impeller::SkylineRectanglePacker Class Reference

Inheritance diagram for impeller::SkylineRectanglePacker:

Public Member Functions
	SkylineRectanglePacker (int w, int h)
	~SkylineRectanglePacker () final
void	Reset () final
	Empty out all previously added rectangles. More...
bool	AddRect (int w, int h, IPoint16 *loc) final
	Attempt to add a rect without moving already placed rectangles. More...
Scalar	PercentFull () const final
	Returns how much area has been filled with rectangles. More...
Public Member Functions inherited from impeller::RectanglePacker
virtual	~RectanglePacker ()
virtual bool	AddRect (int width, int height, IPoint16 *loc)=0
	Attempt to add a rect without moving already placed rectangles. More...
virtual Scalar	PercentFull () const =0
	Returns how much area has been filled with rectangles. More...
virtual void	Reset ()=0
	Empty out all previously added rectangles. More...

Additional Inherited Members
Static Public Member Functions inherited from impeller::RectanglePacker
static std::shared_ptr< RectanglePacker >	Factory (int width, int height)
	Return an empty packer with area specified by width and height. More...
Protected Member Functions inherited from impeller::RectanglePacker
	RectanglePacker (int width, int height)
int	width () const
int	height () const

Detailed Description

Definition at line 18 of file rectangle_packer.cc.

Constructor & Destructor Documentation

SkylineRectanglePacker()

impeller::SkylineRectanglePacker::SkylineRectanglePacker ( int  w, int  h  )

inline

Definition at line 20 of file rectangle_packer.cc.

: RectanglePacker(w, h) { Reset(); }

~SkylineRectanglePacker()

impeller::SkylineRectanglePacker::~SkylineRectanglePacker ( )

inlinefinal

Definition at line 22 of file rectangle_packer.cc.

{}

Member Function Documentation

AddRect()

bool impeller::SkylineRectanglePacker::AddRect ( int  width, int  height, IPoint16 *  loc  )

finalvirtual

Attempt to add a rect without moving already placed rectangles.

Parameters

[in]	width	The width of the rectangle to add.
[in]	height	The height of the rectangle to add.
[out]	loc	If successful, will be set to the position of the upper-left corner of the rectangle.

Returns

Return true on success; false on failure.

Implements impeller::RectanglePacker.

Definition at line 61 of file rectangle_packer.cc.

                                                                             {
  if ((unsigned)p_width > (unsigned)width() ||
      (unsigned)p_height > (unsigned)height()) {
    return false;
  }
 
  // find position for new rectangle
  int bestWidth = width() + 1;
  int bestX = 0;
  int bestY = height() + 1;
  int bestIndex = -1;
  for (auto i = 0u; i < skyline_.size(); ++i) {
    int y;
    if (RectangleFits(i, p_width, p_height, &y)) {
      // minimize y position first, then width of skyline
      if (y < bestY || (y == bestY && skyline_[i].width_ < bestWidth)) {
        bestIndex = i;
        bestWidth = skyline_[i].width_;
        bestX = skyline_[i].x_;
        bestY = y;
      }
    }
  }
 
  // add rectangle to skyline
  if (-1 != bestIndex) {
    AddSkylineLevel(bestIndex, bestX, bestY, p_width, p_height);
    loc->x_ = bestX;
    loc->y_ = bestY;
 
    area_so_far_ += p_width * p_height;
    return true;
  }
 
  loc->x_ = 0;
  loc->y_ = 0;
  return false;
}

PercentFull()

Scalar impeller::SkylineRectanglePacker::PercentFull ( ) const

inlinefinalvirtual

Returns how much area has been filled with rectangles.

Returns

Percentage as a decimal between 0.0 and 1.0

Implements impeller::RectanglePacker.

Definition at line 32 of file rectangle_packer.cc.

                                   {
    return area_so_far_ / ((float)width() * height());
  }

Reset()

void impeller::SkylineRectanglePacker::Reset ( )

inlinefinalvirtual

Empty out all previously added rectangles.

Implements impeller::RectanglePacker.

Definition at line 24 of file rectangle_packer.cc.

                     {
    area_so_far_ = 0;
    skyline_.clear();
    skyline_.push_back(SkylineSegment{0, 0, width()});
  }

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The documentation for this class was generated from the following file:

• impeller/typographer/rectangle_packer.cc