text: /*
   This file is part of the VRender library.
   Copyright (C) 2005 Cyril Soler (Cyril.Soler@imag.fr)
   Version 1.0.0, released on June 27, 2005.
  
   http://artis.imag.fr/Members/Cyril.Soler/VRender
  
   VRender is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
  
   VRender is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
  
   You should have received a copy of the GNU General Public License
   along with VRender; if not, write to the Free Software Foundation, Inc.,
   51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
  */
  
  /****************************************************************************
  
   Copyright (C) 2002-2014 Gilles Debunne. All rights reserved.
  
   This file is part of the QGLViewer library version 2.7.1.
  
   http://www.libqglviewer.com - contact@libqglviewer.com
  
   This file may be used under the terms of the GNU General Public License 
   versions 2.0 or 3.0 as published by the Free Software Foundation and
   appearing in the LICENSE file included in the packaging of this file.
   In addition, as a special exception, Gilles Debunne gives you certain 
   additional rights, described in the file GPL_EXCEPTION in this package.
  
   libQGLViewer uses dual licensing. Commercial/proprietary software must
   purchase a libQGLViewer Commercial License.
  
   This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
   WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  
  *****************************************************************************/
  
  #include <stdio.h>
  #include "Primitive.h"
  #include "Exporter.h"
  #include "math.h"
  
  using namespace vrender ;
  using namespace std ;
  
  const double EPSExporter::EPS_GOURAUD_THRESHOLD = 0.05 ;
  const char *EPSExporter::CREATOR = "VRender library - (c) Cyril Soler 2005" ;
  
  float EPSExporter::last_r = -1.0 ;
  float EPSExporter::last_g = -1.0 ;
  float EPSExporter::last_b = -1.0 ;
  
  EPSExporter::EPSExporter()
  {
  	last_r = -1 ;
  	last_g = -1 ;
  	last_b = -1 ;
  }
  
  void EPSExporter::writeHeader(QTextStream& out) const
  {
  	/* Emit EPS header. */
  
  	out << "%!PS-Adobe-2.0 EPSF-2.0\n";
  
  	out << "%%%%HiResBoundingBox: " << _xmin << " " << _ymin << " " << _xmax << " " << _ymax << "\n";
  
  	out << "%%%%Creator: " << CREATOR << " (using OpenGL feedback)\n";
  	out << "%%EndComments\n\ngsave\n\n";
  
  	out << "%\n";
  	out << "% Contributors:\n";
  	out << "%\n";
  	out << "%   Frederic Delhoume (delhoume@ilog.fr):\n";
  	out << "%        Gouraud triangle PostScript fragment\n";
  	out << "%\n";
  	out << "%   Cyril Soler       (csoler@imag.fr):\n";
  	out << "%        BSP Sort,\n";
  	out << "%        Topological and advanced topological Sort,\n";
  	out << "%        Hidden surface removal,\n";
  	out << "%        Xfig3.2 (and EPS) format\n";
  	out << "%\n\n";
  
  	out << "/threshold " << EPS_GOURAUD_THRESHOLD << " def\n";
  
  	for(int i = 0; GOURAUD_TRIANGLE_EPS[i] != NULL; i++)
  		out << GOURAUD_TRIANGLE_EPS[i] << "\n";
  #ifdef A_VOIR
  	out <<  "\n" <<  << " setlinewidth\n\n", _lineWidth;
  #endif
  	/* Clear the background like OpenGL had it. */
  
  	if(_clearBG)
  	{
  		out << _clearR << " " << _clearG << " " << _clearB << " setrgbcolor\n";
  		out << _xmin << " " << _ymin << " " << _xmax << " " << _ymax << " rectfill\n\n";
  	}
  }
  
  void EPSExporter::writeFooter(QTextStream& out) const
  {
  	out << "grestore\n\n";
  
  	out << "% uncomment next line to be able to print to a printer.\n";
  	out << "% showpage\n";
  }
  
  void PSExporter::writeFooter(QTextStream& out) const
  {
  	out << "showpage\n";
  }
  
  const char *EPSExporter::GOURAUD_TRIANGLE_EPS[] =
  {
  	"/bd{bind def}bind def /triangle { aload pop   ",
  	"setrgbcolor aload pop 5 3 roll 4 2 roll 3 2 roll exch moveto lineto ",
  	"lineto closepath fill } bd /computediff1 { 2 copy sub abs threshold ",
  	"ge {pop pop pop true} { exch 2 index sub abs threshold ge { pop pop ",
  	"true} { sub abs threshold ge } ifelse } ifelse } bd /computediff3 { 3 ",
  	"copy 0 get 3 1 roll 0 get 3 1 roll 0 get computediff1 {true} { 3 copy ",
  	"1 get 3 1 roll 1 get 3 1 roll 1 get computediff1 {true} { 3 copy 2 ",
  	"get 3 1 roll  2 get 3 1 roll 2 get computediff1 } ifelse } ifelse } ",
  	"bd /middlecolor { aload pop 4 -1 roll aload pop 4 -1 roll add 2 div 5 ",
  	"1 roll 3 -1 roll add 2 div 3 1 roll add 2 div 3 1 roll exch 3 array ",
  	"astore } bd /gdt { computediff3 { 4 -1 roll aload 7 1 roll ",
  	"6 -1 roll pop 3 -1 roll pop add 2 div 3 1 roll add 2 div exch 3 -1 roll ",
  	"aload 7 1 roll exch pop 4 -1 roll pop add 2 div 3 1 roll add 2 div ",
  	"exch 3 -1 roll aload 7 1 roll pop 3 -1 roll pop add 2 div 3 1 roll add ",
  	"2 div exch 7 3 roll 10 -3 roll dup 3 index middlecolor 4 1 roll 2 copy ",
  	"middlecolor 4 1 roll 3 copy pop middlecolor 4 1 roll 13 -1 roll aload ",
  	"pop 17 index 6 index 15 index 19 index 6 index 17 index 6 array astore ",
  	"10 index 10 index 14 index gdt 17 index 5 index 17 index ",
  	"19 index 5 index 19 index 6 array astore 10 index 9 index 13 index ",
  	"gdt 13 index 16 index 5 index 15 index 18 index 5 index 6 ",
  	"array astore 12 index 12 index 9 index gdt 17 index 16 ",
  	"index 15 index 19 index 18 index 17 index 6 array astore 10 index 12 ",
  	"index 14 index gdt 18 {pop} repeat } { aload pop 5 3 roll ",
  	"aload pop 7 3 roll aload pop 9 3 roll 8 index 6 index 4 index add add 3 ",
  	"div 10 1 roll 7 index 5 index 3 index add add 3 div 10 1 roll 6 index 4 ",
  	"index 2 index add add 3 div 10 1 roll 9 {pop} repeat 3 array astore ",
  	"triangle } ifelse } bd",
  	NULL
  };
  
  void EPSExporter::spewPolygone(const Polygone *P, QTextStream& out)
  {
  	int nvertices;
  	GLfloat red, green, blue;
  	bool smooth;
  
  	nvertices = P->nbVertices() ;
  
      const Feedback3DColor& vertex = Feedback3DColor(P->sommet3DColor(0)) ;
  
  	if(nvertices > 0)
  	{
  		red   = vertex.red();
  		green = vertex.green();
  		blue  = vertex.blue();
  
  		smooth = false;
  
  		for(int i=1;i < nvertices && !smooth; i++)
  			if(fabs(red - P->sommet3DColor(i).red()) > 0.01 || fabs(green - P->sommet3DColor(i).green()) > 0.01 || fabs(blue - P->sommet3DColor(i).blue()) > 0.01)
  				smooth = true;
  
  		if(smooth && !_blackAndWhite)
  		{
  			/* Smooth shaded polygon; varying colors at vertices. */
  			/* Break polygon into "nvertices-2" triangle fans. */
  
  			for (int j = 0; j < nvertices - 2; j++)
  			{
  				out <<  "[" << P->sommet3DColor(0).x() << " " << P->sommet3DColor(j + 1).x() << " " << P->sommet3DColor(j + 2).x() 
  					<< " "	<< P->sommet3DColor(0).y() << " " << P->sommet3DColor(j + 1).y() << " " << P->sommet3DColor(j + 2).y() << "]";
  
  				out <<  " [" << P->sommet3DColor(0    ).red() << " " << P->sommet3DColor(0    ).green() << " " << P->sommet3DColor(0    ).blue() 
  					<< "] [" << P->sommet3DColor(j + 1).red() << " " << P->sommet3DColor(j + 1).green() << " " << P->sommet3DColor(j + 1).blue() 
  					<< "] [" << P->sommet3DColor(j + 2).red() << " " << P->sommet3DColor(j + 2).green() << " " << P->sommet3DColor(j + 2).blue() << "] gdt\n";
  
  				last_r = last_g = last_b = -1.0 ;
  			}
  		}
  		else
  		{
  			/* Flat shaded polygon and white polygons; all vertex colors the same. */
  
  			out <<  "newpath\n";
  
  			if(_blackAndWhite)
  				setColor(out,1.0,1.0,1.0) ;
  			else
  				setColor(out,red,green,blue) ;
  
  			/* Draw a filled triangle. */
  
  			out << P->sommet3DColor(0).x() << " " << P->sommet3DColor(0).y() << " moveto\n";
  
  			for (int i = 1; i < nvertices; i++)
  				out << P->sommet3DColor(i).x() << " " << P->sommet3DColor(i).y() << " lineto\n";
  
  			out << "closepath fill\n\n";
  		}
  	}
  }
  
  void EPSExporter::spewSegment(const Segment *S, QTextStream& out)
  {
    GLdouble dx, dy;
    GLfloat dr, dg, db, absR, absG, absB, colormax;
    int steps;
    GLdouble xstep=0.0, ystep=0.0;
    GLfloat rstep=0.0, gstep=0.0, bstep=0.0;
    GLdouble xnext=0.0, ynext=0.0, distance=0.0;
    GLfloat rnext=0.0, gnext=0.0, bnext=0.0;
  
    const Feedback3DColor& P1 = Feedback3DColor(S->sommet3DColor(0)) ;
    const Feedback3DColor& P2 = Feedback3DColor(S->sommet3DColor(1)) ;
  
    dr = P2.red()   - P1.red();
    dg = P2.green() - P1.green();
    db = P2.blue()  - P1.blue();
  
    if((!_blackAndWhite)&&(dr != 0 || dg != 0 || db != 0))
    {
  	  /* Smooth shaded line. */
  
  	  dx = P2.x() - P1.x();
  	  dy = P2.y() - P1.y();
  
  	  distance = sqrt(dx*dx + dy*dy);
  
  	  absR = fabs(dr);
  	  absG = fabs(dg);
  	  absB = fabs(db);
  
  	  colormax = max(absR, max(absG, absB));
  	  steps = int(0.5f + max(1.0, colormax * distance * EPS_SMOOTH_LINE_FACTOR));
  
  	  xstep = dx / steps;
  	  ystep = dy / steps;
  
  	  rstep = dr / steps;
  	  gstep = dg / steps;
  	  bstep = db / steps;
  
  	  xnext = P1.x();
  	  ynext = P1.y();
  	  rnext = P1.red();
  	  gnext = P1.green();
  	  bnext = P1.blue();
  
  	  /* Back up half a step; we want the end points to be
  		  exactly the their endpoint colors. */
  
  	  xnext -= xstep / 2.0;
  	  ynext -= ystep / 2.0;
  	  rnext -= rstep / 2.0f;
  	  gnext -= gstep / 2.0f;
  	  bnext -= bstep / 2.0f;
    }
    else
  	  steps = 0; /* Single color line. */
  
    if(_blackAndWhite)
  	  setColor(out,0.0,0.0,0.0) ;
    else
  	  setColor(out,P1.red(),P1.green(),P1.blue()) ;
  
    out << P1.x() << " " << P1.y() << " moveto\n";
  
    for(int i = 0;i < steps;i++)
    {
  	  xnext += xstep;
  	  ynext += ystep;
  	  rnext += rstep;
  	  gnext += gstep;
  	  bnext += bstep;
  
  	  out << xnext << " " << ynext << " lineto stroke\n";
  	  out << rnext << " " << gnext << " " << bnext << " setrgbcolor\n";
  	  out << xnext << " " << ynext << " moveto\n";
  
  	  last_r = last_g = last_b = -1.0 ;
    }
    out << P2.x() << " " << P2.y() << " lineto stroke\n";
  }
  
  void EPSExporter::spewPoint(const Point *P, QTextStream& out)
  {
  	const Feedback3DColor& p = Feedback3DColor(P->sommet3DColor(0)) ;
  
  	if(_blackAndWhite)
  		setColor(out,0.0,0.0,0.0) ;
  	else
  		setColor(out,p.red(),p.green(),p.blue()) ;
  
  	out << p.x() << " " << p.y() << " " << (_pointSize / 2.0) << " 0 360 arc fill\n\n";
  }
  
  void EPSExporter::setColor(QTextStream& out, float red, float green, float blue)
  {
  	if(last_r != red || last_g != green || last_b != blue)
  		out << red << " " << green << " " << blue << " setrgbcolor\n";
  
  	last_r = red ;
  	last_g = green ;
  	last_b = blue ;
  }
  
  