src/px/x11image.c

/* Copyright (c) 1991 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 *  x11image.c - driver for X-windows
 *
 *     3/1/90
 */

/*
 *  Modified for X11
 *
 *  January 1990
 *
 *  Anat Grynberg  and Greg Ward
 */


#include  "standard.h"

#include  <X11/Xlib.h>
#include  <X11/cursorfont.h>
#include  <X11/Xutil.h>

#include  "color.h"
#include  "view.h"
#include  "pic.h"
#include  "x11raster.h"
#include  "random.h"
#include  "resolu.h"

#define  FONTNAME       "8x13"          /* text font we'll use */

#define  CTRL(c)        ((c)-'@')

#define  BORWIDTH       5               /* border width */

#define  ICONSIZ        (8*10)          /* maximum icon dimension (even 8) */

#define  ourscreen      DefaultScreen(thedisplay)
#define  ourblack       BlackPixel(thedisplay,ourscreen)
#define  ourwhite       WhitePixel(thedisplay,ourscreen)
#define  ourroot        RootWindow(thedisplay,ourscreen)

#define  revline(x0,y0,x1,y1)   XDrawLine(thedisplay,wind,revgc,x0,y0,x1,y1)

#define  redraw(x,y,w,h) patch_raster(wind,(x)-xoff,(y)-yoff,x,y,w,h,ourras)

double  gamcor = 2.2;                   /* gamma correction */

int  dither = 1;                        /* dither colors? */
int  fast = 0;                          /* keep picture in Pixmap? */

char    *dispname = NULL;               /* our display name */

Window  wind = 0;                       /* our output window */
Font  fontid;                           /* our font */

int  maxcolors = 0;                     /* maximum colors */
int  greyscale = 0;                     /* in grey */

int  scale = 0;                         /* scalefactor; power of two */

int  xoff = 0;                          /* x image offset */
int  yoff = 0;                          /* y image offset */

VIEW  ourview = STDVIEW;                /* image view parameters */
int  gotview = 0;                       /* got parameters from file */

COLR  *scanline;                        /* scan line buffer */

RESOLU  inpres;                         /* input resolution and ordering */
int  xmax, ymax;                        /* picture dimensions */
int  width, height;                     /* window size */
char  *fname = NULL;                    /* input file name */
FILE  *fin = stdin;                     /* input file */
long  *scanpos = NULL;                  /* scan line positions in file */
int  cury = 0;                          /* current scan location */

double  exposure = 1.0;                 /* exposure compensation used */

int  wrongformat = 0;                   /* input in another format? */

GC      ourgc;                          /* standard graphics context */
GC      revgc;                          /* graphics context with GXinvert */

int             *ourrank;               /* our visual class ranking */
XVisualInfo     ourvis;                 /* our visual */
XRASTER         *ourras;                /* our stored image */
unsigned char   *ourdata;               /* our image data */

struct {
        int  xmin, ymin, xsiz, ysiz;
}  box = {0, 0, 0, 0};                  /* current box */

char  *geometry = NULL;                 /* geometry specification */

char  icondata[ICONSIZ*ICONSIZ/8];      /* icon bitmap data */
int  iconwidth = 0, iconheight = 0;

char  *progname;

char  errmsg[128];

extern long  ftell();

extern char  *malloc(), *calloc();

extern double  pow(), log();

Display  *thedisplay;

main(argc, argv)
int  argc;
char  *argv[];
{
        int  headline();
        int  i;
        
        progname = argv[0];

        for (i = 1; i < argc; i++)
                if (argv[i][0] == '-')
                        switch (argv[i][1]) {
                        case 'c':
                                maxcolors = atoi(argv[++i]);
                                break;
                        case 'b':
                                greyscale = !greyscale;
                                break;
                        case 'm':
                                maxcolors = 2;
                                break;
                        case 'd':
                                if (argv[i][2] == 'i')
                                        dispname = argv[++i];
                                else
                                        dither = !dither;
                                break;
                        case 'f':
                                fast = !fast;
                                break;
                        case 'e':
                                if (argv[i+1][0] != '+' && argv[i+1][0] != '-')
                                        goto userr;
                                scale = atoi(argv[++i]);
                                break;
                        case 'g':
                                if (argv[i][2] == 'e')
                                        geometry = argv[++i];
                                else
                                        gamcor = atof(argv[++i]);
                                break;
                        default:
                                goto userr;
                        }
                else if (argv[i][0] == '=')
                        geometry = argv[i];
                else
                        break;

        if (i == argc-1) {
                fname = argv[i];
                fin = fopen(fname, "r");
                if (fin == NULL) {
                        sprintf(errmsg, "cannot open file \"%s\"", fname);
                        quiterr(errmsg);
                }
        } else if (i != argc)
                goto userr;
                                /* get header */
        getheader(fin, headline, NULL);
                                /* get picture dimensions */
        if (wrongformat || !fgetsresolu(&inpres, fin))
                quiterr("bad picture format");
        xmax = scanlen(&inpres);
        ymax = numscans(&inpres);
                                /* set view parameters */
        if (gotview && setview(&ourview) != NULL)
                gotview = 0;
        if ((scanline = (COLR *)malloc(xmax*sizeof(COLR))) == NULL)
                quiterr("out of memory");

        init();                 /* get file and open window */

        for ( ; ; )
                getevent();             /* main loop */
userr:
        fprintf(stderr,
        "Usage: %s [-display disp][-geometry spec][-b][-m][-d][-f][-c ncolors][-e +/-stops] file\n",
                        progname);
        quit(1);
}


headline(s)             /* get relevant info from header */
char  *s;
{
        char  fmt[32];

        if (isexpos(s))
                exposure *= exposval(s);
        else if (isformat(s)) {
                formatval(fmt, s);
                wrongformat = strcmp(fmt, COLRFMT);
        } else if (isview(s) && sscanview(&ourview, s) > 0)
                gotview++;
}


init()                  /* get data and open window */
{
        XWMHints        ourxwmhints;
        XSetWindowAttributes    ourwinattr;
        XSizeHints      oursizhints;
        register int    i;
        
        if (fname != NULL) {
                scanpos = (long *)malloc(ymax*sizeof(long));
                if (scanpos == NULL)
                        goto memerr;
                for (i = 0; i < ymax; i++)
                        scanpos[i] = -1;
        }
        if ((thedisplay = XOpenDisplay(dispname)) == NULL)
                quiterr("cannot open display");
                                /* get best visual for default screen */
        getbestvis();
                                /* store image */
        getras();
                                /* open window */
        ourwinattr.border_pixel = ourblack;
        ourwinattr.background_pixel = ourwhite;
        ourwinattr.colormap = XCreateColormap(thedisplay, ourroot,
                        ourvis.visual, AllocNone);
        wind = XCreateWindow(thedisplay, ourroot, 0, 0, xmax, ymax, BORWIDTH,
                        ourvis.depth, InputOutput, ourvis.visual, 
                        CWBackPixel|CWBorderPixel|CWColormap, &ourwinattr);
        if (wind == 0)
                quiterr("cannot create window");
        width = xmax;
        height = ymax;
        ourgc = XCreateGC(thedisplay, wind, 0, 0);
        XSetState(thedisplay, ourgc, BlackPixel(thedisplay,ourscreen),
                        WhitePixel(thedisplay,ourscreen), GXcopy, AllPlanes);
        revgc = XCreateGC(thedisplay, wind, 0, 0);
        XSetFunction(thedisplay, revgc, GXinvert);
        fontid = XLoadFont(thedisplay, FONTNAME);
        if (fontid == 0)
                quiterr("cannot get font");
        XSetFont(thedisplay, ourgc, fontid);
        XDefineCursor(thedisplay, wind, XCreateFontCursor(thedisplay, 
                        XC_diamond_cross));
        XStoreName(thedisplay, wind, fname == NULL ? progname : fname);
        if (geometry != NULL) {
                bzero((char *)&oursizhints, sizeof(oursizhints));
                i = XParseGeometry(geometry, &oursizhints.x, &oursizhints.y,
                                (unsigned *)&oursizhints.width,
                                (unsigned *)&oursizhints.height);
                if ((i&(WidthValue|HeightValue)) == (WidthValue|HeightValue))
                        oursizhints.flags |= USSize;
                else {
                        oursizhints.width = xmax;
                        oursizhints.height = ymax;
                        oursizhints.flags |= PSize;
                }
                if ((i&(XValue|YValue)) == (XValue|YValue)) {
                        oursizhints.flags |= USPosition;
                        if (i & XNegative)
                                oursizhints.x += DisplayWidth(thedisplay,
                                ourscreen)-1-oursizhints.width-2*BORWIDTH;
                        if (i & YNegative)
                                oursizhints.y += DisplayHeight(thedisplay,
                                ourscreen)-1-oursizhints.height-2*BORWIDTH;
                }
                XSetNormalHints(thedisplay, wind, &oursizhints);
        }
        ourxwmhints.flags = InputHint|IconPixmapHint;
        ourxwmhints.input = True;
        ourxwmhints.icon_pixmap = XCreateBitmapFromData(thedisplay,
                        wind, icondata, iconwidth, iconheight);
        XSetWMHints(thedisplay, wind, &ourxwmhints);
        XSelectInput(thedisplay, wind, ButtonPressMask|ButtonReleaseMask
                        |ButtonMotionMask|StructureNotifyMask
                        |KeyPressMask|ExposureMask);
        XMapWindow(thedisplay, wind);
        return;
memerr:
        quiterr("out of memory");
} /* end of init */


quiterr(err)            /* print message and exit */
char  *err;
{
        if (err != NULL) {
                fprintf(stderr, "%s: %s\n", progname, err);
                exit(1);
        }
        exit(0);
}


eputs(s)
char    *s;
{
        fputs(s, stderr);
}


quit(code)
int  code;
{
        exit(code);
}


static int
viscmp(v1,v2)           /* compare visual to see which is better, descending */
register XVisualInfo    *v1, *v2;
{
        int     bad1 = 0, bad2 = 0;
        register int  *rp;

        if (v1->class == v2->class) {
                if (v1->class == TrueColor || v1->class == DirectColor) {
                                        /* prefer 24-bit to 32-bit */
                        if (v1->depth == 24 && v2->depth == 32)
                                return(-1);
                        if (v1->depth == 32 && v2->depth == 24)
                                return(1);
                        return(0);
                }
                                        /* don't be too greedy */
                if (maxcolors <= 1<<v1->depth && maxcolors <= 1<<v2->depth)
                        return(v1->depth - v2->depth);
                return(v2->depth - v1->depth);
        }
                                        /* prefer Pseudo when < 24-bit */
        if ((v1->class == TrueColor || v1->class == DirectColor) &&
                        v1->depth < 24)
                bad1 = 1;
        if ((v2->class == TrueColor || v2->class == DirectColor) &&
                        v2->depth < 24)
                bad2 = -1;
        if (bad1 | bad2)
                return(bad1+bad2);
                                        /* otherwise, use class ranking */
        for (rp = ourrank; *rp != -1; rp++) {
                if (v1->class == *rp)
                        return(-1);
                if (v2->class == *rp)
                        return(1);
        }
        return(0);
}


getbestvis()                    /* get the best visual for this screen */
{
#ifdef DEBUG
static char  vistype[][12] = {
                "StaticGray",
                "GrayScale",
                "StaticColor",
                "PseudoColor",
                "TrueColor",
                "DirectColor"
};
#endif
        static int      rankings[3][6] = {
                {TrueColor,DirectColor,PseudoColor,GrayScale,StaticGray,-1},
                {PseudoColor,GrayScale,StaticGray,-1},
                {PseudoColor,GrayScale,StaticGray,-1}
        };
        XVisualInfo     *xvi;
        int     vismatched;
        register int    i, j;

        if (greyscale) {
                ourrank = rankings[2];
                if (maxcolors < 2) maxcolors = 256;
        } else if (maxcolors >= 2 && maxcolors <= 256)
                ourrank = rankings[1];
        else {
                ourrank = rankings[0];
                maxcolors = 256;
        }
                                        /* find best visual */
        ourvis.screen = ourscreen;
        xvi = XGetVisualInfo(thedisplay,VisualScreenMask,&ourvis,&vismatched);
        if (xvi == NULL)
                quiterr("no visuals for this screen!");
#ifdef DEBUG
        fprintf(stderr, "Supported visuals:\n");
        for (i = 0; i < vismatched; i++)
                fprintf(stderr, "\ttype %s, depth %d\n",
                                vistype[xvi[i].class], xvi[i].depth);
#endif
        for (i = 0, j = 1; j < vismatched; j++)
                if (viscmp(&xvi[i],&xvi[j]) > 0)
                        i = j;
                                        /* compare to least acceptable */
        for (j = 0; ourrank[j++] != -1; )
                ;
        ourvis.class = ourrank[--j];
        ourvis.depth = 1;
        if (viscmp(&xvi[i],&ourvis) > 0)
                quiterr("inadequate visuals on this screen");
                                        /* OK, we'll use it */
        copystruct(&ourvis, &xvi[i]);
#ifdef DEBUG
        fprintf(stderr, "Selected visual type %s, depth %d\n",
                        vistype[ourvis.class], ourvis.depth);
#endif
        if (ourvis.class == GrayScale || ourvis.class == StaticGray)
                greyscale = 1;
        if (ourvis.depth <= 8 && ourvis.colormap_size < maxcolors)
                maxcolors = ourvis.colormap_size;
        if (maxcolors > 4)
                maxcolors -= 2;
        XFree((char *)xvi);
}


getras()                                /* get raster file */
{
        colormap        ourmap;
        XVisualInfo     vinfo;

        if (maxcolors <= 2) {           /* monochrome */
                ourdata = (unsigned char *)malloc(ymax*((xmax+7)/8));
                if (ourdata == NULL)
                        goto fail;
                ourras = make_raster(thedisplay, &ourvis, 1, ourdata,
                                xmax, ymax, 8);
                if (ourras == NULL)
                        goto fail;
                getmono();
        } else if (ourvis.class == TrueColor || ourvis.class == DirectColor) {
                ourdata = (unsigned char *)malloc(4*xmax*ymax);
                if (ourdata == NULL)
                        goto fail;
                ourras = make_raster(thedisplay, &ourvis, 32,
                                ourdata, xmax, ymax, 32);
                if (ourras == NULL)
                        goto fail;
                getfull();
        } else {
                ourdata = (unsigned char *)malloc(xmax*ymax);
                if (ourdata == NULL)
                        goto fail;
                ourras = make_raster(thedisplay, &ourvis, 8, ourdata,
                                xmax, ymax, 8);
                if (ourras == NULL)
                        goto fail;
                if (ourvis.class == StaticGray)
                        getgrey();
                else {
                        if (greyscale)
                                biq(dither,maxcolors,1,ourmap);
                        else
                                ciq(dither,maxcolors,1,ourmap);
                        if (init_rcolors(ourras, ourmap[0],
                                        ourmap[1], ourmap[2]) == 0)
                                goto fail;
                }
        }
                return;
fail:
        quiterr("could not create raster image");
}


getevent()                              /* process the next event */
{
        union {
                XEvent  u;
                XConfigureEvent  c;
                XExposeEvent  e;
                XButtonPressedEvent  b;
                XKeyPressedEvent  k;
        } e;

        XNextEvent(thedisplay, &e.u);
        switch (e.u.type) {
        case KeyPress:
                docom(&e.k);
                break;
        case ConfigureNotify:
                width = e.c.width;
                height = e.c.height;
                break;
        case MapNotify:
                map_rcolors(ourras, wind);
                if (fast)
                        make_rpixmap(ourras, wind);
                break;
        case UnmapNotify:
                if (!fast)
                        unmap_rcolors(ourras);
                break;
        case Expose:
                redraw(e.e.x, e.e.y, e.e.width, e.e.height);
                break;
        case ButtonPress:
                if (e.b.state & (ShiftMask|ControlMask))
                        moveimage(&e.b);
                else
                        getbox(&e.b);
                break;
        }
}


docom(ekey)                                     /* execute command */
XKeyPressedEvent  *ekey;
{
        char  buf[80];
        COLOR  cval;
        XColor  cvx;
        int  com, n;
        double  comp;
        FLOAT  hv[2];
        FVECT  rorg, rdir;

        n = XLookupString(ekey, buf, sizeof(buf), NULL, NULL); 
        if (n == 0)
                return(0);
        com = buf[0];
        switch (com) {                  /* interpret command */
        case 'q':
        case CTRL('D'):                         /* quit */
                quit(0);
        case '\n':
        case '\r':
        case 'l':
        case 'c':                               /* value */
                if (avgbox(cval) == -1)
                        return(-1);
                switch (com) {
                case '\n':
                case '\r':                              /* radiance */
                        sprintf(buf, "%.3f", intens(cval)/exposure);
                        break;
                case 'l':                               /* luminance */
                        sprintf(buf, "%.0fL", luminance(cval)/exposure);
                        break;
                case 'c':                               /* color */
                        comp = pow(2.0, (double)scale);
                        sprintf(buf, "(%.2f,%.2f,%.2f)",
                                        colval(cval,RED)*comp,
                                        colval(cval,GRN)*comp,
                                        colval(cval,BLU)*comp);
                        break;
                }
                XDrawImageString(thedisplay, wind, ourgc,
                                box.xmin, box.ymin+box.ysiz, buf, strlen(buf)); 
                return(0);
        case 'i':                               /* identify (contour) */
                if (ourras->pixels == NULL)
                        return(-1);
                n = ourdata[ekey->x-xoff+xmax*(ekey->y-yoff)];
                n = ourras->pmap[n];
                cvx.pixel = ourras->cdefs[n].pixel;
                cvx.red = random() & 65535;
                cvx.green = random() & 65535;
                cvx.blue = random() & 65535;
                cvx.flags = DoRed|DoGreen|DoBlue;
                XStoreColor(thedisplay, ourras->cmap, &cvx);
                return(0);
        case 'p':                               /* position */
                pix2loc(hv, &inpres, ekey->x-xoff, ekey->y-yoff);
                sprintf(buf, "(%d,%d)", (int)(hv[0]*inpres.xr),
                                (int)(hv[1]*inpres.yr));
                XDrawImageString(thedisplay, wind, ourgc, ekey->x, ekey->y,
                                        buf, strlen(buf));
                return(0);
        case 't':                               /* trace */
                if (!gotview) {
                        XBell(thedisplay, 0);
                        return(-1);
                }
                pix2loc(hv, &inpres, ekey->x-xoff, ekey->y-yoff);
                if (viewray(rorg, rdir, &ourview, hv[0], hv[1]) < 0)
                        return(-1);
                printf("%e %e %e ", rorg[0], rorg[1], rorg[2]);
                printf("%e %e %e\n", rdir[0], rdir[1], rdir[2]);
                fflush(stdout);
                return(0);
        case '=':                               /* adjust exposure */
                if (avgbox(cval) == -1)
                        return(-1);
                n = log(.5/bright(cval))/.69315 - scale;        /* truncate */
                if (n == 0)
                        return(0);
                scale_rcolors(ourras, pow(2.0, (double)n));
                scale += n;
                sprintf(buf, "%+d", scale);
                XDrawImageString(thedisplay, wind, ourgc,
                                box.xmin, box.ymin+box.ysiz, buf, strlen(buf));
                XFlush(thedisplay);
                free(ourdata);
                free_raster(ourras);
                getras();
        /* fall through */
        case CTRL('R'):                         /* redraw */
        case CTRL('L'):
                unmap_rcolors(ourras);
                XClearWindow(thedisplay, wind);
                map_rcolors(ourras, wind);
                if (fast)
                        make_rpixmap(ourras);
                redraw(0, 0, width, height);
                return(0);
        case ' ':                               /* clear */
                redraw(box.xmin, box.ymin, box.xsiz, box.ysiz);
                return(0);
        default:
                XBell(thedisplay, 0);
                return(-1);
        }
}


moveimage(ebut)                         /* shift the image */
XButtonPressedEvent  *ebut;
{
        union {
                XEvent  u;
                XButtonReleasedEvent  b;
                XPointerMovedEvent  m;
        }  e;
        int     mxo, myo;

        XMaskEvent(thedisplay, ButtonReleaseMask|ButtonMotionMask, &e.u);
        while (e.u.type == MotionNotify) {
                mxo = e.m.x;
                myo = e.m.y;
                revline(ebut->x, ebut->y, mxo, myo);
                revbox(xoff+mxo-ebut->x, yoff+myo-ebut->y,
                                xoff+mxo-ebut->x+xmax, yoff+myo-ebut->y+ymax);
                XMaskEvent(thedisplay,ButtonReleaseMask|ButtonMotionMask,&e.u);
                revline(ebut->x, ebut->y, mxo, myo);
                revbox(xoff+mxo-ebut->x, yoff+myo-ebut->y,
                                xoff+mxo-ebut->x+xmax, yoff+myo-ebut->y+ymax);
        }
        xoff += e.b.x - ebut->x;
        yoff += e.b.y - ebut->y;
        XClearWindow(thedisplay, wind);
        redraw(0, 0, width, height);
}


getbox(ebut)                            /* get new box */
XButtonPressedEvent  *ebut;
{
        union {
                XEvent  u;
                XButtonReleasedEvent  b;
                XPointerMovedEvent  m;
        }  e;

        XMaskEvent(thedisplay, ButtonReleaseMask|ButtonMotionMask, &e.u);
        while (e.u.type == MotionNotify) {
                revbox(ebut->x, ebut->y, box.xmin = e.m.x, box.ymin = e.m.y);
                XMaskEvent(thedisplay,ButtonReleaseMask|ButtonMotionMask,&e.u);
                revbox(ebut->x, ebut->y, box.xmin, box.ymin);
        }
        box.xmin = e.b.x<0 ? 0 : (e.b.x>=width ? width-1 : e.b.x);
        box.ymin = e.b.y<0 ? 0 : (e.b.y>=height ? height-1 : e.b.y);
        if (box.xmin > ebut->x) {
                box.xsiz = box.xmin - ebut->x + 1;
                box.xmin = ebut->x;
        } else {
                box.xsiz = ebut->x - box.xmin + 1;
        }
        if (box.ymin > ebut->y) {
                box.ysiz = box.ymin - ebut->y + 1;
                box.ymin = ebut->y;
        } else {
                box.ysiz = ebut->y - box.ymin + 1;
        }
}


revbox(x0, y0, x1, y1)                  /* draw box with reversed lines */
int  x0, y0, x1, y1;
{
        revline(x0, y0, x1, y0);
        revline(x0, y1, x1, y1);
        revline(x0, y0, x0, y1);
        revline(x1, y0, x1, y1);
}


avgbox(clr)                             /* average color over current box */
COLOR  clr;
{
        static COLOR  lc;
        static int  ll, lr, lt, lb;
        int  left, right, top, bottom;
        int  y;
        double  d;
        COLOR  ctmp;
        register int  x;

        setcolor(clr, 0.0, 0.0, 0.0);
        left = box.xmin - xoff;
        right = left + box.xsiz;
        if (left < 0)
                left = 0;
        if (right > xmax)
                right = xmax;
        if (left >= right)
                return(-1);
        top = box.ymin - yoff;
        bottom = top + box.ysiz;
        if (top < 0)
                top = 0;
        if (bottom > ymax)
                bottom = ymax;
        if (top >= bottom)
                return(-1);
        if (left == ll && right == lr && top == lt && bottom == lb) {
                copycolor(clr, lc);
                return;
        }
        for (y = top; y < bottom; y++) {
                if (getscan(y) == -1)
                        return(-1);
                for (x = left; x < right; x++) {
                        colr_color(ctmp, scanline[x]);
                        addcolor(clr, ctmp);
                }
        }
        d = 1.0/((right-left)*(bottom-top));
        scalecolor(clr, d);
        ll = left; lr = right; lt = top; lb = bottom;
        copycolor(lc, clr);
        return(0);
}


getmono()                       /* get monochrome data */
{
        register unsigned char  *dp;
        register int    x, err;
        int     y, errp;
        short   *cerr;

        if ((cerr = (short *)calloc(xmax,sizeof(short))) == NULL)
                quiterr("out of memory in getmono");
        dp = ourdata - 1;
        for (y = 0; y < ymax; y++) {
                if (getscan(y) < 0)
                        quiterr("seek error in getmono");
                normcolrs(scanline, xmax, scale);
                add2icon(y, scanline);
                err = 0;
                for (x = 0; x < xmax; x++) {
                        if (!(x&7))
                                *++dp = 0;
                        errp = err;
                        err += normbright(scanline[x]) + cerr[x];
                        if (err > 127)
                                err -= 255;
                        else
                                *dp |= 1<<(7-(x&07));
                        err /= 3;
                        cerr[x] = err + errp;
                }
        }
        free((char *)cerr);
}


add2icon(y, scan)               /* add a scanline to our icon data */
int  y;
COLR  *scan;
{
        static short  cerr[ICONSIZ];
        static int  ynext;
        static char  *dp;
        register int  err;
        register int    x, ti;
        int  errp;

        if (iconheight == 0) {          /* initialize */
                if (xmax <= ICONSIZ && ymax <= ICONSIZ) {
                        iconwidth = xmax;
                        iconheight = ymax;
                } else if (xmax > ymax) {
                        iconwidth = ICONSIZ;
                        iconheight = ICONSIZ*ymax/xmax;
                        if (iconheight < 1)
                                iconheight = 1;
                } else {
                        iconwidth = ICONSIZ*xmax/ymax;
                        if (iconwidth < 1)
                                iconwidth = 1;
                        iconheight = ICONSIZ;
                }
                ynext = 0;
                dp = icondata - 1;
        }
        if (y < ynext*ymax/iconheight)  /* skip this one */
                return;
        err = 0;
        for (x = 0; x < iconwidth; x++) {
                if (!(x&7))
                        *++dp = 0;
                errp = err;
                ti = x*xmax/iconwidth;
                err += normbright(scan[ti]) + cerr[x];
                if (err > 127)
                        err -= 255;
                else
                        *dp |= 1<<(x&07);
                err /= 3;
                cerr[x] = err + errp;
        }
        ynext++;
}


getfull()                       /* get full (24-bit) data */
{
        int     y;
        register unsigned long  *dp;
        register int    x;
                                        /* set gamma correction */
        setcolrgam(gamcor);
                                        /* read and convert file */
        dp = (unsigned long *)ourdata;
        for (y = 0; y < ymax; y++) {
                if (getscan(y) < 0)
                        quiterr("seek error in getfull");
                if (scale)
                        shiftcolrs(scanline, xmax, scale);
                colrs_gambs(scanline, xmax);
                add2icon(y, scanline);
                if (ourras->image->blue_mask & 1)
                        for (x = 0; x < xmax; x++)
                                *dp++ = scanline[x][RED] << 16 |
                                        scanline[x][GRN] << 8 |
                                        scanline[x][BLU] ;
                else
                        for (x = 0; x < xmax; x++)
                                *dp++ = scanline[x][RED] |
                                        scanline[x][GRN] << 8 |
                                        scanline[x][BLU] << 16 ;
        }
}


getgrey()                       /* get greyscale data */
{
        int     y;
        register unsigned char  *dp;
        register int    x;
                                        /* set gamma correction */
        setcolrgam(gamcor);
                                        /* read and convert file */
        dp = ourdata;
        for (y = 0; y < ymax; y++) {
                if (getscan(y) < 0)
                        quiterr("seek error in getfull");
                if (scale)
                        shiftcolrs(scanline, xmax, scale);
                colrs_gambs(scanline, xmax);
                add2icon(y, scanline);
                if (ourvis.colormap_size < 256)
                        for (x = 0; x < xmax; x++)
                                *dp++ = ((long)normbright(scanline[x]) *
                                        ourvis.colormap_size + 128) >> 8;
                else
                        for (x = 0; x < xmax; x++)
                                *dp++ = normbright(scanline[x]);
        }
}


scale_rcolors(xr, sf)                   /* scale color map */
register XRASTER        *xr;
double  sf;
{
        register int    i;
        long    maxv;

        if (xr->pixels == NULL)
                return;

        sf = pow(sf, 1.0/gamcor);
        maxv = 65535/sf;

        for (i = xr->ncolors; i--; ) {
                xr->cdefs[i].red = xr->cdefs[i].red > maxv ?
                                65535 :
                                xr->cdefs[i].red * sf;
                xr->cdefs[i].green = xr->cdefs[i].green > maxv ?
                                65535 :
                                xr->cdefs[i].green * sf;
                xr->cdefs[i].blue = xr->cdefs[i].blue > maxv ?
                                65535 :
                                xr->cdefs[i].blue * sf;
        }
        XStoreColors(thedisplay, xr->cmap, xr->cdefs, xr->ncolors);
}


getscan(y)
int  y;
{
        if (y != cury) {
                if (scanpos == NULL || scanpos[y] == -1)
                        return(-1);
                if (fseek(fin, scanpos[y], 0) == -1)
                        quiterr("fseek error");
                cury = y;
        } else if (scanpos != NULL)
                scanpos[y] = ftell(fin);

        if (freadcolrs(scanline, xmax, fin) < 0)
                quiterr("read error");

        cury++;
        return(0);
}


picreadline3(y, l3)                     /* read in 3-byte scanline */
int  y;
register rgbpixel  *l3;
{
        register int    i;
                                                        /* read scanline */
        if (getscan(y) < 0)
                quiterr("cannot seek for picreadline");
                                                        /* convert scanline */
        normcolrs(scanline, xmax, scale);
        add2icon(y, scanline);
        for (i = 0; i < xmax; i++) {
                l3[i].r = scanline[i][RED];
                l3[i].g = scanline[i][GRN];
                l3[i].b = scanline[i][BLU];
        }
}


picwriteline(y, l)              /* add 8-bit scanline to image */
int  y;
pixel  *l;
{
        bcopy((char *)l, (char *)ourdata+y*xmax, xmax);
}


picreadcm(map)                  /* do gamma correction */
colormap  map;
{
        extern double  pow();
        register int  i, val;

        for (i = 0; i < 256; i++) {
                val = pow((i+0.5)/256.0, 1.0/gamcor) * 256.0;
                map[0][i] = map[1][i] = map[2][i] = val;
        }
}


picwritecm(map)                 /* handled elsewhere */
colormap  map;
{
#if 0
        register int i;

        for (i = 0; i < 256; i++)
                printf("%d %d %d\n", map[0][i],map[1][i],map[2][i]);
#endif
}
Revision:	2.7
Committed:	Thu May 28 09:43:09 1992 UTC (31 years, 11 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.6:	+63 -23 lines
Log Message:	further refinements for grayscale and odd devices