q3canvas.cpp

奇趣公司比较新的qt/emd版本

\internal
This method removes the view \a view from the list of Q3CanvasView objects
viewing this Q3Canvas. The Q3CanvasView class calls this.
*/
void Q3Canvas::removeView(Q3CanvasView* view)
{
    d->viewList.removeRef(view);
}

/*!
    Sets the canvas to call advance() every \a ms milliseconds. Any
    previous setting by setAdvancePeriod() or setUpdatePeriod() is
    overridden.

    If \a ms is less than 0 advancing will be stopped.
*/
void Q3Canvas::setAdvancePeriod(int ms)
{
    if (ms<0) {
	if (update_timer)
	    update_timer->stop();
    } else {
	if (update_timer)
	    delete update_timer;
	update_timer = new QTimer(this);
	connect(update_timer,SIGNAL(timeout()),this,SLOT(advance()));
	update_timer->start(ms);
    }
}

/*!
    Sets the canvas to call update() every \a ms milliseconds. Any
    previous setting by setAdvancePeriod() or setUpdatePeriod() is
    overridden.

    If \a ms is less than 0 automatic updating will be stopped.
*/
void Q3Canvas::setUpdatePeriod(int ms)
{
    if (ms<0) {
	if (update_timer)
	    update_timer->stop();
    } else {
	if (update_timer)
	    delete update_timer;
	update_timer = new QTimer(this);
	connect(update_timer,SIGNAL(timeout()),this,SLOT(update()));
	update_timer->start(ms);
    }
}

/*!
    Moves all Q3CanvasItem::animated() canvas items on the canvas and
    refreshes all changes to all views of the canvas. (An `animated'
    item is an item that is in motion; see setVelocity().)

    The advance takes place in two phases. In phase 0, the
    Q3CanvasItem::advance() function of each Q3CanvasItem::animated()
    canvas item is called with paramater 0. Then all these canvas
    items are called again, with parameter 1. In phase 0, the canvas
    items should not change position, merely examine other items on
    the canvas for which special processing is required, such as
    collisions between items. In phase 1, all canvas items should
    change positions, ignoring any other items on the canvas. This
    two-phase approach allows for considerations of "fairness",
    although no Q3CanvasItem subclasses supplied with Qt do anything
    interesting in phase 0.

    The canvas can be configured to call this function periodically
    with setAdvancePeriod().

    \sa update()
*/
void Q3Canvas::advance()
{
    Q3PtrDictIterator<void> it=d->animDict;
    while (it.current()) {
	Q3CanvasItem* i = (Q3CanvasItem*)(void*)it.currentKey();
	++it;
	if (i)
	    i->advance(0);
    }
    // we expect the dict contains the exact same items as in the
    // first pass.
    it.toFirst();
    while (it.current()) {
	Q3CanvasItem* i = (Q3CanvasItem*)(void*)it.currentKey();
	++it;
	if (i)
	    i->advance(1);
    }
    update();
}

// Don't call this unless you know what you're doing.
// p is in the content's co-ordinate example.
/*!
  \internal
*/
void Q3Canvas::drawViewArea(Q3CanvasView* view, QPainter* p, const QRect& vr, bool)
{
    QPoint tl = view->contentsToViewport(QPoint(0,0));

#ifndef QT_NO_TRANSFORMATIONS
    QMatrix wm = view->worldMatrix();
    QMatrix iwm = wm.invert();
    // ivr = covers all chunks in vr
    QRect ivr = iwm.map(vr);
    QMatrix twm;
    twm.translate(tl.x(),tl.y());
#else
    QRect ivr = vr;
#endif

    QRect all(0,0,width(),height());

    if (!all.contains(ivr)) {
	// Need to clip with edge of canvas.

#ifndef QT_NO_TRANSFORMATIONS
	// For translation-only transformation, it is safe to include the right
	// and bottom edges, but otherwise, these must be excluded since they
	// are not precisely defined (different bresenham paths).
	Q3PointArray a;
	if (wm.m12()==0.0 && wm.m21()==0.0 && wm.m11() == 1.0 && wm.m22() == 1.0)
	    a = Q3PointArray(QRect(all.x(),all.y(),all.width()+1,all.height()+1));
	else
	    a = Q3PointArray(all);

	a = (wm*twm).map(a);
#else
	Q3PointArray a(QRect(all.x(),all.y(),all.width()+1,all.height()+1));
#endif
	if (view->viewport()->backgroundMode() == NoBackground) {
	    QRect cvr = vr; cvr.moveBy(tl.x(),tl.y());
	    qt_setclipregion(p, QRegion(cvr)-QRegion(a));
	    p->fillRect(vr,view->viewport()->palette()
                        .brush(QPalette::Active,QPalette::Window));
	}
	qt_setclipregion(p, a);
    }

    QRect r = vr; r.moveBy(tl.x(),tl.y()); // move to untransformed co-ords
    if (!all.contains(ivr)) {
        QRegion inside = p->clipRegion() & r;
        //QRegion outside = p->clipRegion() - r;
        //p->setClipRegion(outside);
        //p->fillRect(outside.boundingRect(),red);
        qt_setclipregion(p, inside);
    } else {
        qt_setcliprect(p, r);
    }
#ifndef QT_NO_TRANSFORMATIONS
    p->setWorldMatrix(wm*twm);
#else
#endif
    drawCanvasArea(ivr,p,false);
}

/*!
    Repaints changed areas in all views of the canvas.

    \sa advance()
*/
void Q3Canvas::update()
{
    // ##### fix QT_NO_TRANSFORMATIONS
#ifndef QT_NO_TRANSFORMATIONS
    Q3PtrList<QRect> doneareas;
    doneareas.setAutoDelete(true);
#endif

    Q3PtrListIterator<Q3CanvasView> it(d->viewList);
    Q3CanvasView* view;
    while((view=it.current()) != 0) {
	++it;
#ifndef QT_NO_TRANSFORMATIONS
	QMatrix wm = view->worldMatrix();
#endif
	QRect area(view->contentsX(),view->contentsY(),
		   view->visibleWidth(),view->visibleHeight());
	if (area.width()>0 && area.height()>0) {
#ifndef QT_NO_TRANSFORMATIONS
            // r = Visible area of the canvas where there are changes
            QRect r = changeBounds(view->inverseWorldMatrix().map(area));
            if (!r.isEmpty()) {
                QRect tr = wm.map(r);
                tr.moveBy(-view->contentsX(), -view->contentsY());
                view->viewport()->update(tr);
                doneareas.append(new QRect(r));
            }
#endif
	}
    }

#ifndef QT_NO_TRANSFORMATIONS
    for (QRect* r=doneareas.first(); r != 0; r=doneareas.next())
	setUnchanged(*r);
#endif
}


/*!
    Marks the whole canvas as changed.
    All views of the canvas will be entirely redrawn when
    update() is called next.
*/
void Q3Canvas::setAllChanged()
{
    setChanged(QRect(0,0,width(),height()));
}

/*!
    Marks \a area as changed. This \a area will be redrawn in all
    views that are showing it when update() is called next.
*/
void Q3Canvas::setChanged(const QRect& area)
{
    QRect thearea = area.intersected(QRect(0, 0, width(), height()));

    int mx = (thearea.x()+thearea.width()+chunksize)/chunksize;
    int my = (thearea.y()+thearea.height()+chunksize)/chunksize;
    if (mx>chwidth)
	mx=chwidth;
    if (my>chheight)
	my=chheight;

    int x=thearea.x()/chunksize;
    while(x<mx) {
	int y = thearea.y()/chunksize;
	while(y<my) {
	    chunk(x,y).change();
	    y++;
	}
	x++;
    }
}

/*!
    Marks \a area as \e unchanged. The area will \e not be redrawn in
    the views for the next update(), unless it is marked or changed
    again before the next call to update().
*/
void Q3Canvas::setUnchanged(const QRect& area)
{
    QRect thearea = area.intersected(QRect(0, 0, width(), height()));

    int mx = (thearea.x()+thearea.width()+chunksize)/chunksize;
    int my = (thearea.y()+thearea.height()+chunksize)/chunksize;
    if (mx>chwidth)
	mx=chwidth;
    if (my>chheight)
	my=chheight;

    int x=thearea.x()/chunksize;
    while(x<mx) {
	int y = thearea.y()/chunksize;
	while(y<my) {
	    chunk(x,y).takeChange();
	    y++;
	}
	x++;
    }
}


/*!
  \internal
*/
QRect Q3Canvas::changeBounds(const QRect& inarea)
{
    QRect area = inarea.intersected(QRect(0, 0, width(), height()));

    int mx = (area.x()+area.width()+chunksize)/chunksize;
    int my = (area.y()+area.height()+chunksize)/chunksize;
    if (mx > chwidth)
	mx=chwidth;
    if (my > chheight)
	my=chheight;

    QRect result;

    int x=area.x()/chunksize;
    while(x<mx) {
	int y=area.y()/chunksize;
	while(y<my) {
	    Q3CanvasChunk& ch=chunk(x,y);
	    if (ch.hasChanged())
		result |= QRect(x,y,1,1);
	    y++;
	}
	x++;
    }

    if (!result.isEmpty()) {
	result.rLeft() *= chunksize;
	result.rTop() *= chunksize;
	result.rRight() *= chunksize;
	result.rBottom() *= chunksize;
	result.rRight() += chunksize;
	result.rBottom() += chunksize;
    }

    return result;
}

void Q3Canvas::ensureOffScrSize(int osw, int osh)
{
    if (osw > offscr.width() || osh > offscr.height())
	offscr.resize(QMAX(osw,offscr.width()),
		      QMAX(osh,offscr.height()));
    else if (offscr.width() == 0 || offscr.height() == 0)
	offscr.resize(QMAX(offscr.width(), 1),
		       QMAX(offscr.height(), 1));
}

/*!
    Paints all canvas items that are in the area \a clip to \a
    painter, using double-buffering if \a dbuf is true.

    e.g. to print the canvas to a printer:
    \code
    QPrinter pr;
    if (pr.setup()) {
	QPainter p(&pr);
	canvas.drawArea(canvas.rect(), &p);
    }
    \endcode
*/
void Q3Canvas::drawArea(const QRect& clip, QPainter* painter, bool dbuf)
{
    if (painter)
	drawCanvasArea(clip, painter, dbuf);
}

#include <qdebug.h>
/*!
  \internal
*/
void Q3Canvas::drawCanvasArea(const QRect& inarea, QPainter* p, bool /*double_buffer*/)
{
    QRect area=inarea.intersected(QRect(0,0,width(),height()));

    if (!p) return; // Nothing to do.

    int lx=area.x()/chunksize;
    int ly=area.y()/chunksize;
    int mx=area.right()/chunksize;
    int my=area.bottom()/chunksize;
    if (mx>=chwidth)
	mx=chwidth-1;
    if (my>=chheight)
	my=chheight-1;

    Q3CanvasItemList allvisible;

    // Stores the region within area that need to be drawn. It is relative
    // to area.topLeft()  (so as to keep within bounds of 16-bit XRegions)
    QRegion rgn;

    for (int x=lx; x<=mx; x++) {
	for (int y=ly; y<=my; y++) {
	    // Only reset change if all views updating, and
	    // wholy within area. (conservative:  ignore entire boundary)
	    //
	    // Disable this to help debugging.
	    //
	    if (!p) {
		if (chunk(x,y).takeChange()) {
		    // ### should at least make bands
		    rgn |= QRegion(x*chunksize-area.x(),y*chunksize-area.y(),
                                   chunksize,chunksize);
		    allvisible += *chunk(x,y).listPtr();
		}
	    } else {
		allvisible += *chunk(x,y).listPtr();
	    }
	}
    }
    allvisible.sort();

    drawBackground(*p,area);
    allvisible.drawUnique(*p);
    drawForeground(*p,area);
}

/*!
\internal
This method to informs the Q3Canvas that a given chunk is
`dirty' and needs to be redrawn in the next Update.

(\a x,\a y) is a chunk location.

The sprite classes call this. Any new derived class of Q3CanvasItem
must do so too. SetChangedChunkContaining can be used instead.
*/
void Q3Canvas::setChangedChunk(int x, int y)
{
    if (validChunk(x,y)) {
	Q3CanvasChunk& ch=chunk(x,y);
	ch.change();
    }
}

/*!
\internal
This method to informs the Q3Canvas that the chunk containing a given
pixel is `dirty' and needs to be redrawn in the next Update.

(\a x,\a y) is a pixel location.

The item classes call this. Any new derived class of Q3CanvasItem must
do so too. SetChangedChunk can be used instead.
*/
void Q3Canvas::setChangedChunkContaining(int x, int y)
{
    if (x>=0 && x<width() && y>=0 && y<height()) {
	Q3CanvasChunk& chunk=chunkContaining(x,y);
	chunk.change();
    }
}

/*!
\internal
This method adds the Q3CanvasItem \a g to the list of those which need to be
drawn if the given chunk at location (\a x, \a y) is redrawn. Like
SetChangedChunk and SetChangedChunkContaining, this method marks the
chunk as `dirty'.
*/
void Q3Canvas::addItemToChunk(Q3CanvasItem* g, int x, int y)
{
    if (validChunk(x,y)) {
	chunk(x,y).add(g);
    }
}

/*!
\internal
This method removes the Q3CanvasItem \a g from the list of those which need to
be drawn if the given chunk at location (\a x, \a y) is redrawn. Like
SetChangedChunk and SetChangedChunkContaining, this method marks the chunk
as `dirty'.
*/
void Q3Canvas::removeItemFromChunk(Q3CanvasItem* g, int x, int y)
{
    if (validChunk(x,y)) {
	chunk(x,y).remove(g);
    }
}


/*!
\internal
This method adds the Q3CanvasItem \a g to the list of those which need to be
drawn if the chunk containing the given pixel (\a x, \a y) is redrawn. Like
SetChangedChunk and SetChangedChunkContaining, this method marks the
chunk as `dirty'.
*/
void Q3Canvas::addItemToChunkContaining(Q3CanvasItem* g, int x, int y)
{
    if (x>=0 && x<width() && y>=0 && y<height()) {
	chunkContaining(x,y).add(g);
    }
}

/*!
\internal
This method removes the Q3CanvasItem \a g from the list of those which need to
be drawn if the chunk containing the given pixel (\a x, \a y) is redrawn.
Like SetChangedChunk and SetChangedChunkContaining, this method
marks the chunk as `dirty'.
*/
void Q3Canvas::removeItemFromChunkContaining(Q3CanvasItem* g, int x, int y)
{
    if (x>=0 && x<width() && y>=0 && y<height()) {
	chunkContaining(x,y).remove(g);
    }
}

/*!
    Returns the color set by setBackgroundColor(). By default, this is
    white.