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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"><html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
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<h1 align=center>QCanvas Class Reference<br><small>[ <a href="canvas.html">canvas module</a> ]</small></h1><br clear="all">
<p>
The QCanvas class is a 2D graphic area upon which <a href="qcanvasitem.html">QCanvasItem</a> objects exist.
<a href="#details">More...</a>
<p>
<code>#include <<a href="qcanvas-h.html">qcanvas.h</a>></code>
<p>
Inherits <a href="qobject.html">QObject</a>.
<p><a href="qcanvas-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li><div class="fn"><a href="#a54cbd"><b>QCanvas</b></a>(QObject*parent=0, constchar*name=0)</div>
<li><div class="fn"><a href="#671218"><b>QCanvas</b></a>(intw, inth)</div>
<li><div class="fn"><a href="#d08931"><b>QCanvas</b></a>(QPixmapp, inth, intv, inttilewidth, inttileheight)</div>
<li><div class="fn">virtual<a href="#591f67"><b>~QCanvas</b></a>()</div>
<li><div class="fn">virtualvoid<a href="#6d12f0"><b>setTiles</b></a>(QPixmaptiles, inth, intv, inttilewidth, inttileheight)</div>
<li><div class="fn">virtualvoid<a href="#c9fae8"><b>setBackgroundPixmap</b></a>(constQPixmap&p)</div>
<li><div class="fn">QPixmap<a href="#9b411e"><b>backgroundPixmap</b></a>()const</div>
<li><div class="fn">virtualvoid<a href="#e54d66"><b>setBackgroundColor</b></a>(constQColor&c)</div>
<li><div class="fn">QColor<a href="#09f2f9"><b>backgroundColor</b></a>()const</div>
<li><div class="fn">virtualvoid<a href="#02d528"><b>setTile</b></a>(intx, inty, inttilenum)</div>
<li><div class="fn">int<a href="#3ab1ee"><b>tile</b></a>(intx, inty)const</div>
<li><div class="fn">int<a href="#4aeda7"><b>tilesHorizontally</b></a>()const</div>
<li><div class="fn">int<a href="#7c95d2"><b>tilesVertically</b></a>()const</div>
<li><div class="fn">int<a href="#01280e"><b>tileWidth</b></a>()const</div>
<li><div class="fn">int<a href="#10e73b"><b>tileHeight</b></a>()const</div>
<li><div class="fn">virtualvoid<a href="#b34c7b"><b>resize</b></a>(intwidth, intheight)</div>
<li><div class="fn">int<a href="#274355"><b>width</b></a>()const</div>
<li><div class="fn">int<a href="#69f34f"><b>height</b></a>()const</div>
<li><div class="fn">QSize<a href="#c36672"><b>size</b></a>()const</div>
<li><div class="fn">bool<a href="#5dc8c7"><b>onCanvas</b></a>(intx, inty)const</div>
<li><div class="fn">bool<a href="#d90fa0"><b>onCanvas</b></a>(constQPoint&p)const</div>
<li><div class="fn">bool<a href="#888c39"><b>validChunk</b></a>(intx, inty)const</div>
<li><div class="fn">bool<a href="#2c6ac2"><b>validChunk</b></a>(constQPoint&p)const</div>
<li><div class="fn">int<a href="#a3c936"><b>chunkSize</b></a>()const</div>
<li><div class="fn">virtualvoid<a href="#505fb6"><b>retune</b></a>(intchunksize, intmaxclusters=100)</div>
<li><div class="fn">bool<b>sameChunk</b>(intx1, inty1, intx2, inty2)const(internal)</div>
<li><div class="fn">virtualvoid<b>setChangedChunk</b>(inti, intj)(internal)</div>
<li><div class="fn">virtualvoid<b>setChangedChunkContaining</b>(intx, inty)(internal)</div>
<li><div class="fn">virtualvoid<a href="#885be6"><b>setAllChanged</b></a>()</div>
<li><div class="fn">virtualvoid<a href="#695ead"><b>setChanged</b></a>(constQRect&inarea)</div>
<li><div class="fn">void<b>addItemToChunk</b>(QCanvasItem*, inti, intj)(internal)</div>
<li><div class="fn">void<b>removeItemFromChunk</b>(QCanvasItem*, inti, intj)(internal)</div>
<li><div class="fn">void<b>addItemToChunkContaining</b>(QCanvasItem*, intx, inty)(internal)</div>
<li><div class="fn">void<b>removeItemFromChunkContaining</b>(QCanvasItem*, intx, inty)(internal)</div>
<li><div class="fn">QCanvasItemList<a href="#471657"><b>allItems</b></a>()</div>
<li><div class="fn">QCanvasItemList<a href="#59f4a6"><b>collisions</b></a>(constQPoint&)const</div>
<li><div class="fn">QCanvasItemList<a href="#bab397"><b>collisions</b></a>(constQRect&)const</div>
<li><div class="fn">QCanvasItemList<a href="#f745b0"><b>collisions</b></a>(constQPointArray&pa, constQCanvasItem*item, boolexact)const</div>
<li><div class="fn">virtualvoid<b>addView</b>(QCanvasView*)(internal)</div>
<li><div class="fn">virtualvoid<b>removeView</b>(QCanvasView*)(internal)</div>
<li><div class="fn">void<b>drawArea</b>(constQRect&, QPainter*p=0, booldouble_buffer=TRUE)(internal)</div>
<li><div class="fn">virtualvoid<b>addItem</b>(QCanvasItem*)(internal)</div>
<li><div class="fn">virtualvoid<b>addAnimation</b>(QCanvasItem*)(internal)</div>
<li><div class="fn">virtualvoid<b>removeItem</b>(QCanvasItem*)(internal)</div>
<li><div class="fn">virtualvoid<b>removeAnimation</b>(QCanvasItem*)(internal)</div>
<li><div class="fn">virtualvoid<a href="#d0b96b"><b>setAdvancePeriod</b></a>(intms)</div>
<li><div class="fn">virtualvoid<a href="#ed8439"><b>setUpdatePeriod</b></a>(intms)</div>
<li><div class="fn">virtualvoid<a href="#ee851f"><b>setDoubleBuffering</b></a>(booly)</div>
</ul>
<h2>Public Slots</h2>
<ul>
<li><div class="fn">virtualvoid<a href="#292e63"><b>advance</b></a>()</div>
<li><div class="fn">virtualvoid<a href="#16e8be"><b>update</b></a>()</div>
</ul>
<h2>Signals</h2>
<ul>
<li><div class="fn">void<a href="#da3946"><b>resized</b></a>()</div>
</ul>
<h2>Protected Members</h2>
<ul>
<li><div class="fn">virtualvoid<a href="#4d393e"><b>drawBackground</b></a>(QPainter&, constQRect&area)</div>
<li><div class="fn">virtualvoid<a href="#dc77cc"><b>drawForeground</b></a>(QPainter&, constQRect&area)</div>
</ul>
<hr><h2><a name="details"></a>Detailed Description</h2>
The QCanvas class is a 2D graphic area upon which <a href="qcanvasitem.html">QCanvasItem</a> objects exist.
<p>
A QCanvas contains any number of QCanvasItem subclassed objects and has
any number of <a href="qcanvasview.html">QCanvasView</a> widgets observing some part of the canvas.
<p>A canvas containing
many items is different to a widgets containing many subwidgets in the
following ways:
<p><ul>
<li>Items are drawn much faster than widgets, especially when non-rectangular.
<li>Items use less memory than widgets.
<li>You can do efficient item-to-item hit tests ("collision detection")
with items in a canvas.
<li>Finding items in an area is efficient.
<li>You can have multiple views of a canvas.
</ul>
<p>Widgets of course offer richer functionality, such as hierarchies,
events, layout, etc.
<p><h3>Drawing</h3>
<p>A canvas has a solid background and a foreground. By default, the canvas will
have a white background, which can be changed with <a href="#e54d66">setBackgroundColor</a>().
If you want an image, use <a href="#c9fae8">setBackgroundPixmap</a>(). A third option is to use
<i>tiles</i>, where the canvas background is
a matrix of small images all the same size,
each chosen from a defined larger pixmap. See <a href="#6d12f0">setTiles</a>().
<p>On top of the background are objects of QCanvasItems subclasses. Each item
has a Z-height (see <a href="qcanvasitem.html#929f06">QCanvasItem::z</a>()), with the lower-Z items on the background
and higher-Z items on top of them.
<p>Above everything in the canvas is the foreground, as defined by the
<a href="#dc77cc">drawForeground</a>() function. By default this function draws nothing.
<p>Changes to the items on the canvas are refreshed to the views whenever
<a href="#16e8be">update</a>() is called, including creation of new items,
movement of item, change of shape,
change of visibility, and destruction.
<p>Note that like QWidgets, QCanvasItems are always hidden when they are created,
so you must show() them some time after creating them if you wish them to
be visible.
<p><h3>Animation</h3>
<p>QCanvas has some built-in animation features. If you call <a href="qcanvasitem.html#eb673b">QCanvasItem::setVelocity</a>()
on an item, it will move forward whenever <a href="#292e63">advance</a>() is call. The advance() function
also calls update(), so you only need to call one or the other. If no items
have a velocity, then advance() is the same as update().
<p>You can have advance() or update() called automatically with <a href="#d0b96b">setAdvancePeriod</a>()
or <a href="#ed8439">setUpdatePeriod</a>() respectively.
<p><h3>Collision Detection</h3>
<p>Items on the canvas can be tested for collisions with these functions, each of
which returns a list of items which match the hit, sorted from top to bottom
(ie. by decreasing QCanvasItem::z() value).
<p><ul>
<li><a href="#59f4a6">collisions</a>(<a href="qpoint.html">QPoint</a>) - items which will collide with a point.
<li>collisions(<a href="qrect.html">QRect</a>) - items which will collide with a rectangle.
</ul>
<p>You can also test for item-to-item collisions with <a href="qcanvasitem.html#62cd80">QCanvasItem::collisions</a>().
<hr><h2>Member Function Documentation</h2>
<h3 class="fn"><a name="a54cbd"></a>QCanvas::QCanvas(<a href="qobject.html">QObject</a>*parent=0, constchar*name=0)</h3>
<p>Create a QCanvas with no size.
You will want to call <a href="#b34c7b">resize</a>(int,int) at some time after creation.
<h3 class="fn"><a name="d08931"></a>QCanvas::QCanvas(<a href="qpixmap.html">QPixmap</a>p, inth, intv, inttilewidth, inttileheight)</h3>
<p>Constructs a QCanvas which will be composed of
<em>h</em> tiles horizontally and <em>v</em> tiles vertically. Each tile
will be an image <em>tilewidth</em> by <em>tileheight</em> pixels from
pixmap <em>p.</em>
<p>The pixmap <em>p</em> is a list of tiles, arranged left to right,
top to bottom, with tile 0 in the top-left corner, tile 1 next
to the right, and so on.
<p>The QCanvas is initially sized to show exactly the given number
of tiles horizontally and vertically. If it is resized to be larger,
the entire matrix of tiles will be repeated as much as necessary to
cover the area. If it is smaller, tiles to
the right and bottom will not be visible.
<h3 class="fn"><a name="671218"></a>QCanvas::QCanvas(intw, inth)</h3>
<p>Constructs a QCanvas with that is <code>w</code> pixels wide and <code>h</code> pixels high.
<h3 class="fn"><a name="591f67"></a>QCanvas::~QCanvas() <code>[virtual]</code></h3>
<p>Destructs the canvas. Does also destroy all items on the canvas.
<h3 class="fn">void<a name="292e63"></a>QCanvas::advance() <code>[virtualslot]</code></h3>
<p>Advances the animation of items on the canvas and refreshes all
changes to all views of the canvas.
<p>The advance is done in two phases. In phase 0, the
QCanvasItem:advance() function of each animated item is called with
paramater 0. Then all items are called again, with parameter 1. In
phase 0, the 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 items should change
positions, ignoring any other items on the canvas. This two-phase
approach allows for considerations of "fairness", though no
<a href="qcanvasitem.html">QCanvasItem</a> subclasses supplied with Qt do anything interesting in
phase 0.
<p>The canvas can be configured to call this function periodically with
<a href="#d0b96b">setAdvancePeriod</a>().
<p>See also <a href="#16e8be">update</a>().
<h3 class="fn">QCanvasItemList<a name="471657"></a>QCanvas::allItems()</h3>
<p>Returns a list of all items in the canvas.
<h3 class="fn"><a href="qcolor.html">QColor</a><a name="09f2f9"></a>QCanvas::backgroundColor()const</h3>
<p>Returns the color set by <a href="#e54d66">setBackgroundColor</a>().
By default, this is white.
<p>Note that this function is not a reimplementation
of <a href="qwidget.html#d5be64">QWidget::backgroundColor</a>() (QCanvas is not a subclass
of <a href="qwidget.html">QWidget</a>), but all QCanvasViews that are viewing the
canvas will set their backgrounds to this
<p>See also <a href="#e54d66">setBackgroundColor</a>() and <a href="#9b411e">backgroundPixmap</a>().
<h3 class="fn"><a href="qpixmap.html">QPixmap</a><a name="9b411e"></a>QCanvas::backgroundPixmap()const</h3>
<p>Returns the pixmap set by <a href="#c9fae8">setBackgroundPixmap</a>(). By default,
this is a null pixmap.
<p>See also <a href="#c9fae8">setBackgroundPixmap</a>() and <a href="#09f2f9">backgroundColor</a>().
<h3 class="fn">int<a name="a3c936"></a>QCanvas::chunkSize()const</h3>
<p>Returns the chunk size of the canvas as set at construction.
<p>See also <a href="#505fb6">retune</a>().
<h3 class="fn">QCanvasItemList<a name="59f4a6"></a>QCanvas::collisions(const<a href="qpoint.html">QPoint</a>&p)const</h3>
<p>Returns a list of items which intersect with the point <em>p,</em>
sorted from shallowest to deepest.
<h3 class="fn">QCanvasItemList<a name="f745b0"></a>QCanvas::collisions(const<a href="qpointarray.html">QPointArray</a>&chunklist, const<a href="qcanvasitem.html">QCanvasItem</a>*item, boolexact)const</h3>
<p>Returns a list of items which intersect with the chunks listed
in <em>chunklist,</em> excluding <em>item.</em> If <em>exact</em> is TRUE, only
only those which actually <a href="qcanvasitem.html#1d22d3">QCanvasItem::collidesWith</a>() <em>item</em>
are returned, otherwise items are included just for being in the
chunks.
<p>This is a utility function mainly used to implement the simpler
<a href="qcanvasitem.html#62cd80">QCanvasItem::collisions</a>() function.
<h3 class="fn">QCanvasItemList<a name="bab397"></a>QCanvas::collisions(const<a href="qrect.html">QRect</a>&r)const</h3>
<p>Returns a list of items which intersect with the rectangle <em>r,</em>
sorted from shallowest to deepest.
<h3 class="fn">void<a name="4d393e"></a>QCanvas::drawBackground(<a href="qpainter.html">QPainter</a>&painter, const<a href="qrect.html">QRect</a>&clip) <code>[virtualprotected]</code></h3>
<p>This virtual function is called for all updates of the QCanvas.
It renders any background graphics. If the canvas has a background
pixmap or a tiled background, that graphic is used, otherwise the
canvas is cleared in the background color.
<p>If the graphics for an area change, you must explicitly call
<a href="#695ead">setChanged</a>(const <a href="qrect.html">QRect</a>&) for the result to be visible when <a href="#16e8be">update</a>()
is next called.
<p>See also <a href="#e54d66">setBackgroundColor</a>(), <a href="#c9fae8">setBackgroundPixmap</a>() and <a href="#6d12f0">setTiles</a>().
<h3 class="fn">void<a name="dc77cc"></a>QCanvas::drawForeground(<a href="qpainter.html">QPainter</a>&painter, const<a href="qrect.html">QRect</a>&clip) <code>[virtualprotected]</code></h3>
<p>This virtual function is called for all updates of the QCanvas.
It renders any foreground graphics.
<p>The same warnings regarding change apply to this method as for
<a href="#4d393e">drawBackground</a>().
<p>The default is to draw nothing.
<h3 class="fn">int<a name="69f34f"></a>QCanvas::height()const</h3>
<p>Returns the height of the canvas, in pixels.
<h3 class="fn">bool<a name="d90fa0"></a>QCanvas::onCanvas(const<a href="qpoint.html">QPoint</a>&p)const</h3>
<p>Returns whether the pixel position <em>p</em> is on the canvas.
<h3 class="fn">bool<a name="5dc8c7"></a>QCanvas::onCanvas(intx, inty)const</h3>
<p>Returns whether the pixel position (<em>x, y)</em> is on the canvas.
<h3 class="fn">void<a name="b34c7b"></a>QCanvas::resize(intw, inth) <code>[virtual]</code></h3>
<p>Changes the size of the QCanvas. This is a slow operation.
<h3 class="fn">void<a name="da3946"></a>QCanvas::resized() <code>[signal]</code></h3>
<p>This signal is emitted whenever the canvas is resized. Each <a href="qcanvasview.html">QCanvasView</a>
connects to this signal to keep the scrollview size correct.
<h3 class="fn">void<a name="505fb6"></a>QCanvas::retune(intchunksze, intmxclusters=100) <code>[virtual]</code></h3>
<p>Change the efficiency tuning parameters to <em>mxclusters</em> clusters,
each of size <em>chunksze</em> (square). This is a slow operation if you
have many objects on the canvas.
<p>Internally, a canvas uses a low-resolution "chunk matrix" to keep
track of all the items in the canvas. In Qt 2.2, the default for a
1024x1024 pixel canvas is to have a 64x64 chunk matrix, where each of
those chunks collects items in a 16x16 pixel square.
<p>This default is also affected by <a href="#6d12f0">setTiles</a>(). You can tune this default
by using retune(), for example if you have a very large canvas and
want to trade off speed for memory then you might set the chunk size
to 32 or 64.
<p><em>chunksze</em> is the size of square chunk used to break up the QCanvas
into area to be considered for redrawing. It should be about the
average size of items in the QCanvas. Chunks too small increase the
amount of calculation required when drawing. Chunks too large
increase the amount of drawing that is needed.
<p><em>mxclusters</em> is the number of rectangular groups of chunks that will
be separately drawn. If the QCanvas has a large number of small,
dispersed items, this should be about that number. The more clusters
the slower the redraw, but also the bigger clusters are the slower the
redraw, so a balance is needed. Testing indicates that a large number
of clusters is almost always best.
<h3 class="fn">void<a name="d0b96b"></a>QCanvas::setAdvancePeriod(intms) <code>[virtual]</code></h3>
<p>Sets the canvas to call <a href="#292e63">advance</a>() every <em>ms</em> milliseconds.
Any previous setting by setAdvancePeriod() or <a href="#ed8439">setUpdatePeriod</a>() is cancelled.
<h3 class="fn">void<a name="885be6"></a>QCanvas::setAllChanged() <code>[virtual]</code></h3>
<p>Sets all views of the canvas to be entirely redrawn when
<a href="#16e8be">update</a>() is next called.
<h3 class="fn">void<a name="e54d66"></a>QCanvas::setBackgroundColor(const<a href="qcolor.html">QColor</a>&c) <code>[virtual]</code></h3>
<p>Sets the solid background to be the color <em>c.</em>
<p>See also <a href="#09f2f9">backgroundColor</a>(), <a href="#c9fae8">setBackgroundPixmap</a>() and <a href="#6d12f0">setTiles</a>().
<h3 class="fn">void<a name="c9fae8"></a>QCanvas::setBackgroundPixmap(const<a href="qpixmap.html">QPixmap</a>&p) <code>[virtual]</code></h3>
<p>Sets the solid background to be <em>p,</em> repeated as necessary to
cover the entire canvas.
<p>See also <a href="#9b411e">backgroundPixmap</a>(), <a href="#e54d66">setBackgroundColor</a>() and <a href="#6d12f0">setTiles</a>().
<h3 class="fn">void<a name="695ead"></a>QCanvas::setChanged(const<a href="qrect.html">QRect</a>&area) <code>[virtual]</code></h3>
<p>Sets all views of <em>area</em> to be entirely redrawn when
<a href="#16e8be">update</a>() is next called.
<h3 class="fn">void<a name="ee851f"></a>QCanvas::setDoubleBuffering(booly) <code>[virtual]</code></h3>
<p>Turns double-buffering on if <em>y</em> is TRUE, or off if it is
FALSE. The default is to use double-buffering.
<p>Turning off double-buffering casuses the redrawn areas to flicker a
bit. This can help understand the the optimizations made by QCanvas
and also gives a (usually small) performance improvement.
<h3 class="fn">void<a name="02d528"></a>QCanvas::setTile(intx, inty, inttilenum) <code>[virtual]</code></h3>
<p>Sets the tile at (<em>x, y)</em> to use tile number <em>tilenum,</em>
which is an index into the tile pixmaps. The canvas will update
appropriately when <a href="#16e8be">update</a>() is next called.
<p>The images are taken from the pixmap set by <a href="#6d12f0">setTiles</a>() and are
arranged in the pixmap left to right, top to bottom, with tile 0 in
the top-left corner, tile 1 next to the right, and so on.
<p>See also <a href="#3ab1ee">tile</a>() and <a href="#6d12f0">setTiles</a>().
<h3 class="fn">void<a name="6d12f0"></a>QCanvas::setTiles(<a href="qpixmap.html">QPixmap</a>p, inth, intv, inttilewidth, inttileheight) <code>[virtual]</code></h3>
<p>Sets the QCanvas to be composed of <em>h</em> tiles horizontally and <em>v</em> tiles vertically. Each tile will be an image <em>tilewidth</em> by <em>tileheight</em> pixels from pixmap <em>p.</em>
<p>The pixmap <em>p</em> contains the tiles arranged left to right, top to
bottom, with tile 0 in the top-left corner, tile 1 to the right of
tile 0, and so on.
<p>If the QCanvas is larger than the matrix of tiles, the entire matrix
is repeated as necessary to cover the area. If it is smaller, tiles
to the right and bottom are not visible.
<p>The width and height of <em>p</em> must be multiples of <em>tilewidth</em> and
<em>tileheight.</em> If they are not, the action of this function is
unspecified.
<h3 class="fn">void<a name="ed8439"></a>QCanvas::setUpdatePeriod(intms) <code>[virtual]</code></h3>
<p>Sets the canvas to call <a href="#16e8be">update</a>() every <em>ms</em> milliseconds.
Any previous setting by <a href="#d0b96b">setAdvancePeriod</a>() or setUpdatePeriod() is cancelled.
<h3 class="fn"><a href="qsize.html">QSize</a><a name="c36672"></a>QCanvas::size()const</h3>
<p>Returns the size of the canvas, in pixels.
<h3 class="fn">int<a name="3ab1ee"></a>QCanvas::tile(intx, inty)const</h3>
<p>Returns the tile at (<em>x, y).</em> Initially, all tiles are 0.<p><b>Warning:</b> The parameters must be within range.
<p>See also <a href="#02d528">setTile</a>().
<h3 class="fn">int<a name="10e73b"></a>QCanvas::tileHeight()const</h3>
<p>Returns the height of each tile.
<h3 class="fn">int<a name="01280e"></a>QCanvas::tileWidth()const</h3>
<p>Returns the width of each tile.
<h3 class="fn">int<a name="4aeda7"></a>QCanvas::tilesHorizontally()const</h3>
<p>Returns the number of tiles horizontally.
<h3 class="fn">int<a name="7c95d2"></a>QCanvas::tilesVertically()const</h3>
<p>Returns the number of tiles vertically.
<h3 class="fn">void<a name="16e8be"></a>QCanvas::update() <code>[virtualslot]</code></h3>
<p>Refreshes all changes to all views of the canvas.
<p>See also <a href="#292e63">advance</a>().
<h3 class="fn">bool<a name="2c6ac2"></a>QCanvas::validChunk(const<a href="qpoint.html">QPoint</a>&p)const</h3>
<p>Returns whether the chunk position <em>p</em> is on the canvas.
<h3 class="fn">bool<a name="888c39"></a>QCanvas::validChunk(intx, inty)const</h3>
<p>Returns whether the chunk position (<em>x, y)</em> is on the canvas.
<h3 class="fn">int<a name="274355"></a>QCanvas::width()const</h3>
<p>Returns the width of the canvas, in pixels.
<h3 class="fn">void<a name="bd0643"></a>QCanvas::addAnimation(<a href="qcanvasitem.html">QCanvasItem</a>*item) <code>[virtual]</code></h3>
<p>For internal use only.
<h3 class="fn">void<a name="e50afd"></a>QCanvas::addItem(<a href="qcanvasitem.html">QCanvasItem</a>*item) <code>[virtual]</code></h3>
<p>For internal use only.
<h3 class="fn">void<a name="5f878e"></a>QCanvas::addItemToChunk(<a href="qcanvasitem.html">QCanvasItem</a>*g, intx, inty)</h3>
<p>For internal use only.
<h3 class="fn">void<a name="7078d6"></a>QCanvas::addItemToChunkContaining(<a href="qcanvasitem.html">QCanvasItem</a>*g, intx, inty)</h3>
<p>For internal use only.
<h3 class="fn">void<a name="5b4af3"></a>QCanvas::addView(<a href="qcanvasview.html">QCanvasView</a>*view) <code>[virtual]</code></h3>
<p>For internal use only.
<h3 class="fn">void<a name="fbf3aa"></a>QCanvas::drawArea(const<a href="qrect.html">QRect</a>&inarea, <a href="qpainter.html">QPainter</a>*p=0, booldouble_buffer=TRUE)</h3>
<p>For internal use only.
<h3 class="fn">void<a name="0adbc7"></a>QCanvas::removeAnimation(<a href="qcanvasitem.html">QCanvasItem</a>*item) <code>[virtual]</code></h3>
<p>For internal use only.
<h3 class="fn">void<a name="8efb0e"></a>QCanvas::removeItem(<a href="qcanvasitem.html">QCanvasItem</a>*item) <code>[virtual]</code></h3>
<p>For internal use only.
<h3 class="fn">void<a name="db072b"></a>QCanvas::removeItemFromChunk(<a href="qcanvasitem.html">QCanvasItem</a>*g, intx, inty)</h3>
<p>For internal use only.
<h3 class="fn">void<a name="87b332"></a>QCanvas::removeItemFromChunkContaining(<a href="qcanvasitem.html">QCanvasItem</a>*g, intx, inty)</h3>
<p>For internal use only.
<h3 class="fn">void<a name="b5fec3"></a>QCanvas::removeView(<a href="qcanvasview.html">QCanvasView</a>*view) <code>[virtual]</code></h3>
<p>For internal use only.
<h3 class="fn">bool<a name="13ea9d"></a>QCanvas::sameChunk(intx1, inty1, intx2, inty2)const</h3>
<p>For internal use only.
<h3 class="fn">void<a name="611ae7"></a>QCanvas::setChangedChunk(intx, inty) <code>[virtual]</code></h3>
<p>For internal use only.
<h3 class="fn">void<a name="3a3fea"></a>QCanvas::setChangedChunkContaining(intx, inty) <code>[virtual]</code></h3>
<p>For internal use only.
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