libcrbn/rendering/scanline.hpp

#ifndef __scanliner_hpp__
#define __scanliner_hpp__

#include <deque>

#include <crbn/basic/vec3.hpp>

class Scanline
{
public:
  Scanline( int w, int h ) {
    _array = new vec3 [ w ];
    _remaining = w;
    _height = h;
  }
  ~Scanline() {
    delete [] _array;
    _array = 0;
  }
  int height() { return _height; }
  bool filled() { return (_remaining == 0); }

  void put( int x, vec3& col ) {
    _array[ x ] = col;
    --_remaining;
  }

  vec3* get() {
    return _array;
  }
private:
  vec3* _array;
  int _remaining;
  int _height;
};

typedef std::deque<Scanline*> scanlineq;

class Scanliner
{
public:
  // CTOR
  Scanliner( int w, int h ) {
    _scanlines.clear();
    _scanlines.push_back( new Scanline( w, 0 ) );
    _w = w;
    _h = h;
  }
  //DTOR
  ~Scanliner() {
    for( unsigned i = 0; i < _scanlines.size(); ++i ) {
      delete _scanlines[ i ];
    }
    _scanlines.clear();
  }

  // Add a color in the stuff
  void put( int x, int y, vec3& col ) {
    Scanline* scanline = 0;
    if( _scanlines.empty() ) {
      scanline = new Scanline( _w, y );
      scanline -> put( x, col );
      _scanlines.push_back( scanline );
    } else {
      unsigned decal = y - _scanlines[ 0 ] -> height();
      if( decal >= _scanlines.size() ) {
        scanline = new Scanline( _w, y );
        scanline -> put( x, col );
        _scanlines.push_back( scanline );
      } else {
        _scanlines[ decal ] -> put( x, col );
      }
    }
  }

  // Gets the first scanline if it's filled
  vec3* get() {
    if( _scanlines.empty() )
      return 0;
    if( !( _scanlines[ 0 ] -> filled()) )
      return 0;
    return _scanlines[ 0 ] -> get();
  }

  // remove the first scanline in queue
  void clear_first() {
    if( !_scanlines.empty() ) {
      delete _scanlines[ 0 ];
      _scanlines.pop_front();
    }
  }
private:
  int _w, _h;
  scanlineq _scanlines;
};

#endif // __scanliner_hpp__

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