SGI Developer Toolbox 6.1/SGI Developer Toolbox 6.1 - Disc 4.iso/src/exampleCode/inventor/inventorTemplates/walk.c++

C/C++ Source or Header | 1994-08-02 | 6.0 KB | 245 lines

/*
 * Copyright 1992, 1993, 1994, Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This is UNPUBLISHED PROPRIETARY SOURCE CODE of Silicon Graphics, Inc.;
 * the contents of this file may not be disclosed to third parties, copied or
 * duplicated in any form, in whole or in part, without the prior written
 * permission of Silicon Graphics, Inc.
 *
 * RESTRICTED RIGHTS LEGEND:
 * Use, duplication or disclosure by the Government is subject to restrictions
 * as set forth in subdivision (c)(1)(ii) of the Rights in Technical Data
 * and Computer Software clause at DFARS 252.227-7013, and/or in similar or
 * successor clauses in the FAR, DOD or NASA FAR Supplement. Unpublished -
 * rights reserved under the Copyright Laws of the United States.
 */
/*
 * Copyright (C) 1992   Silicon Graphics, Inc.
 *
 _______________________________________________________________________
 ______________  S I L I C O N   G R A P H I C S   I N C .  ____________
 |
 |   $Revision: 1.0000 $
 |
 |   File: walk.c++
 |   Purpose: creates a walk viewer, when the user comes out of viewing
 |            mode and hits the d key, information about the camera
 |            location gets spit out, this is useful for creating
 |            animation files to be played with the player program
 |
 |   Author(s)          : Kevin Goldsmith
 |
 ______________  S I L I C O N   G R A P H I C S   I N C .  ____________
 _______________________________________________________________________
 */




#include <assert.h>
#include <getopt.h>

#include <Inventor/Xt/SoXt.h>
#include <Inventor/Xt/viewers/SoXtWalkViewer.h>
#include <Inventor/nodes/SoNode.h>
#include <Inventor/nodes/SoSeparator.h>
#include <Inventor/nodes/SoPerspectiveCamera.h>
#include <Inventor/SoDB.h>
#include <Inventor/nodes/SoCallback.h>
#include <Inventor/actions/SoHandleEventAction.h>
#include <Inventor/events/SoKeyboardEvent.h>

SoCamera *camera = NULL;

static char *filename = NULL;
static char *envfile = NULL;

void
CreateCamera(SoGroup *root)
{
    SoPerspectiveCamera *pc = new SoPerspectiveCamera;
      pc->ref();
    camera = pc;
    root->insertChild(pc, 0);
}

//
// Read a file given a filename and return a separator containing all
// of the stuff in the file.
// --- stolen mostly from Gavin Bell
//
SoSeparator *
readFile(const char *filename)
{
    SoInput in;
    if (filename != NULL)
    {
    if (in.openFile(filename) == FALSE)
    {
        fprintf(stderr, "Could not open file %s\n", filename);
        return NULL;
    }
    }

    SoSeparator *graph = new SoSeparator;
    graph->ref();

    //
    // Keep on reading until there are no more nodes to read
    //
    SoNode *root;
    do
    {
    int read_ok = SoDB::read(&in, root);

    if (!read_ok)
    {
        fprintf(stderr, "Error reading file\n");
        graph->unref();
        return NULL;
    }
    else if (root != NULL) graph->addChild(root);

    } while (root != NULL);
    in.closeFile();

    //
    // Try to avoid creating extra separators; if this scene graph
    // already has exactly one separator at the top, use it.  This
    // will avoid an explosion of separators at the top of scenes that
    // would otherwise occur if we automatically created a new
    // separator every time a scene graph was read.
    //
    if (graph->getNumChildren() == 1 &&
    graph->getChild(0)->isOfType(SoSeparator::getClassTypeId()))
    {
    SoSeparator *result = (SoSeparator *)graph->getChild(0);
    result->ref();    // Note the order here!
    graph->unref();

    result->unrefNoDelete();
    return result;
    }

    graph->unrefNoDelete();
    return graph;

}

// did the user press the key we want?
static void checkKey(void *, SoAction *action)
{
    if (action->getTypeId().
     isDerivedFrom(SoHandleEventAction::getClassTypeId())) {
    const SoEvent *e = ((SoHandleEventAction *)action)->getEvent();

    // did the user hit the d?
    if (SO_KEY_PRESS_EVENT(e, D)) {
        assert(camera != NULL);
        SbVec3f pos;
        pos = camera->position.getValue();

        SbVec3f axis;
        float angle;

        camera->orientation.getValue(axis, angle);
        printf("%f %f %f %f %f %f %f\n", pos[0],
           pos[1], pos[2], axis[0], axis[1], axis[2], angle);
    }
    }
}


// get user flags
static void
parseCommandLine(int argc, char **argv)
{
    int err = 0;    // Flag: error in options?
    int c;

    while ((c = getopt(argc, argv, "e:")) != -1)
    {
    switch(c)
    {
      case 'e': envfile = optarg; break;
      default:
        err = 1;
        break;
    }
    }
    if (optind+1 != argc) err = 1;

    filename = argv[optind];

    if (err)
    {
    fprintf(stderr, "Usage: %s "
              "[-e envfile] filename\n", argv[0]);
    fprintf(stderr, "-e : Reads given environment file\n");
    exit(99);
    }
}



main( int argc, char **argv )
{
    parseCommandLine(argc, argv);

    Widget top = SoXt::init(argv[0]);
    if (top == NULL)
    {
    fprintf(stderr, "%s: Couldn't open top-level widget\n", argv[0]);
    exit(1);
    }

    // create the viewer
    SoXtWalkViewer *ra = new SoXtWalkViewer(top);

    // create the root of the subgraph
    SoSeparator *root = new SoSeparator;
    root->ref();

    // create a callback to see if we get the key
    SoCallback *callback = new SoCallback;
    callback->setCallback(checkKey);
    root->addChild(callback);


    // the user wants to start at an envfile
    if (envfile != NULL)
    {
    SoSeparator *env = readFile(envfile);
    if (env == NULL) exit(1);
    env->ref();
    for (int i = 0; i < env->getNumChildren(); i++)
    {
        root->addChild(env->getChild(i));
        if (env->getChild(i)->isOfType(SoCamera::getClassTypeId()))
        camera = (SoCamera *)env->getChild(i);
    }
    env->unref();
    } else
      CreateCamera(root); // otherwise we create our own camera

    // read in the inventor file
    SoSeparator *stuff = readFile(filename);
    if (stuff == NULL) exit(1); // it was empty!!
    root->addChild(stuff);      // or it was not

    // set some stuff on the render area
    ra->setSceneGraph(root);
    ra->setHeadlight(TRUE);
    ra->setDecoration(TRUE);

    //show the viewer
    ra->show();

    // show the window
    SoXt::show(top);

    // let Inventor take care of the rest
    SoXt::mainLoop();
}