Q3CanvasPixmap Class Reference

#include <q3canvas.h>

Inheritance diagram for Q3CanvasPixmap:

[legend]Collaboration diagram for Q3CanvasPixmap:

[legend]List of all members.

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Detailed Description

The Q3CanvasPixmap class provides pixmaps for Q3CanvasSprites.

If you want to show a single pixmap on a Q3Canvas use a Q3CanvasSprite with just one pixmap.

When pixmaps are inserted into a Q3CanvasPixmapArray they are held as Q3CanvasPixmaps. {Q3CanvasSprite}s are used to show pixmaps on {Q3Canvas}es and hold their pixmaps in a Q3CanvasPixmapArray. If you retrieve a frame (pixmap) from a Q3CanvasSprite it will be returned as a Q3CanvasPixmap.

The pixmap is a QPixmap and can only be set in the constructor. There are three different constructors, one taking a QPixmap, one a QImage and one a file name that refers to a file in any supported file format (see QImageReader).

Q3CanvasPixmap can have a hotspot which is defined in terms of an (x, y) offset. When you create a Q3CanvasPixmap from a PNG file or from a QImage that has a QImage::offset(), the offset() is initialized appropriately, otherwise the constructor leaves it at (0, 0). You can set it later using setOffset(). When the Q3CanvasPixmap is used in a Q3CanvasSprite, the offset position is the point at Q3CanvasItem::x() and Q3CanvasItem::y(), not the top-left corner of the pixmap.

Note that for Q3CanvasPixmap objects created by a Q3CanvasSprite, the position of each Q3CanvasPixmap object is set so that the hotspot stays in the same position.

See also:

Q3CanvasPixmapArray Q3CanvasItem Q3CanvasSprite, QtCanvas, {Porting to Graphics View}

Definition at line 362 of file q3canvas.h.

Public Member Functions
	Q3CanvasPixmap (const QString &datafilename)
	Q3CanvasPixmap (const QImage &image)
	Q3CanvasPixmap (const QPixmap &, const QPoint &hotspot)
	~Q3CanvasPixmap ()
int	offsetX () const
int	offsetY () const
void	setOffset (int x, int y)
Private Member Functions
void	init (const QImage &)
void	init (const QPixmap &pixmap, int hx, int hy)
Private Attributes
int	hotx
int	hoty
QImage *	collision_mask
Friends
class	Q3CanvasSprite
class	Q3CanvasPixmapArray
bool	qt_testCollision (const Q3CanvasSprite *s1, const Q3CanvasSprite *s2)

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Constructor & Destructor Documentation

Q3CanvasPixmap::Q3CanvasPixmap

(

const QString &

datafilename

)

Constructs a Q3CanvasPixmap that uses the image stored in datafilename.

Definition at line 2687 of file q3canvas.cpp.

References image, and init().

{
    QImage image(datafilename);
    init(image);
}

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Q3CanvasPixmap::Q3CanvasPixmap

(

const QImage &

image

)

Constructs a Q3CanvasPixmap from the image image.

Definition at line 2698 of file q3canvas.cpp.

References image, and init().

{
    init(image);
}

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Q3CanvasPixmap::Q3CanvasPixmap	(	const QPixmap &	pm,
		const QPoint &	offset
	)

Constructs a Q3CanvasPixmap from the pixmap pm using the offset offset.

Definition at line 2706 of file q3canvas.cpp.

References init(), QPoint::x(), and QPoint::y().

{
    init(pm,offset.x(),offset.y());
}

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Q3CanvasPixmap::~Q3CanvasPixmap

(

)

Destroys the pixmap.

Definition at line 2740 of file q3canvas.cpp.

References collision_mask.

{
    delete collision_mask;
}

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Member Function Documentation

int Q3CanvasPixmap::offsetX

(

)

const [inline]

Returns the x-offset of the pixmap's hotspot.

See also:

setOffset()

Definition at line 372 of file q3canvas.h.

  { return hotx; }

int Q3CanvasPixmap::offsetY

(

)

const [inline]

Returns the y-offset of the pixmap's hotspot.

See also:

setOffset()

Definition at line 374 of file q3canvas.h.

  { return hoty; }

void Q3CanvasPixmap::setOffset	(	int	x,
		int	y
	)			[inline]

Sets the offset of the pixmap's hotspot to (x, y).

Warning:

Do not call this function if any Q3CanvasSprites are currently showing this pixmap.

Definition at line 376 of file q3canvas.h.

{ hotx = x; hoty = y; }

void Q3CanvasPixmap::init

(

const QImage &

)

[private]

Definition at line 2711 of file q3canvas.cpp.

References collision_mask, hotx, hoty, i, and image.

Referenced by Q3CanvasPixmap().

{
    convertFromImage(image);
    hotx = image.offset().x();
    hoty = image.offset().y();
#ifndef QT_NO_IMAGE_DITHER_TO_1
    if(image.hasAlphaBuffer()) {
  QImage i = image.createAlphaMask();
  collision_mask = new QImage(i);
    } else
#endif
  collision_mask = 0;
}

void Q3CanvasPixmap::init	(	const QPixmap &	pixmap,
		int	hx,
		int	hy
	)			[private]

Definition at line 2725 of file q3canvas.cpp.

References collision_mask, QPixmap::hasAlphaChannel(), hotx, hoty, i, and QPixmap::mask().

{
    (QPixmap&)*this = pixmap;
    hotx = hx;
    hoty = hy;
    if(pixmap.hasAlphaChannel())  {
  QImage i = mask().convertToImage();
  collision_mask = new QImage(i);
    } else
  collision_mask = 0;
}

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Friends And Related Function Documentation

friend class Q3CanvasSprite [friend]

Definition at line 384 of file q3canvas.h.

friend class Q3CanvasPixmapArray [friend]

Definition at line 385 of file q3canvas.h.

bool qt_testCollision	(	const Q3CanvasSprite *	s1,
		const Q3CanvasSprite *	s2
	)			[friend]

Definition at line 2171 of file q3canvas.cpp.

{
    const QImage* s2image = s2->imageAdvanced()->collision_mask;
    QRect s2area = s2->boundingRectAdvanced();

    QRect cyourarea(s2area.x(),s2area.y(),
      s2area.width(),s2area.height());

    QImage* s1image=s1->imageAdvanced()->collision_mask;

    QRect s1area = s1->boundingRectAdvanced();

    QRect ourarea = s1area.intersected(cyourarea);

    if (ourarea.isEmpty())
  return false;

    int x2=ourarea.x()-cyourarea.x();
    int y2=ourarea.y()-cyourarea.y();
    int x1=ourarea.x()-s1area.x();
    int y1=ourarea.y()-s1area.y();
    int w=ourarea.width();
    int h=ourarea.height();

    if (!s2image) {
  if (!s1image)
      return w>0 && h>0;
  // swap everything around
  int t;
  t=x1; x1=x2; x2=t;
  t=y1; x1=y2; y2=t;
  s2image = s1image;
  s1image = 0;
    }

    // s2image != 0

    // A non-linear search may be more efficient.
    // Perhaps spiralling out from the center, or a simpler
    // vertical expansion from the centreline.

    // We assume that sprite masks don't have
    // different bit orders.
    //
    // Q_ASSERT(s1image->bitOrder()==s2image->bitOrder());

    if (s1image) {
  if (s1image->bitOrder() == QImage::LittleEndian) {
      for (int j=0; j<h; j++) {
    uchar* ml = s1image->scanLine(y1+j);
    const uchar* yl = s2image->scanLine(y2+j);
    for (int i=0; i<w; i++) {
        if (*(yl + ((x2+i) >> 3)) & (1 << ((x2+i) & 7))
        && *(ml + ((x1+i) >> 3)) & (1 << ((x1+i) & 7)))
        {
      return true;
        }
    }
      }
  } else {
      for (int j=0; j<h; j++) {
    uchar* ml = s1image->scanLine(y1+j);
    const uchar* yl = s2image->scanLine(y2+j);
    for (int i=0; i<w; i++) {
        if (*(yl + ((x2+i) >> 3)) & (1 << (7-((x2+i) & 7)))
        && *(ml + ((x1+i) >> 3)) & (1 << (7-((x1+i) & 7))))
        {
      return true;
        }
    }
      }
  }
    } else {
  if (s2image->bitOrder() == QImage::LittleEndian) {
      for (int j=0; j<h; j++) {
    const uchar* yl = s2image->scanLine(y2+j);
    for (int i=0; i<w; i++) {
        if (*(yl + ((x2+i) >> 3)) & (1 << ((x2+i) & 7)))
        {
      return true;
        }
    }
      }
  } else {
      for (int j=0; j<h; j++) {
    const uchar* yl = s2image->scanLine(y2+j);
    for (int i=0; i<w; i++) {
        if (*(yl + ((x2+i) >> 3)) & (1 << (7-((x2+i) & 7))))
        {
      return true;
        }
    }
      }
  }
    }

    return false;
}

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Member Data Documentation

int Q3CanvasPixmap::hotx [private]

Definition at line 388 of file q3canvas.h.

Referenced by init(), and Q3CanvasSprite::leftEdge().

int Q3CanvasPixmap::hoty [private]

Definition at line 388 of file q3canvas.h.

Referenced by init(), and Q3CanvasSprite::topEdge().

QImage* Q3CanvasPixmap::collision_mask [private]

Definition at line 390 of file q3canvas.h.

Referenced by init(), Q3CanvasPixmapArray::readPixmaps(), and ~Q3CanvasPixmap().

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

• src/qt3support/canvas/q3canvas.h
• src/qt3support/canvas/q3canvas.cpp

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