kc3-lang/ftgl/src/FTVectoriser.cpp

Branch : - branch - master - tag -

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  Commit

• Author : henry
  Date : 2001-08-05 22:28:29
  Hash : a1ed83ae
  Message : const rampage:) added next2 to curve code

• src/FTVectoriser.cpp

• #include	"FTVectoriser.h"
  #include	"FTGL.h"
  
  
  FTContour::FTContour()
  {	
  	pointList.reserve( 1000); // FIXME magic number
  }
  
  
  FTContour::~FTContour()
  {
  	pointList.clear();
  }
  
  
  void FTContour::AddPoint( const int x, const int y)
  {
  	ftPoint point( static_cast<float>( x), static_cast<float>( y), 0.0); 
  	
  	// Eliminate duplicate points.
  	if( ( pointList[pointList.size() - 1] != point) && pointList[0] != point)
  	{
  		pointList.push_back( point);
  	}
  }
  
  
  // De Casteljau algorithm supplied by Jed Soane
  void FTVectoriser::deCasteljau( const float t, const int n)
  {
      //Calculating successive b(i)'s using de Casteljau algorithm.
      for( int i = 1; i <= n; i++)
          for( int k = 0; k <= (n - i); k++)
          {
  			bValues[i][k][0] = (1 - t) * bValues[i - 1][k][0] + t * bValues[i - 1][k + 1][0];
  			bValues[i][k][1] = (1 - t) * bValues[i - 1][k][1] + t * bValues[i - 1][k + 1][1];
  		}
  		
      //Specify next vertex to be included on curve
  	contour->AddPoint( bValues[n][0][0], bValues[n][0][1]);
  }
  
  
  // De Casteljau algorithm supplied by Jed Soane
  void FTVectoriser::evaluateCurve( const int n)
  {
      // setting the b(0) equal to the control points
      for( int i = 0; i <= n; i++)
  	{
  		bValues[0][i][0] = ctrlPtArray[i][0];
  		bValues[0][i][1] = ctrlPtArray[i][1];
      } //end for(i..)
  
      float t;            					//parameter for curve point calc. [0.0, 1.0]
      const float stepSize = 0.2; // FIXME variable
  
      for( int m = 0; m <= (1 / stepSize); m++)
      {
      	t = m * stepSize;
          deCasteljau( t, n);  //calls to evaluate point on curve att.
      } //end for(m...)
  }
  
  
  FTVectoriser::FTVectoriser( const FT_Glyph glyph)
  :	contourFlag(0),
  	contour(0)
  {
  	FT_OutlineGlyph outline = (FT_OutlineGlyph)glyph;
  	ftOutline = outline->outline;
  	
  	contourList.reserve( ftOutline.n_contours);
  }
  
  
  FTVectoriser::~FTVectoriser()
  {
  	for( int c = 0; c < contours(); ++c)
  	{
  		delete contourList[c];
  	}
  
  	contourList.clear();
  }
  
  
  int FTVectoriser::points()
  {
  	int s = 0;
  	for( int c = 0; c < contours(); ++c)
  	{
  		s += contourList[c]->size();
  	}
  	
  	return s;
  }
  
  
  bool FTVectoriser::Ingest()
  {
      if ( ( ftOutline.n_contours < 1) || ( ftOutline.n_points < 3)) //FIXME check this
  		return false;
  
  	short first = 0;
  	short last;
  	const short cont = ftOutline.n_contours;
  	
  	for( short c = 0; c < cont; ++c)
  	{
  		contour = new FTContour;
  		contourFlag = ftOutline.flags;
  		last = ftOutline.contours[c];
  
  		for( short p = first; p <= last; ++p)
  		{
  			switch( ftOutline.tags[p])
  			{
  				case FT_Curve_Tag_Conic:
  					p += Conic( p, first, last);
  					break;
  				case FT_Curve_Tag_Cubic:
  					p += Cubic( p, first, last);
  					break;
  				case FT_Curve_Tag_On:
  				default:
   					contour->AddPoint( ftOutline.points[p].x, ftOutline.points[p].y);
  			}
  		}
  		
  		contourList.push_back( contour);
  		first = last + 1;
  	}
  	
  	return true;
  }
  
  
  int FTVectoriser::Conic( const int index, const int first, const int last)
  {
  	int next = index + 1;
  	int prev = index - 1;
  	
  	if( index == last)
  		next = first; 
  	
  	if( index == first)
  		prev = last; 
  	
  	if( ftOutline.tags[next] != FT_Curve_Tag_Conic)
  	{
  		ctrlPtArray[0][0] = ftOutline.points[prev].x;	ctrlPtArray[0][1] = ftOutline.points[prev].y;
  		ctrlPtArray[1][0] = ftOutline.points[index].x;	ctrlPtArray[1][1] = ftOutline.points[index].y;
  		ctrlPtArray[2][0] = ftOutline.points[next].x;	ctrlPtArray[2][1] = ftOutline.points[next].y;
  		
  		evaluateCurve( 2);
  		return 1;
  	}
  	else
  	{
  		int next2 = next + 1;
  		if( next == last)
  			next2 = first;
  		
  		//create a phantom point
  		float x = ( ftOutline.points[index].x + ftOutline.points[next].x) / 2;
  		float y = ( ftOutline.points[index].y + ftOutline.points[next].y) / 2;
  		
  		// process first curve
  		ctrlPtArray[0][0] = ftOutline.points[prev].x;	ctrlPtArray[0][1] = ftOutline.points[prev].y;
  		ctrlPtArray[1][0] = ftOutline.points[index].x;	ctrlPtArray[1][1] = ftOutline.points[index].y;
  		ctrlPtArray[2][0] = x;							ctrlPtArray[2][1] = y;
  		
  		evaluateCurve( 2);
  		
  		// process second curve
  		ctrlPtArray[0][0] = x;							ctrlPtArray[0][1] = y;
  		ctrlPtArray[1][0] = ftOutline.points[next].x;	ctrlPtArray[1][1] = ftOutline.points[next].y;
  		ctrlPtArray[2][0] = ftOutline.points[next2].x;	ctrlPtArray[2][1] = ftOutline.points[next2].y;
  		evaluateCurve( 2);
  		
  		return 2;
  	}
  }
  
  
  int FTVectoriser::Cubic( const int index, const int first, const int last)
  {
  	int next = index + 1;
  	int prev = index - 1;
  	
  	if( index == last)
  		next = first; 
  	
  	int next2 = next + 1;
  	
  	if( next == last)
  		next2 = first;
  	
  	if( index == first)
  		prev = last; 
  
  	ctrlPtArray[0][0] = ftOutline.points[prev].x;		ctrlPtArray[0][1] = ftOutline.points[prev].y;
  	ctrlPtArray[1][0] = ftOutline.points[index].x;		ctrlPtArray[1][1] = ftOutline.points[index].y;
  	ctrlPtArray[2][0] = ftOutline.points[next].x;		ctrlPtArray[2][1] = ftOutline.points[next].y;
  	ctrlPtArray[3][0] = ftOutline.points[next2].x;		ctrlPtArray[3][1] = ftOutline.points[next2].y;
  
  	evaluateCurve( 3);
  	return 2;
  }
  
  
  void FTVectoriser::Output( double* data)
  {
  	int i = 0;
  	
  	for( int c= 0; c < contours(); ++c)
  	{
  		const FTContour* contour = contourList[c];
  		
  		for( int p = 0; p < contour->size(); ++p)
  		{
  			data[i] = static_cast<double>(contour->pointList[p].x / 64.0f); // is 64 correct?
  			data[i + 1] = static_cast<double>(contour->pointList[p].y / 64.0f);
  			data[i + 2] = 0.0; // static_cast<double>(contour->pointList[p].z / 64.0f);
  			i += 3;
  		}
  	}
  }