src/hd/rhd_glx.c

/* Copyright (c) 1997 Silicon Graphics, Inc. */

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

/*
 * OpenGL GLX driver for holodeck display.
 * Based on x11 driver.
 */

#include "standard.h"
#include "rhd_qtree.h"

#include  <GL/glx.h>

#include  "x11icon.h"

#ifndef RAYQLEN
#define RAYQLEN         50000           /* max. rays to queue before flush */
#endif

#ifndef FEQ
#define FEQ(a,b)        ((a)-(b) <= FTINY && (a)-(b) >= -FTINY)
#endif

#ifndef MAXCONE
#define MAXCONE         16              /* number of different cone sizes */
#endif
#ifndef MAXVERT
#define MAXVERT         32              /* maximum number of cone vertices */
#endif
#ifndef MINVERT
#define MINVERT         4               /* minimum number of cone vertices */
#endif
#ifndef DEPTHFACT
#define DEPTHFACT       16.             /* multiplier for depth tests */
#endif

#define GAMMA           1.4             /* default gamma correction */

#define MOVPCT          7               /* percent distance to move /frame */
#define MOVDIR(b)       ((b)==Button1 ? 1 : (b)==Button2 ? 0 : -1)
#define MOVDEG          (-5)            /* degrees to orbit CW/down /frame */
#define MOVORB(s)       ((s)&ShiftMask ? 1 : (s)&ControlMask ? -1 : 0)

#define MINWIDTH        480             /* minimum graphics window width */
#define MINHEIGHT       400             /* minimum graphics window height */

#define VIEWDIST        356             /* assumed viewing distance (mm) */

#define BORWIDTH        5               /* border width */

#define  ourscreen      DefaultScreen(ourdisplay)
#define  ourroot        RootWindow(ourdisplay,ourscreen)
#define  ourmask        (StructureNotifyMask|ExposureMask|KeyPressMask|\
                        ButtonPressMask|ButtonReleaseMask)

#define  levptr(etype)  ((etype *)&currentevent)

struct driver   odev;                   /* global device driver structure */

static XEvent  currentevent;            /* current event */

static int  mapped = 0;                 /* window is mapped? */
static unsigned long  ourblack=0, ourwhite=~0;

static Display  *ourdisplay = NULL;     /* our display */
static XVisualInfo  *ourvinf;           /* our visual information */
static Window  gwind = 0;               /* our graphics window */
static GLXContext       gctx;           /* our GLX context */

static double   pwidth, pheight;        /* pixel dimensions (mm) */

static double   curzmax = 1e4;          /* current depth upper limit */
static double   nxtzmax = 0.;           /* maximum (finite) depth so far */

static struct {
        double  rad;            /* cone radius */
        int     nverts;         /* number of vertices */
        FVECT   *va;            /* allocated vertex array */
} cone[MAXCONE];        /* precomputed cones for drawing */

static int      inpresflags;            /* input result flags */

static int      headlocked = 0;         /* lock vertical motion */

static int  resizewindow(), getevent(), getkey(), moveview(),
                initcones(), freecones(),
                getmove(), fixwindow(), mytmflags();


dev_open(id)                    /* initialize X11 driver */
char  *id;
{
        extern char     *getenv();
        static int      atlBest[] = {GLX_RGBA, GLX_RED_SIZE,8,
                                GLX_GREEN_SIZE,8, GLX_BLUE_SIZE,8,
                                GLX_DEPTH_SIZE,15, None};
        char    *gv;
        double  gamval = GAMMA;
        XSetWindowAttributes    ourwinattr;
        XWMHints        ourxwmhints;
        XSizeHints      oursizhints;
                                        /* set quadtree globals */
        qtMinNodesiz = 3;
        qtDepthEps = 0.07;
                                        /* open display server */
        ourdisplay = XOpenDisplay(NULL);
        if (ourdisplay == NULL)
                error(USER, "cannot open X-windows; DISPLAY variable set?\n");
                                        /* find a usable visual */
        ourvinf = glXChooseVisual(ourdisplay, ourscreen, atlBest);
        if (ourvinf == NULL)
                error(USER, "no suitable visuals available");
                                        /* get a context */
        gctx = glXCreateContext(ourdisplay, ourvinf, NULL, GL_TRUE);
                                        /* set gamma and tone mapping */
        if ((gv = XGetDefault(ourdisplay, "radiance", "gamma")) != NULL
                        || (gv = getenv("DISPLAY_GAMMA")) != NULL)
                gamval = atof(gv);
        if (tmInit(mytmflags(), stdprims, gamval) == NULL)
                error(SYSTEM, "not enough memory in dev_open");
                                        /* open window */
        ourwinattr.background_pixel = ourblack;
        ourwinattr.border_pixel = ourblack;
        ourwinattr.event_mask = ourmask;
                                        /* this is stupid */
        ourwinattr.colormap = XCreateColormap(ourdisplay, ourroot,
                                ourvinf->visual, AllocNone);
        gwind = XCreateWindow(ourdisplay, ourroot, 0, 0,
                DisplayWidth(ourdisplay,ourscreen)-2*BORWIDTH,
                DisplayHeight(ourdisplay,ourscreen)-2*BORWIDTH,
                BORWIDTH, ourvinf->depth, InputOutput, ourvinf->visual,
                CWBackPixel|CWBorderPixel|CWColormap|CWEventMask, &ourwinattr);
        if (gwind == 0)
                error(SYSTEM, "cannot create window\n");
        XStoreName(ourdisplay, gwind, id);
                                        /* set window manager hints */
        ourxwmhints.flags = InputHint|IconPixmapHint;
        ourxwmhints.input = True;
        ourxwmhints.icon_pixmap = XCreateBitmapFromData(ourdisplay,
                        gwind, x11icon_bits, x11icon_width, x11icon_height);
        XSetWMHints(ourdisplay, gwind, &ourxwmhints);
        oursizhints.min_width = MINWIDTH;
        oursizhints.min_height = MINHEIGHT;
        oursizhints.flags = PMinSize;
        XSetNormalHints(ourdisplay, gwind, &oursizhints);
                                        /* set GLX context */
        glXMakeCurrent(ourdisplay, gwind, gctx);
        glEnable(GL_DEPTH_TEST);
        glDepthFunc(GL_LEQUAL);
        glShadeModel(GL_FLAT);
        glDisable(GL_DITHER);
        glDisable(GL_CULL_FACE);
        glMatrixMode(GL_PROJECTION);
        glOrtho(0., 1., 0., 1., -.01, 1.01);
        glTranslated(0., 0., -1.01);
                                        /* figure out sensible view */
        pwidth = (double)DisplayWidthMM(ourdisplay, ourscreen) /
                        DisplayWidth(ourdisplay, ourscreen);
        pheight = (double)DisplayHeightMM(ourdisplay, ourscreen) /
                        DisplayHeight(ourdisplay, ourscreen);
        copystruct(&odev.v, &stdview);
        odev.v.type = VT_PER;
                                        /* map the window */
        XMapWindow(ourdisplay, gwind);
        dev_input();                    /* sets size and view angles */
                                        /* allocate our leaf pile */
        if (!qtAllocLeaves(DisplayWidth(ourdisplay,ourscreen) *
                        DisplayHeight(ourdisplay,ourscreen) * 3 /
                        (qtMinNodesiz*qtMinNodesiz*2)))
                error(SYSTEM, "insufficient memory for value storage");
        odev.name = id;
        odev.ifd = ConnectionNumber(ourdisplay);
                                        /* initialize cone array */
        initcones();
}


dev_close()                     /* close our display and free resources */
{
        glXMakeCurrent(ourdisplay, None, NULL);
        glXDestroyContext(ourdisplay, gctx);
        XDestroyWindow(ourdisplay, gwind);
        gwind = 0;
        XCloseDisplay(ourdisplay);
        ourdisplay = NULL;
        qtFreeLeaves();
        tmDone(NULL);
        freecones();
        odev.v.type = 0;
        odev.hres = odev.vres = 0;
        odev.ifd = -1;
}


int
dev_view(nv)                    /* assign new driver view */
register VIEW   *nv;
{
        if (nv->type == VT_PAR ||               /* check view legality */
                        nv->horiz > 160. || nv->vert > 160.) {
                error(COMMAND, "illegal view type/angle");
                nv->type = odev.v.type;
                nv->horiz = odev.v.horiz;
                nv->vert = odev.v.vert;
                return(0);
        }
        if (nv->vfore > FTINY) {
                error(COMMAND, "cannot handle fore clipping");
                nv->vfore = 0.;
                return(0);
        }
        if (nv != &odev.v) {
                if (!FEQ(nv->horiz,odev.v.horiz) ||     /* resize window? */
                                !FEQ(nv->vert,odev.v.vert)) {
                        int     dw = DisplayWidth(ourdisplay,ourscreen);
                        int     dh = DisplayHeight(ourdisplay,ourscreen);

                        dw -= 25;       /* for window frame */
                        dh -= 50;
                        odev.hres = 2.*VIEWDIST/pwidth *
                                        tan(PI/180./2.*nv->horiz);
                        odev.vres = 2.*VIEWDIST/pheight *
                                        tan(PI/180./2.*nv->vert);
                        if (odev.hres > dw) {
                                odev.vres = dw * odev.vres / odev.hres;
                                odev.hres = dw;
                        }
                        if (odev.vres > dh) {
                                odev.hres = dh * odev.hres / odev.vres;
                                odev.vres = dh;
                        }
                        XResizeWindow(ourdisplay, gwind, odev.hres, odev.vres);
                        dev_input();    /* get resize event */
                }
                copystruct(&odev.v, nv);
        }
        if (nxtzmax > FTINY) {
                curzmax = nxtzmax;
                nxtzmax = 0.;
        }
        glClear(GL_DEPTH_BUFFER_BIT);
        qtReplant();
        return(1);
}


int
dev_input()                     /* get X11 input */
{
        inpresflags = 0;

        do
                getevent();

        while (XQLength(ourdisplay) > 0);

        return(inpresflags);
}


int
dev_flush()                     /* flush output */
{
        qtUpdate();
        glFlush();
        rayqleft = RAYQLEN;
        return(XPending(ourdisplay));
}


dev_cone(rgb, ip, rad)          /* render a cone in view coordinates */
BYTE    rgb[3];
FVECT   ip;
double  rad;
{
        register int    ci, j;
        double  apexh, basez;
                                        /* is window mapped? */
        if (!mapped)
                return;
                                        /* compute apex height (0. to 1.) */
        if (ip[2] > 1e6)
                apexh = 1. - 1./DEPTHFACT;
        else {
                if (ip[2] > nxtzmax)
                        nxtzmax = ip[2];
                if (ip[2] >= curzmax)
                        apexh = 1. - 1./DEPTHFACT;
                else
                        apexh = 1. - ip[2]/(curzmax*DEPTHFACT);
        }
        rad *= 1.25;                    /* find conservative cone match */
        for (ci = 0; ci < MAXCONE-1; ci++)
                if (cone[ci].rad >= rad)
                        break;
                                        /* draw it */
        glColor3ub(rgb[0], rgb[1], rgb[2]);
        glBegin(GL_TRIANGLE_FAN);
        glVertex3d(ip[0], ip[1], apexh);        /* start with apex */
        basez = apexh*cone[ci].va[0][2];        /* base z's all the same */
        for (j = 0; j < cone[ci].nverts; j++)   /* draw each face */
                glVertex3d(ip[0]+cone[ci].va[j][0], ip[1]+cone[ci].va[j][1],
                                basez);
                                                /* connect last to first */
        glVertex3d(ip[0]+cone[ci].va[0][0], ip[1]+cone[ci].va[0][1], basez);
        glEnd();                                /* all done */
}


static int
mytmflags()                     /* figure out tone mapping flags */
{
        extern char     *progname;
        register char   *cp, *tail;
                                        /* find basic name */
        for (cp = tail = progname; *cp; cp++)
                if (*cp == '/')
                        tail = cp+1;
        for (cp = tail; *cp && *cp != '.'; cp++)
                ;
        if (cp-tail == 3 && !strncmp(tail, "glx", 3))
                return(TM_F_CAMERA|TM_F_NOSTDERR);
        if (cp-tail == 4 && !strncmp(tail, "glxh", 4))
                return(TM_F_HUMAN|TM_F_NOSTDERR);
        error(USER, "illegal driver name");
}


static
initcones()                     /* initialize cone vertices */
{
        register int    i, j;
        double  minrad, d;

        if (cone[0].nverts)
                freecones();
        minrad = 2.*qtMinNodesiz/(double)(DisplayWidth(ourdisplay,ourscreen) +
                                        DisplayHeight(ourdisplay,ourscreen));
        for (i = 0; i < MAXCONE; i++) {
                d = (double)i/(MAXCONE-1); d *= d;      /* x^2 distribution */
                cone[i].rad = minrad + (1.-minrad)*d;
                cone[i].nverts = MINVERT + (MAXVERT-MINVERT)*d;
                cone[i].va = (FVECT *)malloc(cone[i].nverts*sizeof(FVECT));
                if (cone[i].va == NULL)
                        error(SYSTEM, "out of memory in initcones");
                for (j = cone[i].nverts; j--; ) {
                        d = 2.*PI * (j+.5) / (cone[i].nverts);
                        cone[i].va[j][0] = cos(d) * cone[i].rad;
                        cone[i].va[j][1] = sin(d) * cone[i].rad;
                        cone[i].va[j][2] = 1. - cone[i].rad;
                }
        }
}


static
freecones()                     /* free cone vertices */
{
        register int    i;

        for (i = MAXCONE; i--; )
                if (cone[i].nverts) {
                        free((char *)cone[i].va);
                        cone[i].va = NULL;
                        cone[i].nverts = 0;
                }
}


static
getevent()                      /* get next event */
{
        XNextEvent(ourdisplay, levptr(XEvent));
        switch (levptr(XEvent)->type) {
        case ConfigureNotify:
                resizewindow(levptr(XConfigureEvent));
                break;
        case UnmapNotify:
                mapped = 0;
                break;
        case MapNotify:
                mapped = 1;
                break;
        case Expose:
                fixwindow(levptr(XExposeEvent));
                break;
        case KeyPress:
                getkey(levptr(XKeyPressedEvent));
                break;
        case ButtonPress:
                getmove(levptr(XButtonPressedEvent));
                break;
        }
}


static
draw3dline(wp)                  /* draw 3d line in world coordinates */
register FVECT  wp[2];
{
        glVertex3d(wp[0][0], wp[0][1], wp[0][2]);
        glVertex3d(wp[1][0], wp[1][1], wp[1][2]);
}


static
draw_grids()                    /* draw holodeck section grids */
{
        static BYTE     gridrgba[4] = {0x0, 0xff, 0xff, 0x00};
        double  xmin, xmax, ymin, ymax, zmin, zmax;
        double  d, cx, sx, crad;
        FVECT   vx, vy;
        register int    i, j;
                                        /* can we even do it? */
        if (!mapped || odev.v.type != VT_PER)
                return;
                                        /* compute view frustum */
        if (normalize(odev.v.vdir) == 0.0)
                return;
        zmin = 0.01;
        zmax = 10000.;
        if (odev.v.vfore > FTINY)
                zmin = odev.v.vfore;
        if (odev.v.vaft > FTINY)
                zmax = odev.v.vaft;
        xmax = zmin * tan(PI/180./2. * odev.v.horiz);
        xmin = -xmax;
        d = odev.v.hoff * (xmax - xmin);
        xmin += d; xmax += d;
        ymax = zmin * tan(PI/180./2. * odev.v.vert);
        ymin = -ymax;
        d = odev.v.voff * (ymax - ymin);
        ymin += d; ymax += d;
                                        /* set view matrix */
        glMatrixMode(GL_PROJECTION);
        glPushMatrix();
        glLoadIdentity();
        glFrustum(xmin, xmax, ymin, ymax, zmin, zmax);
        gluLookAt(odev.v.vp[0], odev.v.vp[1], odev.v.vp[2],
                odev.v.vp[0] + odev.v.vdir[0],
                odev.v.vp[1] + odev.v.vdir[1],
                odev.v.vp[2] + odev.v.vdir[2],
                odev.v.vup[0], odev.v.vup[1], odev.v.vup[2]);
        glDisable(GL_DEPTH_TEST);       /* write no depth values */
        glColor4ub(gridrgba[0], gridrgba[1], gridrgba[2], gridrgba[3]);
        glBegin(GL_LINES);              /* draw each grid line */
        gridlines(draw3dline);
        glEnd();
        glEnable(GL_DEPTH_TEST);        /* restore rendering params */
        glPopMatrix();
}


static
moveview(dx, dy, mov, orb)      /* move our view */
int     dx, dy, mov, orb;
{
        VIEW    nv;
        FVECT   odir, v1;
        double  d;
        register int    li;
                                /* start with old view */
        copystruct(&nv, &odev.v);
                                /* change view direction */
        if (mov | orb) {
                if ((li = qtFindLeaf(dx, dy)) < 0)
                        return(0);      /* not on window */
                VSUM(odir, qtL.wp[li], nv.vp, -1.);
        } else {
                if (viewray(nv.vp, nv.vdir, &odev.v,
                                (dx+.5)/odev.hres, (dy+.5)/odev.vres) < -FTINY)
                        return(0);      /* outside view */
        }
        if (orb && mov) {               /* orbit left/right */
                spinvector(odir, odir, nv.vup, d=MOVDEG*PI/180.*mov);
                VSUM(nv.vp, qtL.wp[li], odir, -1.);
                spinvector(nv.vdir, nv.vdir, nv.vup, d);
        } else if (orb) {               /* orbit up/down */
                fcross(v1, odir, nv.vup);
                if (normalize(v1) == 0.)
                        return(0);
                spinvector(odir, odir, v1, d=MOVDEG*PI/180.*orb);
                VSUM(nv.vp, qtL.wp[li], odir, -1.);
                spinvector(nv.vdir, nv.vdir, v1, d);
        } else if (mov) {               /* move forward/backward */
                d = MOVPCT/100. * mov;
                VSUM(nv.vp, nv.vp, odir, d);
        }
        if (!mov ^ !orb && headlocked) {        /* restore head height */
                VSUM(v1, odev.v.vp, nv.vp, -1.);
                d = DOT(v1, odev.v.vup);
                VSUM(nv.vp, nv.vp, odev.v.vup, d);
        }
        if (setview(&nv) != NULL)
                return(0);      /* illegal view */
        dev_view(&nv);
        inpresflags |= DFL(DC_SETVIEW);
        return(1);
}


static
getmove(ebut)                           /* get view change */
XButtonPressedEvent     *ebut;
{
        int     movdir = MOVDIR(ebut->button);
        int     movorb = MOVORB(ebut->state);
        int     oldnodesiz = qtMinNodesiz;
        Window  rootw, childw;
        int     rootx, rooty, wx, wy;
        unsigned int    statemask;

        qtMinNodesiz = 24;              /* accelerate update rate */
        XNoOp(ourdisplay);

        while (!XCheckMaskEvent(ourdisplay,
                        ButtonReleaseMask, levptr(XEvent))) {

                if (!XQueryPointer(ourdisplay, gwind, &rootw, &childw,
                                &rootx, &rooty, &wx, &wy, &statemask))
                        break;          /* on another screen */

                if (!moveview(wx, odev.vres-1-wy, movdir, movorb)) {
                        sleep(1);
                        continue;
                }
                glClear(GL_COLOR_BUFFER_BIT);
                qtUpdate();
                draw_grids();
                glFlush();
        }
        if (!(inpresflags & DFL(DC_SETVIEW))) { /* do final motion */
                movdir = MOVDIR(levptr(XButtonReleasedEvent)->button);
                wx = levptr(XButtonReleasedEvent)->x;
                wy = levptr(XButtonReleasedEvent)->y;
                moveview(wx, odev.vres-1-wy, movdir, movorb);
        }
        dev_flush();

        qtMinNodesiz = oldnodesiz;      /* restore quadtree resolution */
}


static
getkey(ekey)                            /* get input key */
register XKeyPressedEvent  *ekey;
{
        int  n;
        char    buf[8];

        n = XLookupString(ekey, buf, sizeof(buf), NULL, NULL);
        if (n != 1)
                return;
        switch (buf[0]) {
        case 'h':                       /* turn on height motion lock */
                headlocked = 1;
                return;
        case 'H':                       /* turn off height motion lock */
                headlocked = 0;
                return;
        case 'l':                       /* retrieve last view */
                inpresflags |= DFL(DC_LASTVIEW);
                return;
        case 'p':                       /* pause computation */
                inpresflags |= DFL(DC_PAUSE);
                return;
        case 'v':                       /* spit out view */
                inpresflags |= DFL(DC_GETVIEW);
                return;
        case '\n':
        case '\r':                      /* resume computation */
                inpresflags |= DFL(DC_RESUME);
                return;
        case CTRL('R'):                 /* redraw screen */
                if (nxtzmax > FTINY) {
                        curzmax = nxtzmax;
                        nxtzmax = 0.;
                }
                glClear(GL_DEPTH_BUFFER_BIT);
                qtRedraw(0, 0, odev.hres, odev.vres);
                return;
        case CTRL('L'):                 /* refresh from server */
                if (inpresflags & DFL(DC_REDRAW))
                        return;
                if (nxtzmax > FTINY) {
                        curzmax = nxtzmax;
                        nxtzmax = 0.;
                }
                glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
                draw_grids();
                glFlush();
                qtCompost(100);                 /* get rid of old values */
                inpresflags |= DFL(DC_REDRAW);  /* resend values from server */
                rayqleft = 0;                   /* hold off update */
                return;
        case 'K':                       /* kill rtrace process(es) */
                inpresflags |= DFL(DC_KILL);
                break;
        case 'R':                       /* restart rtrace */
                inpresflags |= DFL(DC_RESTART);
                break;
        case 'C':                       /* clobber holodeck */
                inpresflags |= DFL(DC_CLOBBER);
                break;
        case 'q':                       /* quit the program */
                inpresflags |= DFL(DC_QUIT);
                return;
        default:
                XBell(ourdisplay, 0);
                return;
        }
}


static
fixwindow(eexp)                         /* repair damage to window */
register XExposeEvent  *eexp;
{
        int     xmin, xmax, ymin, ymax;

        if (odev.hres == 0 || odev.vres == 0)   /* first exposure */
                resizewindow((XConfigureEvent *)eexp);
        xmin = eexp->x; xmax = eexp->x + eexp->width;
        ymin = odev.vres - eexp->y - eexp->height; ymax = odev.vres - eexp->y;
                                                /* clear portion of depth */
        glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
        glDepthFunc(GL_ALWAYS);
        glBegin(GL_POLYGON);
        glVertex3d((double)xmin/odev.hres, (double)ymin/odev.vres, 0.);
        glVertex3d((double)xmax/odev.hres, (double)ymin/odev.vres, 0.);
        glVertex3d((double)xmax/odev.hres, (double)ymax/odev.vres, 0.);
        glVertex3d((double)xmin/odev.hres, (double)ymax/odev.vres, 0.);
        glEnd();
        glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
        glDepthFunc(GL_LEQUAL);
        qtRedraw(xmin, ymin, xmax, ymax);
}


static
resizewindow(ersz)                      /* resize window */
register XConfigureEvent  *ersz;
{
        glViewport(0, 0, ersz->width, ersz->height);

        if (ersz->width == odev.hres && ersz->height == odev.vres)
                return;

        odev.hres = ersz->width;
        odev.vres = ersz->height;

        odev.v.horiz = 2.*180./PI * atan(0.5/VIEWDIST*pwidth*odev.hres);
        odev.v.vert = 2.*180./PI * atan(0.5/VIEWDIST*pheight*odev.vres);

        inpresflags |= DFL(DC_SETVIEW);
}
Revision:	3.13
Committed:	Sun Jan 4 08:32:00 1998 UTC (26 years, 3 months ago) by gregl
Content type:	text/plain
Branch:	MAIN
Changes since 3.12:	+1 -0 lines
Log Message:	delay update after ^L
#	User	Rev	Content
1	gregl	3.1	/* Copyright (c) 1997 Silicon Graphics, Inc. */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ SGI";
5			#endif
6
7			/*
8			* OpenGL GLX driver for holodeck display.
9	gregl	3.2	* Based on x11 driver.
10	gregl	3.1	*/
11
12			#include "standard.h"
13	gregl	3.4	#include "rhd_qtree.h"
14	gregl	3.1
15			#include <GL/glx.h>
16
17			#include "x11icon.h"
18
19	gregl	3.10	#ifndef RAYQLEN
20			#define RAYQLEN 50000 /* max. rays to queue before flush */
21			#endif
22
23	gregl	3.1	#ifndef FEQ
24			#define FEQ(a,b) ((a)-(b) <= FTINY && (a)-(b) >= -FTINY)
25			#endif
26
27	gregl	3.4	#ifndef MAXCONE
28			#define MAXCONE 16 /* number of different cone sizes */
29	gregl	3.1	#endif
30	gregl	3.4	#ifndef MAXVERT
31			#define MAXVERT 32 /* maximum number of cone vertices */
32	gregl	3.1	#endif
33	gregl	3.4	#ifndef MINVERT
34			#define MINVERT 4 /* minimum number of cone vertices */
35	gregl	3.1	#endif
36	gregl	3.4	#ifndef DEPTHFACT
37			#define DEPTHFACT 16. /* multiplier for depth tests */
38	gregl	3.1	#endif
39
40	gregl	3.2	#define GAMMA 1.4 /* default gamma correction */
41	gregl	3.1
42			#define MOVPCT 7 /* percent distance to move /frame */
43			#define MOVDIR(b) ((b)==Button1 ? 1 : (b)==Button2 ? 0 : -1)
44			#define MOVDEG (-5) /* degrees to orbit CW/down /frame */
45			#define MOVORB(s) ((s)&ShiftMask ? 1 : (s)&ControlMask ? -1 : 0)
46
47			#define MINWIDTH 480 /* minimum graphics window width */
48			#define MINHEIGHT 400 /* minimum graphics window height */
49
50			#define VIEWDIST 356 /* assumed viewing distance (mm) */
51
52			#define BORWIDTH 5 /* border width */
53
54			#define ourscreen DefaultScreen(ourdisplay)
55			#define ourroot RootWindow(ourdisplay,ourscreen)
56			#define ourmask (StructureNotifyMask\|ExposureMask\|KeyPressMask\|\
57			ButtonPressMask\|ButtonReleaseMask)
58
59			#define levptr(etype) ((etype *)&currentevent)
60
61			struct driver odev; /* global device driver structure */
62
63			static XEvent currentevent; /* current event */
64
65			static int mapped = 0; /* window is mapped? */
66			static unsigned long ourblack=0, ourwhite=~0;
67
68			static Display ourdisplay = NULL; / our display */
69			static XVisualInfo ourvinf; / our visual information */
70			static Window gwind = 0; /* our graphics window */
71			static GLXContext gctx; /* our GLX context */
72
73			static double pwidth, pheight; /* pixel dimensions (mm) */
74
75	gregl	3.4	static double curzmax = 1e4; /* current depth upper limit */
76			static double nxtzmax = 0.; /* maximum (finite) depth so far */
77	gregl	3.1
78	gregl	3.4	static struct {
79			double rad; /* cone radius */
80			int nverts; /* number of vertices */
81			FVECT va; / allocated vertex array */
82			} cone[MAXCONE]; /* precomputed cones for drawing */
83
84	gregl	3.1	static int inpresflags; /* input result flags */
85
86			static int headlocked = 0; /* lock vertical motion */
87
88			static int resizewindow(), getevent(), getkey(), moveview(),
89	gregl	3.4	initcones(), freecones(),
90			getmove(), fixwindow(), mytmflags();
91	gregl	3.1
92
93			dev_open(id) /* initialize X11 driver */
94			char *id;
95			{
96			extern char *getenv();
97			static int atlBest[] = {GLX_RGBA, GLX_RED_SIZE,8,
98			GLX_GREEN_SIZE,8, GLX_BLUE_SIZE,8,
99	gregl	3.4	GLX_DEPTH_SIZE,15, None};
100	gregl	3.1	char *gv;
101			double gamval = GAMMA;
102			XSetWindowAttributes ourwinattr;
103			XWMHints ourxwmhints;
104			XSizeHints oursizhints;
105	gregl	3.4	/* set quadtree globals */
106			qtMinNodesiz = 3;
107	gregl	3.9	qtDepthEps = 0.07;
108	gregl	3.1	/* open display server */
109			ourdisplay = XOpenDisplay(NULL);
110			if (ourdisplay == NULL)
111			error(USER, "cannot open X-windows; DISPLAY variable set?\n");
112			/* find a usable visual */
113			ourvinf = glXChooseVisual(ourdisplay, ourscreen, atlBest);
114			if (ourvinf == NULL)
115			error(USER, "no suitable visuals available");
116			/* get a context */
117			gctx = glXCreateContext(ourdisplay, ourvinf, NULL, GL_TRUE);
118			/* set gamma and tone mapping */
119			if ((gv = XGetDefault(ourdisplay, "radiance", "gamma")) != NULL
120			\|\| (gv = getenv("DISPLAY_GAMMA")) != NULL)
121			gamval = atof(gv);
122			if (tmInit(mytmflags(), stdprims, gamval) == NULL)
123			error(SYSTEM, "not enough memory in dev_open");
124			/* open window */
125			ourwinattr.background_pixel = ourblack;
126			ourwinattr.border_pixel = ourblack;
127			ourwinattr.event_mask = ourmask;
128			/* this is stupid */
129			ourwinattr.colormap = XCreateColormap(ourdisplay, ourroot,
130			ourvinf->visual, AllocNone);
131			gwind = XCreateWindow(ourdisplay, ourroot, 0, 0,
132			DisplayWidth(ourdisplay,ourscreen)-2*BORWIDTH,
133			DisplayHeight(ourdisplay,ourscreen)-2*BORWIDTH,
134			BORWIDTH, ourvinf->depth, InputOutput, ourvinf->visual,
135			CWBackPixel\|CWBorderPixel\|CWColormap\|CWEventMask, &ourwinattr);
136			if (gwind == 0)
137			error(SYSTEM, "cannot create window\n");
138			XStoreName(ourdisplay, gwind, id);
139			/* set window manager hints */
140			ourxwmhints.flags = InputHint\|IconPixmapHint;
141			ourxwmhints.input = True;
142			ourxwmhints.icon_pixmap = XCreateBitmapFromData(ourdisplay,
143			gwind, x11icon_bits, x11icon_width, x11icon_height);
144			XSetWMHints(ourdisplay, gwind, &ourxwmhints);
145			oursizhints.min_width = MINWIDTH;
146			oursizhints.min_height = MINHEIGHT;
147			oursizhints.flags = PMinSize;
148			XSetNormalHints(ourdisplay, gwind, &oursizhints);
149	gregl	3.2	/* set GLX context */
150			glXMakeCurrent(ourdisplay, gwind, gctx);
151			glEnable(GL_DEPTH_TEST);
152			glDepthFunc(GL_LEQUAL);
153			glShadeModel(GL_FLAT);
154			glDisable(GL_DITHER);
155	gregl	3.4	glDisable(GL_CULL_FACE);
156			glMatrixMode(GL_PROJECTION);
157			glOrtho(0., 1., 0., 1., -.01, 1.01);
158			glTranslated(0., 0., -1.01);
159	gregl	3.1	/* figure out sensible view */
160			pwidth = (double)DisplayWidthMM(ourdisplay, ourscreen) /
161			DisplayWidth(ourdisplay, ourscreen);
162			pheight = (double)DisplayHeightMM(ourdisplay, ourscreen) /
163			DisplayHeight(ourdisplay, ourscreen);
164			copystruct(&odev.v, &stdview);
165			odev.v.type = VT_PER;
166	gregl	3.2	/* map the window */
167			XMapWindow(ourdisplay, gwind);
168			dev_input(); /* sets size and view angles */
169	gregl	3.4	/* allocate our leaf pile */
170	gregl	3.9	if (!qtAllocLeaves(DisplayWidth(ourdisplay,ourscreen) *
171	gregl	3.11	DisplayHeight(ourdisplay,ourscreen) * 3 /
172			(qtMinNodesizqtMinNodesiz2)))
173	gregl	3.2	error(SYSTEM, "insufficient memory for value storage");
174	gregl	3.1	odev.name = id;
175			odev.ifd = ConnectionNumber(ourdisplay);
176	gregl	3.4	/* initialize cone array */
177			initcones();
178	gregl	3.1	}
179
180
181			dev_close() /* close our display and free resources */
182			{
183			glXMakeCurrent(ourdisplay, None, NULL);
184			glXDestroyContext(ourdisplay, gctx);
185			XDestroyWindow(ourdisplay, gwind);
186			gwind = 0;
187			XCloseDisplay(ourdisplay);
188			ourdisplay = NULL;
189	gregl	3.4	qtFreeLeaves();
190	gregl	3.1	tmDone(NULL);
191	gregl	3.4	freecones();
192	gregl	3.1	odev.v.type = 0;
193			odev.hres = odev.vres = 0;
194			odev.ifd = -1;
195			}
196
197
198			int
199			dev_view(nv) /* assign new driver view */
200			register VIEW *nv;
201			{
202	gregl	3.4	if (nv->type == VT_PAR \|\| /* check view legality */
203			nv->horiz > 160. \|\| nv->vert > 160.) {
204	gregl	3.1	error(COMMAND, "illegal view type/angle");
205	gregl	3.4	nv->type = odev.v.type;
206	gregl	3.1	nv->horiz = odev.v.horiz;
207			nv->vert = odev.v.vert;
208			return(0);
209			}
210	gregl	3.4	if (nv->vfore > FTINY) {
211			error(COMMAND, "cannot handle fore clipping");
212			nv->vfore = 0.;
213			return(0);
214			}
215	gregl	3.1	if (nv != &odev.v) {
216			if (!FEQ(nv->horiz,odev.v.horiz) \|\| /* resize window? */
217			!FEQ(nv->vert,odev.v.vert)) {
218			int dw = DisplayWidth(ourdisplay,ourscreen);
219			int dh = DisplayHeight(ourdisplay,ourscreen);
220
221			dw -= 25; /* for window frame */
222			dh -= 50;
223			odev.hres = 2.VIEWDIST/pwidth
224			tan(PI/180./2.*nv->horiz);
225			odev.vres = 2.VIEWDIST/pheight
226			tan(PI/180./2.*nv->vert);
227			if (odev.hres > dw) {
228			odev.vres = dw * odev.vres / odev.hres;
229			odev.hres = dw;
230			}
231			if (odev.vres > dh) {
232			odev.hres = dh * odev.hres / odev.vres;
233			odev.vres = dh;
234			}
235			XResizeWindow(ourdisplay, gwind, odev.hres, odev.vres);
236	gregl	3.2	dev_input(); /* get resize event */
237	gregl	3.1	}
238			copystruct(&odev.v, nv);
239			}
240	gregl	3.4	if (nxtzmax > FTINY) {
241			curzmax = nxtzmax;
242			nxtzmax = 0.;
243			}
244			glClear(GL_DEPTH_BUFFER_BIT);
245			qtReplant();
246	gregl	3.1	return(1);
247			}
248
249
250			int
251			dev_input() /* get X11 input */
252			{
253			inpresflags = 0;
254
255			do
256			getevent();
257
258			while (XQLength(ourdisplay) > 0);
259
260			return(inpresflags);
261			}
262
263
264	gregl	3.4	int
265			dev_flush() /* flush output */
266	gregl	3.1	{
267	gregl	3.4	qtUpdate();
268			glFlush();
269	gregl	3.10	rayqleft = RAYQLEN;
270	gregl	3.4	return(XPending(ourdisplay));
271	gregl	3.1	}
272
273
274	gregl	3.4	dev_cone(rgb, ip, rad) /* render a cone in view coordinates */
275			BYTE rgb[3];
276			FVECT ip;
277			double rad;
278	gregl	3.1	{
279	gregl	3.4	register int ci, j;
280			double apexh, basez;
281	gregl	3.12	/* is window mapped? */
282			if (!mapped)
283			return;
284	gregl	3.4	/* compute apex height (0. to 1.) */
285			if (ip[2] > 1e6)
286			apexh = 1. - 1./DEPTHFACT;
287			else {
288			if (ip[2] > nxtzmax)
289			nxtzmax = ip[2];
290			if (ip[2] >= curzmax)
291			apexh = 1. - 1./DEPTHFACT;
292			else
293			apexh = 1. - ip[2]/(curzmax*DEPTHFACT);
294	gregl	3.1	}
295	gregl	3.5	rad = 1.25; / find conservative cone match */
296	gregl	3.4	for (ci = 0; ci < MAXCONE-1; ci++)
297			if (cone[ci].rad >= rad)
298			break;
299			/* draw it */
300			glColor3ub(rgb[0], rgb[1], rgb[2]);
301			glBegin(GL_TRIANGLE_FAN);
302			glVertex3d(ip[0], ip[1], apexh); /* start with apex */
303			basez = apexhcone[ci].va[0][2]; / base z's all the same */
304			for (j = 0; j < cone[ci].nverts; j++) /* draw each face */
305			glVertex3d(ip[0]+cone[ci].va[j][0], ip[1]+cone[ci].va[j][1],
306			basez);
307			/* connect last to first */
308			glVertex3d(ip[0]+cone[ci].va[0][0], ip[1]+cone[ci].va[0][1], basez);
309			glEnd(); /* all done */
310	gregl	3.1	}
311
312
313			static int
314			mytmflags() /* figure out tone mapping flags */
315			{
316			extern char *progname;
317			register char cp, tail;
318			/* find basic name */
319			for (cp = tail = progname; *cp; cp++)
320			if (*cp == '/')
321			tail = cp+1;
322			for (cp = tail; cp && cp != '.'; cp++)
323			;
324			if (cp-tail == 3 && !strncmp(tail, "glx", 3))
325	gregl	3.10	return(TM_F_CAMERA\|TM_F_NOSTDERR);
326	gregl	3.1	if (cp-tail == 4 && !strncmp(tail, "glxh", 4))
327	gregl	3.10	return(TM_F_HUMAN\|TM_F_NOSTDERR);
328	gregl	3.1	error(USER, "illegal driver name");
329			}
330
331
332			static
333	gregl	3.4	initcones() /* initialize cone vertices */
334	gregl	3.1	{
335			register int i, j;
336	gregl	3.4	double minrad, d;
337	gregl	3.1
338	gregl	3.4	if (cone[0].nverts)
339			freecones();
340			minrad = 2.*qtMinNodesiz/(double)(DisplayWidth(ourdisplay,ourscreen) +
341			DisplayHeight(ourdisplay,ourscreen));
342			for (i = 0; i < MAXCONE; i++) {
343			d = (double)i/(MAXCONE-1); d = d; / x^2 distribution */
344			cone[i].rad = minrad + (1.-minrad)*d;
345			cone[i].nverts = MINVERT + (MAXVERT-MINVERT)*d;
346			cone[i].va = (FVECT )malloc(cone[i].nvertssizeof(FVECT));
347			if (cone[i].va == NULL)
348			error(SYSTEM, "out of memory in initcones");
349			for (j = cone[i].nverts; j--; ) {
350			d = 2.PI (j+.5) / (cone[i].nverts);
351			cone[i].va[j][0] = cos(d) * cone[i].rad;
352			cone[i].va[j][1] = sin(d) * cone[i].rad;
353			cone[i].va[j][2] = 1. - cone[i].rad;
354	gregl	3.2	}
355			}
356			}
357
358
359			static
360	gregl	3.4	freecones() /* free cone vertices */
361	gregl	3.2	{
362	gregl	3.4	register int i;
363	gregl	3.2
364	gregl	3.4	for (i = MAXCONE; i--; )
365			if (cone[i].nverts) {
366			free((char *)cone[i].va);
367			cone[i].va = NULL;
368			cone[i].nverts = 0;
369	gregl	3.2	}
370			}
371
372
373			static
374	gregl	3.1	getevent() /* get next event */
375			{
376			XNextEvent(ourdisplay, levptr(XEvent));
377			switch (levptr(XEvent)->type) {
378			case ConfigureNotify:
379			resizewindow(levptr(XConfigureEvent));
380			break;
381			case UnmapNotify:
382			mapped = 0;
383			break;
384			case MapNotify:
385			mapped = 1;
386			break;
387			case Expose:
388			fixwindow(levptr(XExposeEvent));
389			break;
390			case KeyPress:
391			getkey(levptr(XKeyPressedEvent));
392			break;
393			case ButtonPress:
394			getmove(levptr(XButtonPressedEvent));
395			break;
396			}
397			}
398
399
400			static
401			draw3dline(wp) /* draw 3d line in world coordinates */
402			register FVECT wp[2];
403			{
404			glVertex3d(wp[0][0], wp[0][1], wp[0][2]);
405			glVertex3d(wp[1][0], wp[1][1], wp[1][2]);
406			}
407
408
409			static
410			draw_grids() /* draw holodeck section grids */
411			{
412	gregl	3.2	static BYTE gridrgba[4] = {0x0, 0xff, 0xff, 0x00};
413	gregl	3.4	double xmin, xmax, ymin, ymax, zmin, zmax;
414			double d, cx, sx, crad;
415			FVECT vx, vy;
416			register int i, j;
417			/* can we even do it? */
418			if (!mapped \|\| odev.v.type != VT_PER)
419	gregl	3.1	return;
420	gregl	3.4	/* compute view frustum */
421			if (normalize(odev.v.vdir) == 0.0)
422			return;
423			zmin = 0.01;
424			zmax = 10000.;
425			if (odev.v.vfore > FTINY)
426			zmin = odev.v.vfore;
427			if (odev.v.vaft > FTINY)
428			zmax = odev.v.vaft;
429			xmax = zmin * tan(PI/180./2. * odev.v.horiz);
430			xmin = -xmax;
431			d = odev.v.hoff * (xmax - xmin);
432			xmin += d; xmax += d;
433			ymax = zmin * tan(PI/180./2. * odev.v.vert);
434			ymin = -ymax;
435			d = odev.v.voff * (ymax - ymin);
436			ymin += d; ymax += d;
437			/* set view matrix */
438			glMatrixMode(GL_PROJECTION);
439			glPushMatrix();
440			glLoadIdentity();
441			glFrustum(xmin, xmax, ymin, ymax, zmin, zmax);
442			gluLookAt(odev.v.vp[0], odev.v.vp[1], odev.v.vp[2],
443			odev.v.vp[0] + odev.v.vdir[0],
444			odev.v.vp[1] + odev.v.vdir[1],
445			odev.v.vp[2] + odev.v.vdir[2],
446			odev.v.vup[0], odev.v.vup[1], odev.v.vup[2]);
447			glDisable(GL_DEPTH_TEST); /* write no depth values */
448	gregl	3.1	glColor4ub(gridrgba[0], gridrgba[1], gridrgba[2], gridrgba[3]);
449	gregl	3.4	glBegin(GL_LINES); /* draw each grid line */
450	gregl	3.1	gridlines(draw3dline);
451			glEnd();
452	gregl	3.4	glEnable(GL_DEPTH_TEST); /* restore rendering params */
453			glPopMatrix();
454	gregl	3.1	}
455
456
457			static
458			moveview(dx, dy, mov, orb) /* move our view */
459			int dx, dy, mov, orb;
460			{
461			VIEW nv;
462			FVECT odir, v1;
463			double d;
464			register int li;
465			/* start with old view */
466			copystruct(&nv, &odev.v);
467			/* change view direction */
468			if (mov \| orb) {
469	gregl	3.4	if ((li = qtFindLeaf(dx, dy)) < 0)
470	gregl	3.1	return(0); /* not on window */
471	gregl	3.4	VSUM(odir, qtL.wp[li], nv.vp, -1.);
472	gregl	3.1	} else {
473			if (viewray(nv.vp, nv.vdir, &odev.v,
474			(dx+.5)/odev.hres, (dy+.5)/odev.vres) < -FTINY)
475			return(0); /* outside view */
476			}
477			if (orb && mov) { /* orbit left/right */
478			spinvector(odir, odir, nv.vup, d=MOVDEGPI/180.mov);
479	gregl	3.4	VSUM(nv.vp, qtL.wp[li], odir, -1.);
480	gregl	3.1	spinvector(nv.vdir, nv.vdir, nv.vup, d);
481			} else if (orb) { /* orbit up/down */
482			fcross(v1, odir, nv.vup);
483			if (normalize(v1) == 0.)
484			return(0);
485			spinvector(odir, odir, v1, d=MOVDEGPI/180.orb);
486	gregl	3.4	VSUM(nv.vp, qtL.wp[li], odir, -1.);
487	gregl	3.1	spinvector(nv.vdir, nv.vdir, v1, d);
488			} else if (mov) { /* move forward/backward */
489			d = MOVPCT/100. * mov;
490			VSUM(nv.vp, nv.vp, odir, d);
491			}
492			if (!mov ^ !orb && headlocked) { /* restore head height */
493			VSUM(v1, odev.v.vp, nv.vp, -1.);
494			d = DOT(v1, odev.v.vup);
495			VSUM(nv.vp, nv.vp, odev.v.vup, d);
496			}
497			if (setview(&nv) != NULL)
498			return(0); /* illegal view */
499			dev_view(&nv);
500			inpresflags \|= DFL(DC_SETVIEW);
501			return(1);
502			}
503
504
505			static
506			getmove(ebut) /* get view change */
507			XButtonPressedEvent *ebut;
508			{
509			int movdir = MOVDIR(ebut->button);
510			int movorb = MOVORB(ebut->state);
511	gregl	3.4	int oldnodesiz = qtMinNodesiz;
512	gregl	3.1	Window rootw, childw;
513			int rootx, rooty, wx, wy;
514			unsigned int statemask;
515
516	gregl	3.4	qtMinNodesiz = 24; /* accelerate update rate */
517	gregl	3.1	XNoOp(ourdisplay);
518
519			while (!XCheckMaskEvent(ourdisplay,
520			ButtonReleaseMask, levptr(XEvent))) {
521
522			if (!XQueryPointer(ourdisplay, gwind, &rootw, &childw,
523			&rootx, &rooty, &wx, &wy, &statemask))
524			break; /* on another screen */
525
526			if (!moveview(wx, odev.vres-1-wy, movdir, movorb)) {
527			sleep(1);
528			continue;
529			}
530	gregl	3.4	glClear(GL_COLOR_BUFFER_BIT);
531			qtUpdate();
532	gregl	3.1	draw_grids();
533	gregl	3.4	glFlush();
534	gregl	3.1	}
535			if (!(inpresflags & DFL(DC_SETVIEW))) { /* do final motion */
536			movdir = MOVDIR(levptr(XButtonReleasedEvent)->button);
537			wx = levptr(XButtonReleasedEvent)->x;
538			wy = levptr(XButtonReleasedEvent)->y;
539			moveview(wx, odev.vres-1-wy, movdir, movorb);
540			}
541			dev_flush();
542	gregl	3.4
543			qtMinNodesiz = oldnodesiz; /* restore quadtree resolution */
544	gregl	3.1	}
545
546
547			static
548			getkey(ekey) /* get input key */
549			register XKeyPressedEvent *ekey;
550			{
551			int n;
552			char buf[8];
553
554			n = XLookupString(ekey, buf, sizeof(buf), NULL, NULL);
555			if (n != 1)
556			return;
557			switch (buf[0]) {
558			case 'h': /* turn on height motion lock */
559			headlocked = 1;
560			return;
561			case 'H': /* turn off height motion lock */
562			headlocked = 0;
563			return;
564			case 'l': /* retrieve last view */
565			inpresflags \|= DFL(DC_LASTVIEW);
566			return;
567			case 'p': /* pause computation */
568			inpresflags \|= DFL(DC_PAUSE);
569			return;
570			case 'v': /* spit out view */
571			inpresflags \|= DFL(DC_GETVIEW);
572			return;
573			case '\n':
574			case '\r': /* resume computation */
575			inpresflags \|= DFL(DC_RESUME);
576			return;
577			case CTRL('R'): /* redraw screen */
578	gregl	3.8	if (nxtzmax > FTINY) {
579			curzmax = nxtzmax;
580			nxtzmax = 0.;
581			}
582	gregl	3.2	glClear(GL_DEPTH_BUFFER_BIT);
583	gregl	3.4	qtRedraw(0, 0, odev.hres, odev.vres);
584	gregl	3.1	return;
585			case CTRL('L'): /* refresh from server */
586			if (inpresflags & DFL(DC_REDRAW))
587			return;
588	gregl	3.8	if (nxtzmax > FTINY) {
589			curzmax = nxtzmax;
590			nxtzmax = 0.;
591			}
592	gregl	3.1	glClear(GL_COLOR_BUFFER_BIT \| GL_DEPTH_BUFFER_BIT);
593			draw_grids();
594			glFlush();
595	gregl	3.4	qtCompost(100); /* get rid of old values */
596	gregl	3.1	inpresflags \|= DFL(DC_REDRAW); /* resend values from server */
597	gregl	3.13	rayqleft = 0; /* hold off update */
598	gregl	3.1	return;
599			case 'K': /* kill rtrace process(es) */
600			inpresflags \|= DFL(DC_KILL);
601			break;
602			case 'R': /* restart rtrace */
603			inpresflags \|= DFL(DC_RESTART);
604			break;
605			case 'C': /* clobber holodeck */
606			inpresflags \|= DFL(DC_CLOBBER);
607			break;
608			case 'q': /* quit the program */
609			inpresflags \|= DFL(DC_QUIT);
610			return;
611			default:
612			XBell(ourdisplay, 0);
613			return;
614			}
615			}
616
617
618			static
619			fixwindow(eexp) /* repair damage to window */
620			register XExposeEvent *eexp;
621			{
622	gregl	3.4	int xmin, xmax, ymin, ymax;
623
624	gregl	3.2	if (odev.hres == 0 \|\| odev.vres == 0) /* first exposure */
625			resizewindow((XConfigureEvent *)eexp);
626	gregl	3.4	xmin = eexp->x; xmax = eexp->x + eexp->width;
627			ymin = odev.vres - eexp->y - eexp->height; ymax = odev.vres - eexp->y;
628			/* clear portion of depth */
629			glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
630			glDepthFunc(GL_ALWAYS);
631			glBegin(GL_POLYGON);
632			glVertex3d((double)xmin/odev.hres, (double)ymin/odev.vres, 0.);
633			glVertex3d((double)xmax/odev.hres, (double)ymin/odev.vres, 0.);
634			glVertex3d((double)xmax/odev.hres, (double)ymax/odev.vres, 0.);
635			glVertex3d((double)xmin/odev.hres, (double)ymax/odev.vres, 0.);
636			glEnd();
637			glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
638			glDepthFunc(GL_LEQUAL);
639			qtRedraw(xmin, ymin, xmax, ymax);
640	gregl	3.1	}
641
642
643			static
644			resizewindow(ersz) /* resize window */
645			register XConfigureEvent *ersz;
646			{
647	gregl	3.6	glViewport(0, 0, ersz->width, ersz->height);
648
649	gregl	3.1	if (ersz->width == odev.hres && ersz->height == odev.vres)
650			return;
651
652			odev.hres = ersz->width;
653			odev.vres = ersz->height;
654
655			odev.v.horiz = 2.180./PI atan(0.5/VIEWDISTpwidthodev.hres);
656			odev.v.vert = 2.180./PI atan(0.5/VIEWDISTpheightodev.vres);
657
658			inpresflags \|= DFL(DC_SETVIEW);
659			}