVECT   unrm;
                unrm[0] = -r->ron[0];
                unrm[1] = -r->ron[1];
                unrm[2] = -r->ron[2];
                (*putreal)(unrm, 3);
        } else
                (*putreal)(r->ron, 3);
}


static void
oputn(                          /* print perturbed normal */
        RAY  *r
)
{
        FVECT  pnorm;

        if (r->ro == NULL) {    /* clipped or no hit */
                (*putreal)(vdummy, 3);
                return;
        }
        raynormal(pnorm, r);
        (*putreal)(pnorm, 3);
}


static void
oputs(                          /* print name */
        RAY  *r
)
{
        if (r->ro != NULL)
                fputs(r->ro->oname, stdout);
        else
                putchar('*');
        putchar('\t');
}


static void
oputw(                          /* print weight */
        RAY  *r
)
{
        RREAL   rwt = r->rweight;
        
        (*putreal)(&rwt, 1);
}


static void
oputW(                          /* print coefficient */
        RAY  *r
)
{
        RREAL   contr[3];
                                /* shadow ray not on source? */
        if (r->rsrc >= 0 && source[r->rsrc].so != r->ro)
                setcolor(contr, 0.0, 0.0, 0.0);
        else
                raycontrib(contr, r, PRIMARY);

        (*putreal)(contr, 3);
}


static void
oputm(                          /* print modifier */
        RAY  *r
)
{
        if (r->ro != NULL)
                if (r->ro->omod != OVOID)
                        fputs(objptr(r->ro->omod)->oname, stdout);
                else
                        fputs(VOIDID, stdout);
        else
                putchar('*');
        putchar('\t');
}


static void
oputM(                          /* print material */
        RAY  *r
)
{
        OBJREC  *mat;

        if (r->ro != NULL) {
                if ((mat = findmaterial(r->ro)) != NULL)
                        fputs(mat->oname, stdout);
                else
                        fputs(VOIDID, stdout);
        } else
                putchar('*');
        putchar('\t');
}


static void
oputtilde(                      /* output tilde (spacer) */
        RAY  *r
)
{
        fputs("~\t", stdout);
}


static void
puta(                           /* print ascii value(s) */
        RREAL *v, int n
)
{
        if (n == 3) {
                printf("%e\t%e\t%e\t", v[0], v[1], v[2]);
                return;
        }
        while (n--)
                printf("%e\t", *v++);
}


static void
putd(RREAL *v, int n)           /* output binary double(s) */
{
#ifdef  SMLFLT
        double  da[3];
        int     i;

        if (n > 3)
                error(INTERNAL, "code error in putd()");
        for (i = n; i--; )
                da[i] = v[i];
        putbinary(da, sizeof(double), n, stdout);
#else
        putbinary(v, sizeof(RREAL), n, stdout);
#endif
}


static void
putf(RREAL *v, int n)           /* output binary float(s) */
{
#ifndef SMLFLT
        float   fa[3];
        int     i;

        if (n > 3)
                error(INTERNAL, "code error in putf()");
        for (i = n; i--; )
                fa[i] = v[i];
        putbinary(fa, sizeof(float), n, stdout);
#else
        putbinary(v, sizeof(RREAL), n, stdout);
#endif
}


static void
putrgbe(RREAL *v, int n)        /* output RGBE color */
{
        COLR  cout;

        if (n != 3)
                error(INTERNAL, "putrgbe() not called with 3 components");
        setcolr(cout, v[0], v[1], v[2]);
        putbinary(cout, sizeof(cout), 1, stdout);
}
Revision:	2.103
Committed:	Sun Apr 24 15:40:33 2022 UTC (3 years, 6 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.102:	+12 -12 lines
Log Message:	fix(rtrace): Fixed segmentation violation introduced in 2.93 (Apr 2020)