//<copyright>
// 
// Copyright (c) 1995
// Institute for Information Processing and Computer Supported New Media (IICM),
// Graz University of Technology, Austria.
// 
//</copyright>

//<file>
//
// Name:        wrlbuild.C
//
// Purpose:     preprocessing of VRML nodes
//
// Created:      2 May 95   Michael Pichler
//
// Changed:     24 Oct 95   Michael Pichler
//
//
//</file>

#ifdef __PC__
#include "stdafx.h"
#endif


#if defined(PMAX) || defined (HPUX9)
enum Part { goofyPart };        // cfront confused about QvCone::Part and QvCylinder::Part
enum Binding { goofyBinding };  // cfront confused about QvMaterialBinding/QvNormalBinding::Binding
#endif


#include <vrml/QvElement.h>
#include <vrml/QvNodes.h>
#include <vrml/QvExtensions.h>
#include <vrml/QvUnknownNode.h>
#include <vrml/QvDebugError.h>
#include <vrml/QvState.h>

#include "scene3d.h"
#include "vrmlscene.h"
#include "vecutil.h"

#include <ge3d/ge3d.h>

#include <hyperg/hyperg/verbose.h>

#include <stdio.h>
#include <iostream.h>
#include <math.h>

// convert radians to degrees
#define DEGREES(R)  ( (R) * (180 / M_PI) )

// special names (info nodes)
#define BACKGROUND_INFO "BackgroundColor"
#define VIEWER_INFO "Viewer"

// predefined viewpoints
#define CAMERAS_SWITCH "Cameras"


// important: to set up correct bounding boxes, all transfomation
// stuff must be done in build too (check for ge3d functions that do
// matrix transformations)

// a word about multiple instancing: the computed world bounding box
// will be overwritten by subsequent instances and is therefore *not*
// valid in draw; generally: all information stored in build stays
// only valid if it is local to the node and when it does not depend
// from the traversal state

// TODO: check for multiple instances if state dependend variables
// need to be stored - strictly taken this already happens with
// IndexedFaceSet that has to use the current point array etc.

// world bounding wmin_/wmax_ are only valid during build
// (may be overwritten on multiple instances);
// due to this fact world bounding boxes have been changed
// to be local to separators (mpichler, 19951006);
// object bounding box omin_/omax_ remains valid throughout (if
// defined at all)


// current cameras switch node
static QvSwitch* camswitch = 0;
static int camswindex = 0;



/***** groups *****/

void QvGroup::build (QvState* state)
{
  int n = getNumChildren ();
  QvNode* child;
  point3D& wmin = wmin_;
  point3D& wmax = wmax_;

  emptyBoundingbox (wmin, wmax);

  // if any child has an extent, then a group node has the extent of
  // the unions of all bounding boxes (all in world coordinates)

  for (int i = 0; i < n; i++)
  {
    child = getChild (i);
    child->build (state);
    if (child->hasextent_)
    {
      hasextent_ = 1;
      extendBoundingbox (child->wmin_, child->wmax_, wmin, wmax);
    }
  } // for all children

  if (hasextent_)   // (for Separator)
  { omin_ = wmin_;  // no object bounding box defined for Groups
    omax_ = wmax_;  // (dependent on current transformation)
  }
} // QvGroup


void QvLOD::build (QvState* state)
{
  center_ = (const point3D*) &center.value;
  QvGroup::build (state);  // preprocessing of all children
}


void QvSeparator::build (QvState* state)
{
  state->push ();  // push attribute stacks
  ge3dPushIdentity ();

  // set object boundig to union of children's world boundings
  QvGroup::build (state);

  //cerr << "QvSeparator::build: pop ()" << endl;
  ge3d_pop_matrix ();
  state->pop ();  // pop stacks (cleans up)

  if (hasextent_)
    computeBoundingbox (omin_, omax_, wmin_, wmax_);  // applies current transformation
}


void QvSwitch::build (QvState* state)
{
  const char* name = objName->getString ();  // objName non nil

  if (!name || strcmp (name, CAMERAS_SWITCH))  // ordinary Switch
  {
    QvGroup::build (state);  // preprocessing of all children
    return;
  }

  // camera switch; like QvGroup::build, but cameras need to know their index
  camswitch = this;

  int n = getNumChildren ();
  QvNode* child;
  point3D& wmin = wmin_;
  point3D& wmax = wmax_;

  emptyBoundingbox (wmin, wmax);

  // if any child has an extent, then a group node has the extent of
  // the unions of all bounding boxes (all in world coordinates)

  for (int i = 0; i < n; i++)
  {
    camswindex = i;
    child = getChild (i);
    child->build (state);
    if (child->hasextent_)
    {
      hasextent_ = 1;
      extendBoundingbox (child->wmin_, child->wmax_, wmin, wmax);
    }
  } // for all children

  if (hasextent_)
  { omin_ = wmin_;
    omax_ = wmax_;
  }

  camswitch = 0;
  camswindex = 0;

} // QvSwitch


void QvTransformSeparator::build (QvState* state)
{
  // like Separator, except that state is not pushed
  // TODO: may compute a cumulative transformation

  ge3dPushIdentity ();

  QvGroup::build (state);

  ge3d_pop_matrix ();

  if (hasextent_)
    computeBoundingbox (omin_, omax_, wmin_, wmax_);  // applies current transformation
}


/***** coordinates *****/


void QvCoordinate3::build (QvState* state)
{
  QvElement* el = new QvElement;  // stack elements are deleted in stack pop of Separator
  el->data = this;
  state->addElement (QvState::Coordinate3Index, el);

  int n = point.num;
  if (!n)  // pathologic: empty coordinate list
  { init3D (omin_, 0, 0, 0);
    omax_ = omin_;
    return;
  }

  point3D& min = omin_;
  point3D& max = omax_;
  emptyBoundingbox (min, max);

  const point3D* vert = (const point3D*) point.values;
  while (n--)
  {
    // cerr << "point " << *vert << endl;
    extendBoundingbox (*vert, *vert, min, max);
    vert++;
  }

  // cerr << "coordinate3 boundings: " << omin_ << ", " << omax_ << endl;

  // a Coordinate3 node has *no* extent itself, only shapes that use
  // it (which must transform the boundings into world coordinates -
  // transformations may be applied after specifying the coordinates)
} // QvCoordinate3


void QvNormal::build (QvState* state)
{
  QvElement* el = new QvElement;
  el->data = this;
  state->addElement (QvState::NormalIndex, el);
}


void QvTextureCoordinate2::build (QvState* state)
{
  QvElement* el = new QvElement;
  el->data = this;
  state->addElement (QvState::TextureCoordinate2Index, el);
}



/***** properties *****/


#define BUILD(className)  \
void className::build (QvState*)  { }


// mapping of QvMaterialBinding to ge3d_matbinding_t
// be sure to match order of QvMaterialBinding::Binding

int ge3dMatBindings [QvMaterialBinding::PER_VERTEX_INDEXED + 1] =
{ matb_default,
  matb_overall,
  matb_perpart,
  matb_perpartindexed,
  matb_perface,
  matb_perfaceindexed,
  matb_pervertex,
  matb_pervertexindexed
};


BUILD(QvFontStyle)

void QvMaterial::build (QvState* state)
{
  // material definition arrays
  materialsGE3D& mats = materials_;

  mats.num_ambient = ambientColor.num;
  mats.num_diffuse = diffuseColor.num;
  mats.num_specular = specularColor.num;
  mats.num_emissive = emissiveColor.num;
  mats.num_shininess = shininess.num;
  mats.num_transparency = transparency.num;

  mats.rgb_ambient = (const colorRGB*) ambientColor.values;
  mats.rgb_diffuse = (const colorRGB*) diffuseColor.values;
  mats.rgb_specular = (const colorRGB*) specularColor.values;
  mats.rgb_emissive = (const colorRGB*) emissiveColor.values;
  mats.val_shininess = shininess.values;
  mats.val_transparency = transparency.values;

  // first ("base") material definitions (used for overall binding)
  // might leave out default settings (but then had to care for push/pop)

  float alpha = 1.0;
  if (transparency.num)
    alpha = 1.0 - *transparency.values;
  // cerr << "material transparency: " << 1.0 - alpha << " (alpha: " << alpha << ")" << endl;

  float* def = matdef_;
  const float* rgbval;

  if (ambientColor.num)
  { rgbval = ambientColor.values;
    // cerr << "ambient color " << rgbval [0] << ", " << rgbval [1] << ", " << rgbval [2] << endl;
    *def++ = mat_ambientRGBA;  // 0
    *def++ = rgbval [0];  *def++ = rgbval [1];  *def++ = rgbval [2];  *def++ = alpha;  // 1 - 4
  }
  if (diffuseColor.num)
  { rgbval = diffuseColor.values;
    // cerr << "diffuse color " << rgbval [0] << ", " << rgbval [1] << ", " << rgbval [2] << endl;
    *def++ = mat_diffuseRGBA;  // 5
    *def++ = rgbval [0];  *def++ = rgbval [1];  *def++ = rgbval [2];  *def++ = alpha;  // 6 - 9
  }
  if (specularColor.num)
  { rgbval = specularColor.values;
    // cerr << "specular color " << rgbval [0] << ", " << rgbval [1] << ", " << rgbval [2] << endl;
    *def++ = mat_specularRGBA;  // 10
    *def++ = rgbval [0];  *def++ = rgbval [1];  *def++ = rgbval [2];  *def++ = alpha;  // 11 - 14
  }

  // TODO: this will not turn off an emissive color on separator, better use an
  // extra basecolor_ for diffuse/emissive component to be used for wireframes

  if (emissiveColor.num)
  { rgbval = emissiveColor.values;
    // cerr << "emissive color " << rgbval [0] << ", " << rgbval [1] << ", " << rgbval [2] << endl;
    if (rgbval [0] || rgbval [1] || rgbval [2])
    {
      *def++ = mat_emissiveRGBA;  // 15
      *def++ = rgbval [0];  *def++ = rgbval [1];  *def++ = rgbval [2];  *def++ = alpha;  // 16 - 19
    }
  }
  if (shininess.num)
  {
    // cerr << "shininess value: " << *shininess.values << endl;
    *def++ = mat_shininessValue;  // 20
    if (*shininess.values < 0.0 || *shininess.values > 1.0)
    { QvDebugError::post ("Material", "shininess value out of range (allowed: 0.0 to 1.0)");
      *def++ = 0.2;  // using default value
    }
    else
      *def++ = *shininess.values;  // in range 0.0 to 1.0 (as opposed to (Open)GL)
  }
  *def = mat_END;  // 22

  QvElement* el = new QvElement;
  el->data = this;
  state->addElement (QvState::MaterialIndex, el);
} /* QvMaterial */


void QvMaterialBinding::build (QvState* state)
{
  QvElement* el = new QvElement;
  el->data = this;
  state->addElement (QvState::MaterialBindingIndex, el);
}


BUILD(QvNormalBinding)  // TODO


void QvShapeHints::build (QvState*)
{
  backfaceculling_ = (vertexOrdering.value == COUNTERCLOCKWISE)
                  && (shapeType.value == SOLID);

// TODO: must be undone at end of separator (pushed on stack ShapeHintsIndex)
//cerr << "backfaceculling: " << backfaceculling_ << endl;
}


void QvTexture2::build (QvState*)
{
  if (!freeTexture_)
    freeTexture_ = &ge3dFreeTexture;

  // TODO: handle texture inlines like WWWInlines (on first draw in texturing)
  // TODO: wrapping flag

  if (handle_ < 0)  // set texture handle
  {
    if (filename.value.getLength ())
      cerr << "VRweb: reading texture image from URL " << filename.value.getString ()
           << " not yet implemented." << endl;

    short width = image.size [0];
    short height = image.size [1];
    DEBUGNL ("texture image size (widthxheight): " << width << "x" << height);

    if (width < 1 || height < 1 || !image.bytes)
    {
      cerr << "error in Texture2: nonpositive width or height or no data" << endl;
      handle_ = 0;
      return;
    }

    int texfmt;

    // convert image into ge3d's native format
    // TODO: transparency does not work well with Z-Buffer
    switch (image.numComponents)
    {
      case 1:  // intensity
        texfmt = ge3d_ubyte_I_BT;
      break;
      case 2:  // intensity, alpha
        texfmt = ge3d_ubyte_IA_BT;
      break;
      case 3:  // RGB
        texfmt = ge3d_ubyte_RGB_BT;
      break;
      case 4:  // RGBA
        texfmt = ge3d_ubyte_RGBA_BT;
      break;

      default:
        QvDebugError::post ("Texture2", "invalid value for numComponents (allowed: 1 to 4)");
        handle_ = 0;
      return;
    }

    handle_ = ge3dCreateTexture (width, height, image.bytes, texfmt);
    // cerr << "got texture handle " << handle_ << endl;

  } // if (handle_ < 0)

} // QvTexture2


BUILD(QvTexture2Transform)



/***** lights *****/


void QvDirectionalLight::build (QvState*)
{
  float intens = intensity.value;
  float* col = color.value;
  float* dir = direction.value;

  initRGB (color_, intens * col [0], intens * col [1], intens * col [2]);
  // VRML: vector parallel to light direction
  // GL/ge3d: vector towards light source
  init3D (direction_, - dir [0], - dir [1], - dir [2]);
  vrmlscene_->hasLight ();
}


void QvPointLight::build (QvState*)
{
  float intens = intensity.value;
  float* col = color.value;

  initRGB (color_, intens * col [0], intens * col [1], intens * col [2]);

  position_ = (const point3D*) location.value;
  vrmlscene_->hasLight ();
}


void QvSpotLight::build (QvState*)
{
  float intens = intensity.value;
  float* col = color.value;

  initRGB (color_, intens * col [0], intens * col [1], intens * col [2]);

  position_ = (const point3D*) location.value;
  direction_ = (const vector3D*) direction.value;  // TODO: check whether correct orientation
  cutangle_ = DEGREES (cutOffAngle.value);
  vrmlscene_->hasLight ();
}



/***** cameras *****/


void QvOrthographicCamera::build (QvState*)
{
  // give warning on invalid fields; reset to sentinel
  if (nearDistance.value >= 0 || farDistance.value >= 0)
  {
    QvDebugError::post ("OrthographicCamera", "illegal fields nearDistance/farDistance");
    nearDistance.value = -1;
    farDistance.value = -1;
  }

  pos_ = (const point3D*) position.value;
  rotangle_ = orientation.angle;  // radians
  rotaxis_ = (const vector3D*) orientation.axis;
  height_ = height.value;
// cerr << "orthographic camera: position " << *pos_ << ", rotangle " << rotangle_ << ", rotaxis " << *rotaxis_
// << ", height " << height_ << endl;

  camswitch_ = camswitch;
  camswindex_ = camswindex;
  if (!registered_)
  { vrmlscene_->hasCamera (this, objName->getString ());  // objName non nil
    registered_ = 1;
  }

  ge3dPushIdentity ();
  ge3dRotate (rotaxis_, - rotangle_);
  ge3d_translate (-pos_->x, -pos_->y, -pos_->z);
  ge3d_get_and_pop_matrix (mat_);

  ge3dMultMatrix ((const float (*)[4]) mat_);  // set up transformation (as in draw)
  // draw ();  // set up transformation

  copymatrix (mat_, invmat_);
  invertmatrix (invmat_);
} // QvOrthographicCamera


void QvPerspectiveCamera::build (QvState*)
{
  // give warning on invalid fields; reset to sentinel
  if (nearDistance.value >= 0 || farDistance.value >= 0)
  {
    QvDebugError::post ("PerspectiveCamera", "illegal nodes nearDistance/farDistance");
    nearDistance.value = -1;
    farDistance.value = -1;
  }

  pos_ = (const point3D*) position.value;
  rotangle_ = orientation.angle;  // radians
  rotaxis_ = (const vector3D*) orientation.axis;
  yangle_ = heightAngle.value;  // radians
// cerr << "perspective camera: position " << *pos_ << ", rotangle " << rotangle_ << ", rotaxis " << *rotaxis_
// << ", heightangle " << yangle_ << endl;

  camswitch_ = camswitch;
  camswindex_ = camswindex;
  if (!registered_)
  { vrmlscene_->hasCamera (this, objName->getString ());  // objName non nil
    registered_ = 1;
  }

  ge3dPushIdentity ();
  ge3dRotate (rotaxis_, - rotangle_);
  ge3d_translate (-pos_->x, -pos_->y, -pos_->z);
  ge3d_get_and_pop_matrix (mat_);

  ge3dMultMatrix ((const float (*)[4]) mat_);  // set up transformation (as in draw)
  // draw ();  // set up transformation

  copymatrix (mat_, invmat_);
  invertmatrix (invmat_);
} // QvPerspectiveCamera



/***** transformations *****/


// assert: point3D/vector3D compatible to float [3]
// (storing accumulated transformations would allow less push/pop calls
// but imply setting the transformation matrix on each primitive; had
// to flag wheter it changed; does not seem worthwile at the moment)


void QvTransform::build (QvState*)
{
  const vector3D* tran1 = (const vector3D*) translation.value;
  const vector3D* tran2 = (const vector3D*) center.value;
  const vector3D* rot1 = (const vector3D*) rotation.axis;
  const vector3D* rot2 = (const vector3D*) scaleOrientation.axis;
  const float angle1 = rotation.angle;  // rad
  const float angle2 = scaleOrientation.angle;
  const float* scale = scaleFactor.value;

  ge3dPushIdentity ();
  ge3d_translate (tran1->x + tran2->x, tran1->y + tran2->y, tran1->z + tran2->z);
  ge3dRotate (rot1, angle1);
  ge3dRotate (rot2, angle2);  // just rotates the scaling vector
  ge3dScale (scale);
  ge3dRotate (rot2, - angle2);
  ge3d_translate (-tran2->x, -tran2->y, -tran2->z);  // - tran2
  ge3d_get_and_pop_matrix (mat_);

  ge3dMultMatrix ((const float (*)[4]) mat_);  // set up transformation (as in draw)

  copymatrix (mat_, invmat_);
  invertmatrix (invmat_);

// cerr << "inverse transformation matrix: " << endl;
// for (int i = 0;  i < 4;  i++)
// printf ("%13f %12f %12f %12f\n", invmat_ [i][0], invmat_ [i][1], invmat_ [i][2], invmat_ [i][3]);

  copymatrix (invmat_, invtranspmat3D_);
  transposematrix (invtranspmat3D_);
  mat4Dto3D (invtranspmat3D_);  // cancel out last row and column

} // QvTransform


void QvRotation::build (QvState*)
{
  const vector3D* axis = (const vector3D*) rotation.axis;
  float angle = rotation.angle;  // rad

  ge3dPushIdentity ();
  ge3dRotate (axis, angle);  // set up transformation (as in draw)
  ge3d_get_and_pop_matrix (mat_);

  ge3dMultMatrix ((const float (*)[4]) mat_);  // set up transformation (as in draw)

  // rotations produce orthogonal matrices, so the inverse is simply
  // the transposed matrix; also they are always 3x3 essentially
  copymatrix (mat_, invmat_);
  transposematrix (invmat_);
}


void QvMatrixTransform::build (QvState*)
{
  mat_ = (const float (*)[4]) &matrix.value;
  ge3dMultMatrix (mat_);  // set up transformation (as in draw)

// fprintf (stderr, "matrix elements:\n"
//   "(%10g %10g %10g %10g)\n(%10g %10g %10g %10g)\n"
//   "(%10g %10g %10g %10g)\n(%10g %10g %10g %10g)\n",
//   mat_[0], mat_[1], mat_[2], mat_[3], mat_[4], mat_[5], mat_[6], mat_[7],
//   mat_[8], mat_[9], mat_[10], mat_[11], mat_[12], mat_[13], mat_[14], mat_[15]);

  copymatrix ((float (*)[4])mat_, invmat_);
  invertmatrix (invmat_);

  copymatrix (invmat_, invtranspmat3D_);
  transposematrix (invtranspmat3D_);
  mat4Dto3D (invtranspmat3D_);  // cancel out last row and column
}


void QvTranslation::build (QvState*)
{
  trans_ = (const vector3D*) translation.value;
  ge3dTranslate (trans_);  // set up transformation (as in draw)
}


void QvScale::build (QvState*)
{
  scale_ = scaleFactor.value;
  if (!scale_[0] || !scale_[1] || !scale_[2])
    QvDebugError::post ("Scale", "scaling factors must all be non-zero");

  invscale_[0] = (scale_[0] ? 1/scale_[0] : 1);
  invscale_[1] = (scale_[1] ? 1/scale_[1] : 1);
  invscale_[2] = (scale_[2] ? 1/scale_[2] : 1);

  ge3dScale (scale_);  // set up transformation (as in draw)
}



/***** shapes *****/


void QvAsciiText::build (QvState*)
{
// TODO
//vrmlscene_->increaseNumPrimitives ();
}


void QvCube::build (QvState*)
{
  // object coordinates
  omax_.x = width.value / 2.0;
  omax_.y = height.value / 2.0;
  omax_.z = depth.value / 2.0;
  omin_.x = -omax_.x;
  omin_.y = -omax_.y;
  omin_.z = -omax_.z;

  computeBoundingbox (omin_, omax_, wmin_, wmax_);  // applies current transformation
  hasextent_ = 1;

  vrmlscene_->increaseNumPrimitives ();
}


void QvCone::build (QvState*)
{
  int pts = parts.value;
  parts_ = 0;
  if (pts & QvCone::SIDES)
    parts_ |= cyl_sides;
  if (pts & QvCone::BOTTOM)
    parts_ |= cyl_bottom;
  // assert: ALL = SIDES | BOTTOM
  // note: QvLib defines enums SIDES/BOTTOM/[TOP] different for Cones and Cylinders

  if (!pts)  // no parts - no extent
    return;

  float r = bottomRadius.value;
  float h = height.value;

  omin_.x = omin_.z = -r;
  omax_.x = omax_.z = r;
  // possibly degenerated cone of bottom only
  if (pts == QvCone::BOTTOM)
    omin_.y = omax_.y = - h/2.0;
  else
    omin_.y = - (omax_.y = h/2.0);

  computeBoundingbox (omin_, omax_, wmin_, wmax_);  // applies current transformation
  hasextent_ = 1;

  vrmlscene_->increaseNumPrimitives ();
} // QvCone


void QvCylinder::build (QvState*)
{
  int pts = parts.value;
  parts_ = 0;
  if (pts & QvCylinder::SIDES)
    parts_ |= cyl_sides;
  if (pts & QvCylinder::TOP)
    parts_ |= cyl_top;
  if (pts & QvCylinder::BOTTOM)
    parts_ |= cyl_bottom;
  // assert: ALL = SIDES | TOP | BOTTOM

  if (!pts)  // no parts - no extent
    return;

  float r = radius.value;
  float h = height.value;

  omin_.x = omin_.z = -r;
  omax_.x = omax_.z = r;
  // possibly degenerated cylinder of bottom or top only
  if (pts == QvCylinder::TOP)
    omin_.y = omax_.y = h/2.0;
  else if (pts == QvCylinder::BOTTOM)
    omin_.y = omax_.y = - h/2.0;
  else
    omin_.y = - (omax_.y = h/2.0);

  computeBoundingbox (omin_, omax_, wmin_, wmax_);  // applies current transformation
  hasextent_ = 1;

  vrmlscene_->increaseNumPrimitives ();
} // QvCylinder


void QvSphere::build (QvState*)
{
  float r = radius.value;
  omin_.x = omin_.y = omin_.z = -r;
  omax_.x = omax_.y = omax_.z = r;

  computeBoundingbox (omin_, omax_, wmin_, wmax_);  // applies current transformation
  hasextent_ = 1;

  vrmlscene_->increaseNumPrimitives ();
} // QvSphere


void QvIndexedFaceSet::build (QvState* state)
{
//cerr << "QvIndexedFaceSet::build" << endl;
  QvElement* attr = state->getTopElement (QvState::Coordinate3Index);
  if (!attr)
  { cerr << "QvIndexedFaceSet. error: no vertices" << endl;
    numvertinds_ = nummatinds_ = numnormalinds_ = numtextureinds_ = 0;
    return;
  }

  QvCoordinate3* coords = (QvCoordinate3*) attr->data;
  omin_ = coords->omin_;
  omax_ = coords->omax_;
  computeBoundingbox (omin_, omax_, wmin_, wmax_);
  hasextent_ = 1;

  const QvMFVec3f& verts = coords->point;
  //cerr << "size of vertex coord list: " << verts.num << "; no. of coord indices: " << coordIndex.num << endl;

  // TODO: ensure that all indices are in proper range
  vertexlist_ = (const point3D*) verts.values;
  numvertinds_ = coordIndex.num;  // no. of vertex indices
  vertindices_ = (const int*) coordIndex.values;

  // find no. of faces
  unsigned numfaces = 0;
  unsigned nv = numvertinds_;
  const int* cind = vertindices_;
  if (nv && cind [nv-1] >= 0)  // incomplete last face
    numfaces = 1;
  while (nv--)
  { if (*cind++ < 0)
      numfaces++;
  }
  vrmlscene_->increaseNumFaces (numfaces);
  // should store this number to do no update when build is called
  // another time after fetching inline nodes

  // generate face normals
  // TODO: range check (poss. incomplete last face)
  if (!facenormals_ && numfaces)  // only once on multiple instances
  {
    facenormals_ = new vector3D [numfaces];
    vector3D* fn = facenormals_;
    nv = numvertinds_;
    cind = vertindices_;
    while (nv)
    {
      // here at the beginning of a new face
      int v0 = cind [0];
      int v1 = cind [1];
      int v2 = cind [2];
      // cerr << "computing face normal from indices " << v0 << ", " << v1 << ", " << v2 << ": ";
      if (v0 >= 0 && v1 >= 0 && v2 >= 0 && nv > 2)
      { // what to do on non CCW ordered faces?
        computeNormal (vertexlist_ [v0], vertexlist_ [v1], vertexlist_ [v2], *fn);
        // cerr << *fn << endl;
        float norm2 = dot3D (*fn, *fn);
        if (norm2 > 0.0)  // normalize
        { norm2 = 1 / sqrt (norm2);
          scl3D (*fn, norm2);
        }
        // cerr << *fn << endl;
      }
      else  // face with less than 3 vertices
        init3D (*fn, 0, 0, 0);

      // goto next face
      fn++;
      while (*cind >= 0 && nv)
        cind++, nv--;
      if (nv)  // skip index -1 (face separator)
        cind++, nv--;
    }
  } // face normals


  // material binding
  matbinding_ = matb_default;
  attr = state->getTopElement (QvState::MaterialBindingIndex);
  if (attr)
  { int matb = ((QvMaterialBinding*) attr->data)->value.value;
    if (matb >= 0 && matb <= QvMaterialBinding::PER_VERTEX_INDEXED)  // assert: max value
      matbinding_ = ge3dMatBindings [matb];
  }

  // materials
  attr = state->getTopElement (QvState::MaterialIndex);
  if (attr)
  {
    materials_ = &((QvMaterial*) attr->data)->materials_;
    nummatinds_ = materialIndex.num;  // no. of material indices
    matindices_ = (const int*) materialIndex.values;

    // Inventor spec: when _INDEXED material binding lacks material indices use coord indices instead
    if (matbinding_ == matb_pervertexindexed && nummatinds_ == 1 && *matindices_ == -1)
    {
      nummatinds_ = numvertinds_;
      matindices_ = vertindices_;
      // note: doing so only for *vertex* indexed,
      // as face/part indexed would use -1's as material index (TODO: filter them out)
    }
  }
  else
  { materials_ = 0;
    nummatinds_ = 0;
    matindices_ = 0;
  }


  // normal indices
  // TODO: automatic vertex normal generation (autosmooth)
  attr = state->getTopElement (QvState::NormalIndex);
  if (!attr)
  { // rarely entering here (default entry of -1)
    // normal indices useless without normals
    normallist_ = 0;
    numnormalinds_ = 0;
    normalindices_ = 0;
  }
  else
  {
    const QvMFVec3f& normals = ((QvNormal*) attr->data)->vector;
    //cerr << "size of normal vector list: " << normals.num << "; no. of normal indices: " << normalIndex.num << endl;

    // TODO: ensure that all indices are in proper range
    normallist_ = (const vector3D*) normals.values;
    numnormalinds_ = normalIndex.num;  // no. of normal indices
    normalindices_ = (const int*) normalIndex.values;

    // TODO: use coord indices on missing normal indices
    // on pervertexindexed normalbinding (Inventor spec)
  }

  // texture indices (no texture binding)
  // TODO: automatic texture coordinate generation (based on bounding box)
  attr = state->getTopElement (QvState::TextureCoordinate2Index);
  if (!attr)
  { // rarely entering here (default entry of -1)
    // texture indices useless without texture coordinates
    texvertlist_ = 0;
    numtextureinds_ = 0;
    textureindices_ = 0;
  }
  else
  {
    const QvMFVec2f& texverts = ((QvTextureCoordinate2*) attr->data)->point;
    //cerr << "size of tex.vert. list: " << texverts.num << "; no. of texture ind.: " << textureCoordIndex.num << endl;

    // TODO: ensure that all indices are in proper range
    texvertlist_ = (const point2D*) texverts.values;
    numtextureinds_ = textureCoordIndex.num;  // no. of texture indices
    textureindices_ = (const int*) textureCoordIndex.values;
  }

} // QvIndexedFaceSet



void QvIndexedLineSet::build (QvState* state)
{
//cerr << "QvIndexedLineSet::build" << endl;

  QvElement* attr = state->getTopElement (QvState::Coordinate3Index);
  if (!attr)
  { cerr << "QvIndexedLineSet. error: no vertices" << endl;
    numvertinds_ = 0;
    return;
  }

  epsilon_ = 0.05;  // picking tolerance

  QvCoordinate3* coords = (QvCoordinate3*) attr->data;
  omin_ = coords->omin_;
  omax_ = coords->omax_;
  // extend bounding box by epsilon
  vector3D delta;
  init3D (delta, epsilon_, epsilon_, epsilon_);
  inc3D (omax_, delta);  // omax_ += epsilon
  dec3D (omin_, delta);  // omin_ -= epsilon
  computeBoundingbox (omin_, omax_, wmin_, wmax_);
  hasextent_ = 1;
  //cerr << "world bounding box: " << wmin_ << wmax_ << endl;

  const QvMFVec3f& verts = coords->point;

  // TODO: ensure that all indices are in proper range
  // TODO: consider current material binding

//cerr << "number of points - size of vertex list: " << verts.num
//<< "; no. of coord indices: " << coordIndex.num << endl;

  vertexlist_ = (const point3D*) verts.values;
  numvertinds_ = coordIndex.num;  // no. of vertex indices
  vertindices_ = (const int*) coordIndex.values;

  // no normal and texture indices for lines

} // QvIndexedLineSet



void QvPointSet::build (QvState* state)
{
  QvElement* attr = state->getTopElement (QvState::Coordinate3Index);
  if (!attr)
  { cerr << "QvPointSet. error: no vertices" << endl;
    num_ = 0;
    return;
  }

  epsilon_ = 0.05;  // picking tolerance

  QvCoordinate3* coords = (QvCoordinate3*) attr->data;
  omin_ = coords->omin_;
  omax_ = coords->omax_;
  // extend bounding box by epsilon
  vector3D delta;
  init3D (delta, epsilon_, epsilon_, epsilon_);
  inc3D (omax_, delta);  // omax_ += epsilon
  dec3D (omin_, delta);  // omin_ -= epsilon
  computeBoundingbox (omin_, omax_, wmin_, wmax_);
  hasextent_ = 1;
  // cerr << "world bounding box: " << wmin_ << wmax_ << endl;

  const QvMFVec3f& verts = coords->point;

  points_ = (const point3D*) verts.values;
  int start = startIndex.value;
  num_ = numPoints.value;

  if (num_ < 0 || start + num_ > verts.num)  // use all remaining points
    num_ = verts.num - start;

  points_ += start;  // true beginning

// cerr << "QvPointSet::build: startIndex " << start
// << ", number: " << num_ << " (originally " << numPoints.value << ")" << endl;

} // QvPointSet



/***** WWW *****/


void QvWWWAnchor::build (QvState* state)
{
  // spec: WWWAnchor must behave like a separator (although it is not derived from it)
  state->push ();  // push attribute stacks
  ge3dPushIdentity ();

  if (!parentURL_.getLength ())
  { // such to handle relative anchors in inline scenes too
    parentURL_ = scene_->mostRecentURL ();
    DEBUGNL ("WWWAnchor relative to document [" << parentURL_.getString () << "].");
  }

  QvGroup::build (state);

  ge3d_pop_matrix ();
  state->pop ();  // pop stacks

  if (hasextent_)
    computeBoundingbox (omin_, omax_, wmin_, wmax_);  // applies current transformation

} // QvWWWAnchor


void QvWWWInline::build (QvState* state)
{
  // initially, WWWInline has no children - they get built when the link is fetched

  // bounding box
  const point3D* bsize = (const point3D*) bboxSize.value;
  const point3D* bcenter = (const point3D*) bboxCenter.value;

  if (state_ == s_virgin)
  { // such to handle nested relative inline scenes correctly
    parentURL_ = scene_->mostRecentURL ();
    DEBUGNL ("WWWInline for parent [" << parentURL_.getString () << "] encountered");
  }

  if (state_ == s_completed)  // children already read: use their bounding box
  {
    // cerr << "QvWWWInline::build: children already fetched. using their bounding box." << endl;
    hasextent_ = 0;  // possibly no geometry
    QvGroup::build (state);
  }
  else if (bsize->x > 0 || bsize->y > 0 || bsize->z > 0)  // nonempty BB specified
  {
    DEBUGNL ("WWWInline bounding box size: " << *bsize << ", center: " << *bcenter);

    // object coordinates
    pol3D (*bcenter, -0.5, *bsize, omin_);  // omin_ = bcenter - bsize/2
    add3D (omin_, *bsize, omax_);  // omax_ = min + bsize

    computeBoundingbox (omin_, omax_, wmin_, wmax_);
    hasextent_ = 1;
  }
  else
  { DEBUGNL ("QvWWWInline::build with empty bounding box");
  }

// cerr << "QvWWWInline::build. bounding box defined: " << hasextent_ << endl;
// if (hasextent_)
// cerr << "object boundings: " << min_ << ", " << max_ << ", world boundings: " << wmin_ << ", " << wmax_ << endl;

} // QvWWWInline



/***** misc *****/


void QvInfo::build (QvState*)
{
  const char* name = objName->getString ();  // objName non nil
  const char* info = string.value.getString ();

//cerr << "Info [" << name << "]: " << info << endl;

  if (!name || !*name)  // unnamed info
    return;

  if (!info || !*info)  // empty info
    return;

  if (!strcmp (name, BACKGROUND_INFO))
  {
    colorRGB col;
    if (sscanf (info, "%f %f %f", &col.R, &col.G, &col.B) == 3)
      ge3dBackgroundColor (&col);
    else
      QvDebugError::post ("Info", BACKGROUND_INFO " should be given as 3 floats, separated by spaces");
  }
  else if (!strcmp (name, VIEWER_INFO))
  { // just differ between flip ("examiner") and the other modes ("walk")

    if (!strcmp (info, "examiner"))
      scene_->navigationHint (Scene3D::nav_flip);
    else if (!strcmp (info, "walk"))
      scene_->navigationHint (Scene3D::nav_walk);
    else
      QvDebugError::post ("Info", VIEWER_INFO " should be defined as \"walk\" or \"examiner\"");
  } // VIEWER_INFO

} // QvInfo


void QvUnknownNode::build (QvState* state)  { QvGroup::build (state); }



/***** extensions *****/


void QvLabel::build (QvState*)
{
  if (newinstance_)
  { QvDebugError::post ("Label", "invalid VRML 1.0 node (ignored)\n"
      "        (further occurances will not be reported)");
    newinstance_ = 0;
  }
}


void QvLightModel::build (QvState*)
{
  if (newinstance_)
  { QvDebugError::post ("LightModel", "warning: extension to VRML 1.0 standard\n"
      "        (further occurances will not be reported)");
    newinstance_ = 0;
  }

  dolighting_ = model.value != QvLightModel::BASE_COLOR;
}