/**************************************************************************\
 *
 *  This file is part of the Coin 3D visualization library.
 *  Copyright (C) 1998-2007 by Systems in Motion.  All rights reserved.
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  ("GPL") version 2 as published by the Free Software Foundation.
 *  See the file LICENSE.GPL at the root directory of this source
 *  distribution for additional information about the GNU GPL.
 *
 *  For using Coin with software that can not be combined with the GNU
 *  GPL, and for taking advantage of the additional benefits of our
 *  support services, please contact Systems in Motion about acquiring
 *  a Coin Professional Edition License.
 *
 *  See http://www.coin3d.org/ for more information.
 *
 *  Systems in Motion, Postboks 1283, Pirsenteret, 7462 Trondheim, NORWAY.
 *  http://www.sim.no/  sales@sim.no  coin-support@coin3d.org
 *
\**************************************************************************/

( const SoGLCoordinateElement * coords,
    const SbVec3f *normals,
    SoMaterialBundle * mb,
    const SoTextureCoordinateBundle * tb,
    SbBool needNormals,
    int rowsize,
    int colsize,
    int start )
{
  assert(rowsize >= 0 && colsize >= 0 && start >= 0);
  assert(coords->getNum() - start >= rowsize * colsize);

  const SbVec3f * coords3d = NULL;
  const SbVec4f * coords4d = NULL;
  const SbBool is3d = coords->is3D();
  if (is3d) {
    coords3d = coords->getArrayPtr3();
  }
  else {
    coords4d = coords->getArrayPtr4();
  }

  // This is the same code as in SoGLCoordinateElement::send().
  // It is inlined here for speed (~15% speed increase).
#define SEND_VERTEX(_idx_) \
  if (is3d) glVertex3fv((const GLfloat*) (coords3d + (_idx_))); \
  else glVertex4fv((const GLfloat*) (coords4d + (_idx_)));

#if MBINDING==PER_FACE || MBINDING==PER_ROW
  int midx = 0;
#endif
  SbVec3f dummynormal(0.0f, 0.0f, 1.0f);
  const SbVec3f * currnormal = &dummynormal;
  if (normals) currnormal = normals;

#if NBINDING==OVERALL
  if (needNormals) {
    glNormal3fv((const GLfloat *)currnormal);
  }
#endif
  int curridx; // for optimization only

  for (int i = 0; i < colsize-1; i++) {
    int j = 0;
    glBegin(GL_QUAD_STRIP);
#if NBINDING==PER_ROW
    currnormal = normals++;
    glNormal3fv((const GLfloat *)currnormal);
#endif
#if MBINDING==PER_ROW
    mb->send(midx++,TRUE);
#endif

    for (j = 0; j < rowsize; j++) {
      curridx = IDX(i,j);
#if NBINDING==PER_VERTEX
      currnormal = &normals[curridx];
      glNormal3fv((const GLfloat *)currnormal);
#endif
#if NBINDING==PER_FACE
      currnormal = normals++;
      glNormal3fv((const GLfloat *)currnormal);
#endif
#if MBINDING==PER_VERTEX
      mb->send(curridx, TRUE);
#endif

#if TEXTURES==TRUE
      tb->send(curridx, coords->get3(start + curridx),
               *currnormal);
#endif
      SEND_VERTEX(start + curridx);
      curridx = IDX(i+1,j);
#if NBINDING==PER_VERTEX
      currnormal = &normals[curridx];
      glNormal3fv((const GLfloat *)currnormal);
#endif
#if MBINDING==PER_VERTEX
      mb->send(curridx, TRUE);
#endif
#if TEXTURES==TRUE
      tb->send(curridx, coords->get3(start + curridx), *currnormal);
#endif
#if MBINDING==PER_FACE
      // FIXME: optimize by moving first 2 vertices in row outside loop
      if (j > 0) mb->send(midx++, TRUE);
#endif
      SEND_VERTEX(start + curridx);
    }
    glEnd(); // end of strip/row
  }
}