src/hd/rhd_ogl.c

/* Copyright (c) 1998 Silicon Graphics, Inc. */

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

/*
 * OpenGL driver for holodeck display.
 * Based on GLX driver using T-mesh.
 *
 * Define symbol STEREO for stereo viewing.
 * Define symbol DOBJ for display object viewing.
 */

#ifdef NOSTEREO
#ifdef STEREO
#undef STEREO
#else
#undef NOSTEREO
#endif
#endif

#include "standard.h"

#include <sys/types.h>
#include <GL/glx.h>
#include <GL/glu.h>
#ifdef STEREO
#include <X11/extensions/SGIStereo.h>
#endif

#include "rhd_odraw.h"
#ifdef DOBJ
#include "rhdobj.h"
#endif

#include "x11icon.h"

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

#ifndef PORTALP
#define PORTRED         2               /* portal red color */
#define PORTGRN         -1              /* portal green left alone */
#define PORTBLU         128             /* portal blue color */
#define PORTALP         -1              /* don't use alpha channel */
#endif
#define isportal(c)     ((PORTRED<0 || (c)[0]==PORTRED) && \
                                (PORTGRN<0 || (c)[1]==PORTGRN) && \
                                (PORTBLU<0 || (c)[2]==PORTBLU) && \
                                (PORTALP<0 || (c)[3]==PORTALP))

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

#define GAMMA           1.4             /* default gamma correction */

#define FRAMESTATE(s)   (((s)&(ShiftMask|ControlMask))==(ShiftMask|ControlMask))

#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 setstereobuf(bid)       (glXWaitGL(), \
                                XSGISetStereoBuffer(ourdisplay, gwind, bid), \
                                glXWaitX())

#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 */

char odev_args[64];                     /* command arguments */

static GLfloat  *depthbuffer = NULL;    /* depth buffer */

#ifdef STEREO
static VIEW     vwright;                /* right eye view */
static GLfloat  *depthright = NULL;     /* right depth buffer */
#endif

static int      rayqleft = 0;           /* rays left to queue before flush */

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   dev_zmin, dev_zmax;     /* fore and aft clipping plane dist. */
static double   dev_zrat;               /* (1. - dev_zmin/dev_zmax) */

#define setzrat()       (dev_zrat = 1. - dev_zmin/dev_zmax)
#define mapdepth(d)     ((d)>0.9995 ? FHUGE : dev_zmin/(1.-(d)*dev_zrat))

static int      inpresflags;            /* input result flags */

static int      headlocked;             /* lock vertical motion */

static int      isperspective;          /* perspective/ortho view */

static int      viewsteady;             /* is view steady? */

static int  resizewindow(), getevent(), getkey(), moveview(), wipeclean(),
                xferdepth(), freedepth(), setglortho(),
                setglpersp(), getframe(), getmove(), fixwindow(), mytmflags();

static double   getdistance();

#ifdef STEREO
static int  pushright(), popright();
#endif

extern int      gmPortals;      /* GL portal list id */

extern time_t   time();


dev_open(id)                    /* initialize GLX driver */
char  *id;
{
        extern char     *getenv();
        static RGBPRIMS myprims = STDPRIMS;
#if (PORTALP<0)
        static int      atlBest[] = {GLX_RGBA, GLX_DOUBLEBUFFER,
                                GLX_RED_SIZE,8, GLX_GREEN_SIZE,8,
                                GLX_BLUE_SIZE,8, GLX_DEPTH_SIZE,15, None};
        static int      atlOK[] = {GLX_RGBA, GLX_DOUBLEBUFFER,
                                GLX_RED_SIZE,4, GLX_GREEN_SIZE,4,
                                GLX_BLUE_SIZE,4, GLX_DEPTH_SIZE,15, None};
#else
        static int      atlBest[] = {GLX_RGBA, GLX_DOUBLEBUFFER,
                                GLX_RED_SIZE,8, GLX_GREEN_SIZE,8,
                                GLX_BLUE_SIZE,8, GLX_ALPHA_SIZE,2,
                                GLX_DEPTH_SIZE,15, None};
        static int      atlOK[] = {GLX_RGBA, GLX_DOUBLEBUFFER,
                                GLX_RED_SIZE,4, GLX_GREEN_SIZE,4,
                                GLX_BLUE_SIZE,4, GLX_ALPHA_SIZE,2,
                                GLX_DEPTH_SIZE,15, None};
#endif
        char    *ev;
        double  gamval = GAMMA;
        RGBPRIMP        dpri = stdprims;
        XSetWindowAttributes    ourwinattr;
        XWMHints        ourxwmhints;
        XSizeHints      oursizhints;
                                        /* check for unsupported stereo */
#ifdef NOSTEREO
        error(INTERNAL, "stereo display driver unavailable");
#endif
                                        /* open display server */
        ourdisplay = XOpenDisplay(NULL);
        CHECK(ourdisplay==NULL, USER,
                        "cannot open X-windows; DISPLAY variable set?");
#ifdef STEREO
        switch (XSGIQueryStereoMode(ourdisplay, ourroot)) {
        case STEREO_TOP:
        case STEREO_BOTTOM:
                break;
        case STEREO_OFF:
                error(USER,
                "wrong video mode: run \"/usr/gfx/setmon -n STR_TOP\" first");
        case X_STEREO_UNSUPPORTED:
                error(USER, "stereo mode not supported on this screen");
        default:
                error(INTERNAL, "unknown stereo mode");
        }
#endif
                                        /* find a usable visual */
        ourvinf = glXChooseVisual(ourdisplay, ourscreen, atlBest);
        if (ourvinf == NULL)
                ourvinf = glXChooseVisual(ourdisplay, ourscreen, atlOK);
        CHECK(ourvinf==NULL, USER, "no suitable visuals available");
                                        /* get a context */
        gctx = glXCreateContext(ourdisplay, ourvinf, NULL, GL_TRUE);
                                        /* set gamma and tone mapping */
        if ((ev = XGetDefault(ourdisplay, "radiance", "gamma")) != NULL
                        || (ev = getenv("DISPLAY_GAMMA")) != NULL)
                gamval = atof(ev);
        if ((ev = getenv("DISPLAY_PRIMARIES")) != NULL &&
                        sscanf(ev, "%f %f %f %f %f %f %f %f",
                                &myprims[RED][CIEX],&myprims[RED][CIEY],
                                &myprims[GRN][CIEX],&myprims[GRN][CIEY],
                                &myprims[BLU][CIEX],&myprims[BLU][CIEY],
                                &myprims[WHT][CIEX],&myprims[WHT][CIEY]) >= 6)
                dpri = myprims;
        if (tmInit(mytmflags(), dpri, 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,
#ifdef STEREO
                (DisplayHeight(ourdisplay,ourscreen)-2*BORWIDTH)/2,
#else
                DisplayHeight(ourdisplay,ourscreen)-2*BORWIDTH,
#endif
                BORWIDTH, ourvinf->depth, InputOutput, ourvinf->visual,
                CWBackPixel|CWBorderPixel|CWColormap|CWEventMask, &ourwinattr);
        CHECK(gwind==0, SYSTEM, "cannot create window");
        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;
#ifdef STEREO
        oursizhints.min_height = MINHEIGHT/2;
        oursizhints.max_width = DisplayWidth(ourdisplay,ourscreen)-2*BORWIDTH;
        oursizhints.max_height = (DisplayHeight(ourdisplay,ourscreen) -
                                        2*BORWIDTH)/2;
        oursizhints.flags = PMinSize|PMaxSize;
#else
        oursizhints.min_height = MINHEIGHT;
        oursizhints.flags = PMinSize;
#endif
        XSetNormalHints(ourdisplay, gwind, &oursizhints);
                                        /* set GLX context */
        glXMakeCurrent(ourdisplay, gwind, gctx);
        glEnable(GL_DEPTH_TEST);
        glDepthFunc(GL_LEQUAL);
        glEnable(GL_DITHER);
        glFrontFace(GL_CCW);
        glDisable(GL_CULL_FACE);
        glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, GL_TRUE);
        glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
                                        /* figure out sensible view */
        pwidth = (double)DisplayWidthMM(ourdisplay, ourscreen) /
                        DisplayWidth(ourdisplay, ourscreen);
        pheight = (double)DisplayHeightMM(ourdisplay, ourscreen) /
                        DisplayHeight(ourdisplay, ourscreen);
#ifdef STEREO
        pheight *= 2.;
        setstereobuf(STEREO_BUFFER_LEFT);
#endif
        checkglerr("setting rendering parameters");
        copystruct(&odev.v, &stdview);
        odev.v.type = VT_PER;
        headlocked = 0;                 /* free up head movement */
        viewsteady = 1;                 /* view starts static */
        isperspective = -1;             /* but no view set, yet */
                                        /* map the window */
        XMapWindow(ourdisplay, gwind);
        dev_input();                    /* sets size and view angles */
        if (!odInit(DisplayWidth(ourdisplay,ourscreen) *
                        DisplayHeight(ourdisplay,ourscreen) / 4))
                error(SYSTEM, "insufficient memory for value storage");
        odev.name = id;
        odev.firstuse = 1;              /* can't recycle samples */
        odev.ifd = ConnectionNumber(ourdisplay);
}


dev_close()                     /* close our display and free resources */
{
#ifdef DOBJ
        dobj_cleanup();
#endif
        freedepth();
        gmEndGeom();
        gmEndPortal();
        odDone();
        glXMakeCurrent(ourdisplay, None, NULL);
        glXDestroyContext(ourdisplay, gctx);
        XDestroyWindow(ourdisplay, gwind);
        gwind = 0;
        XCloseDisplay(ourdisplay);
        ourdisplay = NULL;
        tmDone(NULL);
        odev.v.type = 0;
        odev.hres = odev.vres = 0;
        odev.ifd = -1;
}


dev_clear()                     /* clear our representation */
{
        wipeclean();
        rayqleft = 0;                   /* hold off update */
}


int
dev_view(nv)                    /* assign new driver view */
register VIEW   *nv;
{
        double  d;

        if (nv->type != VT_PER ||               /* 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 != &odev.v) {
                                                /* resize window? */
                if (!FEQ(nv->horiz,odev.v.horiz) ||
                                !FEQ(nv->vert,odev.v.vert)) {
                        int     dw = DisplayWidth(ourdisplay,ourscreen);
                        int     dh = DisplayHeight(ourdisplay,ourscreen);

                        dw -= 25;       /* for window frame */
                        dh -= 50;
#ifdef STEREO
                        dh /= 2;
#endif
                        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);        /* setview() already called */
#ifdef STEREO
                copystruct(&vwright, nv);
                d = eyesepdist / sqrt(nv->hn2);
                VSUM(vwright.vp, nv->vp, nv->hvec, d);
                /* setview(&vwright);   -- Unnecessary */
#endif
        }
        wipeclean();
        return(1);
}


dev_section(gfn, pfn)           /* add octree for geometry rendering */
char    *gfn, *pfn;
{
        extern char     *index();
        char    *cp;

        if (gfn == NULL) {
                gmEndGeom();
                gmEndPortal();
                wipeclean();            /* new geometry, so redraw it */
                return;
        }
        if (access(gfn, R_OK) == 0)
                gmNewGeom(gfn);
#ifdef DEBUG
        else {
                sprintf(errmsg, "cannot load octree \"%s\"", gfn);
                error(WARNING, errmsg);
        }
#endif
        if (pfn != NULL)
                gmNewPortal(pfn);
}


dev_auxcom(cmd, args)           /* process an auxiliary command */
char    *cmd, *args;
{
#ifdef DOBJ
        if (dobj_command(cmd, args) >= 0)
                return;
#endif
        sprintf(errmsg, "%s: unknown command", cmd);
        error(COMMAND, errmsg);
}


VIEW *
dev_auxview(n, hvres)           /* return nth auxiliary view */
int     n;
int     hvres[2];
{
        hvres[0] = odev.hres; hvres[1] = odev.vres;
        if (n == 0)
                return(&odev.v);
#ifdef STEREO
        if (n == 1)
                return(&vwright);
#endif
        return(NULL);
}


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

        do
                getevent();

        while (XPending(ourdisplay) > 0);

        odev.inpready = 0;

        return(inpresflags);
}


dev_value(c, d, p)              /* add a pixel value to our texture */
COLR    c;
FVECT   d, p;
{
#ifdef DOBJ
        if (dobj_lightsamp != NULL) {   /* in light source sampling */
                (*dobj_lightsamp)(c, d, p);
                return;
        }
#endif
        odSample(c, d, p);              /* add to display representation */
        if (!--rayqleft)
                dev_flush();            /* flush output */
}


int
dev_flush()                     /* flush output as appropriate */
{
        int     ndrawn;

        if (mapped && isperspective > 0) {
#ifdef STEREO
                pushright();                    /* draw right eye */
                ndrawn = gmDrawGeom();
#ifdef DOBJ
                ndrawn += dobj_render();
#endif
                if (ndrawn && gmPortals)
                        gmDrawPortals(PORTRED,PORTGRN,PORTBLU,PORTALP);
                checkglerr("rendering right eye");
                popright();                     /* draw left eye */
#endif
                ndrawn = gmDrawGeom();
#ifdef DOBJ
                ndrawn += dobj_render();
#endif
                if (ndrawn && gmPortals)
                        gmDrawPortals(PORTRED,PORTGRN,PORTBLU,PORTALP);
                glXSwapBuffers(ourdisplay, gwind);
                checkglerr("rendering base view");
        }
        if (mapped && viewsteady)
                if (isperspective > 0) {        /* first time after steady */
                        if (ndrawn)
                                xferdepth();    /* transfer and clear depth */
                        setglortho();           /* set orthographic view */
                } else if (!isperspective) {
#ifdef STEREO
                        pushright();
                        odUpdate(1);            /* draw right eye */
                        popright();
#endif
                        odUpdate(0);            /* draw left eye */
                        glFlush();              /* flush OpenGL */
                }
        rayqleft = RAYQLEN;
                                        /* flush X11 and return # pending */
        return(odev.inpready = XPending(ourdisplay));
}


checkglerr(where)               /* check for GL or GLU error */
char    *where;
{
        register GLenum errcode;

        while ((errcode = glGetError()) != GL_NO_ERROR) {
                sprintf(errmsg, "OpenGL error %s: %s",
                                where, gluErrorString(errcode));
                error(WARNING, errmsg);
        }
}


static
xferdepth()                     /* load and clear depth buffer */
{
        register GLfloat        *dbp;
        register GLubyte        *cbuf;

        if (depthbuffer == NULL) {      /* allocate private depth buffer */
#ifdef STEREO
                depthright = (GLfloat *)malloc(
                                odev.hres*odev.vres*sizeof(GLfloat));
#endif
                depthbuffer = (GLfloat *)malloc(
                                odev.hres*odev.vres*sizeof(GLfloat));
                CHECK(depthbuffer==NULL, SYSTEM, "out of memory in xferdepth");
        }
                                /* allocate alpha buffer for portals */
        if (gmPortals)
                cbuf = (GLubyte *)malloc(odev.hres*odev.vres *
                                                        (4*sizeof(GLubyte)));
        else
                cbuf = NULL;
#ifdef STEREO
        setstereobuf(STEREO_BUFFER_RIGHT);
        glReadPixels(0, 0, odev.hres, odev.vres,
                        GL_DEPTH_COMPONENT, GL_FLOAT, depthright);
        if (cbuf != NULL)
                glReadPixels(0, 0, odev.hres, odev.vres,
                                GL_RGBA, GL_UNSIGNED_BYTE, cbuf);
        for (dbp = depthright + odev.hres*odev.vres; dbp-- > depthright; )
                if (cbuf != NULL && isportal(cbuf+4*(dbp-depthright)))
                        *dbp = FHUGE;
                else
                        *dbp = mapdepth(*dbp);
        glClear(GL_DEPTH_BUFFER_BIT);
        setstereobuf(STEREO_BUFFER_LEFT);
        odDepthMap(1, depthright);
#endif
                                /* read back depth buffer */
        glReadPixels(0, 0, odev.hres, odev.vres,
                        GL_DEPTH_COMPONENT, GL_FLOAT, depthbuffer);
        if (cbuf != NULL)
                glReadPixels(0, 0, odev.hres, odev.vres,
                                GL_RGBA, GL_UNSIGNED_BYTE, cbuf);
        for (dbp = depthbuffer + odev.hres*odev.vres; dbp-- > depthbuffer; )
                if (cbuf != NULL && isportal(cbuf+4*(dbp-depthbuffer)))
                        *dbp = FHUGE;
                else
                        *dbp = mapdepth(*dbp);
        glClear(GL_DEPTH_BUFFER_BIT);           /* clear system depth buffer */
        if (cbuf != NULL)
                free((char *)cbuf);             /* free our color buffer */
        odDepthMap(0, depthbuffer);             /* transfer depth data */
}


static
freedepth()                             /* free recorded depth buffer */
{
        if (depthbuffer == NULL)
                return;
#ifdef STEREO
        odDepthMap(1, NULL);
        free((char *)depthright);
        depthright = NULL;
#endif
        odDepthMap(0, NULL);
        free((char *)depthbuffer);
        depthbuffer = NULL;
}


static double
getdistance(dx, dy, direc)      /* distance from fore plane along view ray */
int     dx, dy;
FVECT   direc;
{
        GLfloat gldepth;
        GLubyte glcolor[4];
        double  dist;

        if (dx<0 | dx>=odev.hres | dy<0 | dy>=odev.vres)
                return(FHUGE);
        if (depthbuffer != NULL)
                dist = depthbuffer[dy*odev.hres + dx];
        else {
                glReadPixels(dx,dy, 1,1, GL_DEPTH_COMPONENT,
                                GL_FLOAT, &gldepth);
                if (gmPortals) {
                        glReadPixels(dx,dy, 1,1, GL_RGBA,
                                        GL_UNSIGNED_BYTE, glcolor);
                        if (isportal(glcolor))
                                return(FHUGE);
                }
                dist = mapdepth(gldepth);
        }
        if (dist >= .99*FHUGE)
                return(FHUGE);
        return((dist-odev.v.vfore)/DOT(direc,odev.v.vdir));
}


#ifdef STEREO
static
pushright()                     /* push on right view & buffer */
{
        double  d;

        setstereobuf(STEREO_BUFFER_RIGHT);
        if (isperspective > 0) {
                glMatrixMode(GL_MODELVIEW);
                glPushMatrix();
                d = -eyesepdist / sqrt(odev.v.hn2);
                glTranslated(d*odev.v.hvec[0], d*odev.v.hvec[1],
                                d*odev.v.hvec[2]);
                checkglerr("setting right view");
        }
}


static
popright()                      /* pop off right view & buffer */
{
        if (isperspective > 0) {
                glMatrixMode(GL_MODELVIEW);
                glPopMatrix();
        }
        setstereobuf(STEREO_BUFFER_LEFT);
}
#endif


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++)
                ;
#ifdef DEBUG
        if (cp > tail && cp[-1] == 'h')
                return(TM_F_HUMAN);
        else
                return(TM_F_CAMERA);
#else
        if (cp > tail && cp[-1] == 'h')
                return(TM_F_HUMAN|TM_F_NOSTDERR);
        else
                return(TM_F_CAMERA|TM_F_NOSTDERR);
#endif
}


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:
                odRemap(0);
                mapped = 1;
                break;
        case Expose:
                fixwindow(levptr(XExposeEvent));
                break;
        case KeyPress:
                getkey(levptr(XKeyPressedEvent));
                break;
        case ButtonPress:
                if (FRAMESTATE(levptr(XButtonPressedEvent)->state))
                        getframe(levptr(XButtonPressedEvent));
                else
                        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(fore)                /* draw holodeck section grids */
int     fore;
{
        glPushAttrib(GL_LIGHTING_BIT|GL_ENABLE_BIT);
        glDisable(GL_LIGHTING);
        if (fore)
                glColor3ub(0, 255, 255);
        else
                glColor3ub(0, 0, 0);
        glBegin(GL_LINES);              /* draw each grid line */
        gridlines(draw3dline);
        glEnd();
        checkglerr("drawing grid lines");
        glPopAttrib();
}


static
moveview(dx, dy, mov, orb)      /* move our view */
int     dx, dy, mov, orb;
{
        VIEW    nv;
        FVECT   odir, v1, wip;
        double  d, d1;
        register int    li;
                                /* start with old view */
        copystruct(&nv, &odev.v);
                                /* orient our motion */
        if (viewray(v1, odir, &odev.v,
                        (dx+.5)/odev.hres, (dy+.5)/odev.vres) < -FTINY)
                return(0);              /* outside view */
        if (mov | orb) {        /* moving relative to geometry */
                d = getdistance(dx, dy, odir);  /* distance from front plane */
#ifdef DOBJ
                d1 = dobj_trace(NULL, v1, odir);
                if (d1 < d)
                        d = d1;
#endif
                if (d >= .99*FHUGE)
                        d = 0.5*(dev_zmax+dev_zmin);    /* just guess */
                VSUM(wip, v1, odir, d);
                VSUB(odir, wip, odev.v.vp);
        } else                  /* panning with constant viewpoint */
                VCOPY(nv.vdir, odir);
        if (orb && mov) {               /* orbit left/right */
                spinvector(odir, odir, nv.vup, d=MOVDEG*PI/180.*mov);
                VSUM(nv.vp, wip, 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, wip, 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, nv.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
getframe(ebut)                          /* get focus frame */
XButtonPressedEvent     *ebut;
{
        int     startx = ebut->x, starty = ebut->y;
        int     endx, endy;

        XMaskEvent(ourdisplay, ButtonReleaseMask, levptr(XEvent));
        endx = levptr(XButtonReleasedEvent)->x;
        endy = levptr(XButtonReleasedEvent)->y;
        if (endx == startx | endy == starty) {
                XBell(ourdisplay, 0);
                return;
        }
        if (endx < startx) {register int c = endx; endx = startx; startx = c;}
        if (endy < starty) {register int c = endy; endy = starty; starty = c;}
        sprintf(odev_args, "%.3f %.3f %.3f %.3f",
                        (startx+.5)/odev.hres, 1.-(endy+.5)/odev.vres,
                        (endx+.5)/odev.hres, 1.-(starty+.5)/odev.vres);
        inpresflags |= DFL(DC_FOCUS);
}


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

        XNoOp(ourdisplay);              /* makes sure we're not idle */

        viewsteady = 0;                 /* flag moving view */
        setglpersp(&odev.v);            /* start us off in perspective */
        while (!XCheckMaskEvent(ourdisplay,
                        ButtonReleaseMask, levptr(XEvent))) {
                                        /* get cursor position */
                if (!XQueryPointer(ourdisplay, gwind, &rootw, &childw,
                                &rootx, &rooty, &wx, &wy, &statemask))
                        break;          /* on another screen */
                                        /* compute view motion */
                if (!moveview(wx, odev.vres-1-wy, movdir, movorb)) {
                        sleep(1);
                        continue;       /* cursor in bad place */
                }
                draw_grids(1);          /* redraw grid */
#ifdef STEREO
                pushright();
                draw_grids(1);
                ndrawn = gmDrawGeom();
#ifdef DOBJ
                ndrawn += dobj_render();
#endif
                if (ndrawn && gmPortals)
                        gmDrawPortals(PORTRED,PORTGRN,PORTBLU,PORTALP);
                popright();
#endif
                                        /* redraw octrees */
                ndrawn = gmDrawGeom();
#ifdef DOBJ
                ndrawn += dobj_render();        /* redraw objects */
#endif
                if (ndrawn && gmPortals)
                        gmDrawPortals(PORTRED, PORTGRN, PORTBLU, PORTALP);
                glXSwapBuffers(ourdisplay, gwind);
                if (!ndrawn)
                        sleep(1);       /* for reasonable interaction */
        }
        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);
        }
        viewsteady = 1;                 /* done goofing around */
}


static
setglpersp(vp)                  /* set perspective view in GL */
register VIEW   *vp;
{
        double  d, xmin, xmax, ymin, ymax;
        GLfloat vec[4];
        double  depthlim[2];
                                        /* set depth limits */
        gmDepthLimit(depthlim, odev.v.vp, odev.v.vdir);
        if (depthlim[0] >= depthlim[1]) {
                dev_zmin = 1.;
                dev_zmax = 100.;
        } else {
                dev_zmin = 0.5*depthlim[0];
                dev_zmax = 1.75*depthlim[1];
                if (dev_zmin > dev_zmax/5.)
                        dev_zmin = dev_zmax/5.;
        }
        if (odev.v.vfore > FTINY)
                dev_zmin = odev.v.vfore;
        if (odev.v.vaft > FTINY)
                dev_zmax = odev.v.vaft;
        if (dev_zmin < dev_zmax/100.)
                dev_zmin = dev_zmax/100.;
        setzrat();
        xmax = dev_zmin * tan(PI/180./2. * odev.v.horiz);
        xmin = -xmax;
        d = odev.v.hoff * (xmax - xmin);
        xmin += d; xmax += d;
        ymax = dev_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);
        glLoadIdentity();
        glFrustum(xmin, xmax, ymin, ymax, dev_zmin, dev_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]);
        checkglerr("setting perspective view");
        isperspective = 1;
        vec[0] = vec[1] = vec[2] = 0.; vec[3] = 1.;
        glLightModelfv(GL_LIGHT_MODEL_AMBIENT, vec);
        vec[0] = -odev.v.vdir[0];
        vec[1] = -odev.v.vdir[1];
        vec[2] = -odev.v.vdir[2];
        vec[3] = 0.;
        glLightfv(GL_LIGHT0, GL_POSITION, vec);
        vec[0] = vec[1] = vec[2] = .7; vec[3] = 1.;
        glLightfv(GL_LIGHT0, GL_SPECULAR, vec);
        glLightfv(GL_LIGHT0, GL_DIFFUSE, vec);
        vec[0] = vec[1] = vec[2] = .3; vec[3] = 1.;
        glLightfv(GL_LIGHT0, GL_AMBIENT, vec);
        glEnable(GL_LIGHT0);
        glEnable(GL_LIGHTING);          /* light our GL objects */
        glShadeModel(GL_SMOOTH);
}


static
setglortho()                    /* set up orthographic view for cone drawing */
{
        glDrawBuffer(GL_FRONT);         /* use single-buffer mode */
                                        /* set view matrix */
        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();
        glOrtho(0., (double)odev.hres, 0., (double)odev.vres,
                        0.001*OMAXDEPTH, 1.001*(-OMAXDEPTH));
        checkglerr("setting orthographic view");
        isperspective = 0;
        glDisable(GL_LIGHTING);         /* cones are constant color */
        glShadeModel(GL_FLAT);
}


static
wipeclean()                     /* prepare for redraw */
{
        glDrawBuffer(GL_BACK);          /* use double-buffer mode */
                                        /* clear buffers */
#ifdef STEREO
        setstereobuf(STEREO_BUFFER_RIGHT);
        glClear(GL_DEPTH_BUFFER_BIT|GL_COLOR_BUFFER_BIT);
        setstereobuf(STEREO_BUFFER_LEFT);
#endif
        glClear(GL_DEPTH_BUFFER_BIT|GL_COLOR_BUFFER_BIT);
        freedepth();
        if (viewsteady)                 /* clear samples if steady */
                odClean();
        setglpersp(&odev.v);            /* reset view & clipping planes */
}


static
getkey(ekey)                            /* get input key */
register XKeyPressedEvent  *ekey;
{
        Window  rootw, childw;
        int     rootx, rooty, wx, wy;
        unsigned int    statemask;
        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 'f':                       /* frame view position */
                if (!XQueryPointer(ourdisplay, gwind, &rootw, &childw,
                                &rootx, &rooty, &wx, &wy, &statemask))
                        return;         /* on another screen */
                sprintf(odev_args, "%.4f %.4f", (wx+.5)/odev.hres,
                                1.-(wy+.5)/odev.vres);
                inpresflags |= DFL(DC_FOCUS);
                return;
        case 'F':                       /* unfocus */
                odev_args[0] = '\0';
                inpresflags |= DFL(DC_FOCUS);
                return;
        case '\n':
        case '\r':                      /* resume computation */
                inpresflags |= DFL(DC_RESUME);
                return;
        case CTRL('R'):                 /* redraw screen */
                odRemap(0);
                glClear(GL_DEPTH_BUFFER_BIT);
#ifdef STEREO
                setstereobuf(STEREO_BUFFER_RIGHT);
                glClear(GL_DEPTH_BUFFER_BIT);
                setstereobuf(STEREO_BUFFER_LEFT);
#endif
                return;
        case CTRL('L'):                 /* refresh from server */
                if (inpresflags & DFL(DC_REDRAW))
                        return;
                XRaiseWindow(ourdisplay, gwind);
                XFlush(ourdisplay);
                sleep(1);
                wipeclean();                    /* fresh display */
                odRemap(1);                     /* fresh tone mapping */
                dev_flush();                    /* draw octrees */
                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, ymin, xmax, ymax;

        if (odev.hres == 0 | odev.vres == 0) {  /* first exposure */
                resizewindow((XConfigureEvent *)eexp);
                return;
        }
        xmin = eexp->x; xmax = eexp->x + eexp->width;
        ymin = odev.vres - eexp->y - eexp->height; ymax = odev.vres - eexp->y;
                                                /* clear portion of depth */
        glPushAttrib(GL_DEPTH_BUFFER_BIT|GL_COLOR_BUFFER_BIT);
        glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
        glDepthFunc(GL_ALWAYS);
        glBegin(GL_POLYGON);
        glVertex3i(xmin, ymin, OMAXDEPTH);
        glVertex3i(xmax, ymin, OMAXDEPTH);
        glVertex3i(xmax, ymax, OMAXDEPTH);
        glVertex3i(xmin, ymax, OMAXDEPTH);
        glEnd();
#ifdef STEREO
        setstereobuf(STEREO_BUFFER_RIGHT);
        glBegin(GL_POLYGON);
        glVertex3i(xmin, ymin, OMAXDEPTH);
        glVertex3i(xmax, ymin, OMAXDEPTH);
        glVertex3i(xmax, ymax, OMAXDEPTH);
        glVertex3i(xmin, ymax, OMAXDEPTH);
        glEnd();
        odRedraw(1, xmin, ymin, xmax, ymax);
        setstereobuf(STEREO_BUFFER_LEFT);
#endif
        glPopAttrib();
        odRedraw(0, 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:	3.6
Committed:	Mon Dec 21 19:17:28 1998 UTC (25 years, 4 months ago) by gwlarson
Content type:	text/plain
Branch:	MAIN
Changes since 3.5:	+40 -34 lines
Log Message:	switched to double-buffered display