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diff --git a/doc/html/qcanvasview.html b/doc/html/qcanvasview.html new file mode 100644 index 0000000..6203f0b --- /dev/null +++ b/doc/html/qcanvasview.html @@ -0,0 +1,190 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/src/canvas/qcanvas.cpp:3456 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QCanvasView Class</title> +<style type="text/css"><!-- +fn { margin-left: 1cm; text-indent: -1cm; } +a:link { color: #004faf; text-decoration: none } +a:visited { color: #672967; text-decoration: none } +body { background: #ffffff; color: black; } +--></style> +</head> +<body> + +<table border="0" cellpadding="0" cellspacing="0" width="100%"> +<tr bgcolor="#E5E5E5"> +<td valign=center> + <a href="index.html"> +<font color="#004faf">Home</font></a> + | <a href="classes.html"> +<font color="#004faf">All Classes</font></a> + | <a href="mainclasses.html"> +<font color="#004faf">Main Classes</font></a> + | <a href="annotated.html"> +<font color="#004faf">Annotated</font></a> + | <a href="groups.html"> +<font color="#004faf">Grouped Classes</font></a> + | <a href="functions.html"> +<font color="#004faf">Functions</font></a> +</td> +<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QCanvasView Class Reference<br><small>[<a href="canvas.html">canvas module</a>]</small></h1> + +<p>The QCanvasView class provides an on-screen view of a QCanvas. +<a href="#details">More...</a> +<p><tt>#include <<a href="qcanvas-h.html">qcanvas.h</a>></tt> +<p>Inherits <a href="qscrollview.html">QScrollView</a>. +<p><a href="qcanvasview-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn><a href="#QCanvasView"><b>QCanvasView</b></a> ( QWidget * parent = 0, const char * name = 0, WFlags f = 0 )</li> +<li class=fn><a href="#QCanvasView-2"><b>QCanvasView</b></a> ( QCanvas * canvas, QWidget * parent = 0, const char * name = 0, WFlags f = 0 )</li> +<li class=fn><a href="#~QCanvasView"><b>~QCanvasView</b></a> ()</li> +<li class=fn>QCanvas * <a href="#canvas"><b>canvas</b></a> () const</li> +<li class=fn>void <a href="#setCanvas"><b>setCanvas</b></a> ( QCanvas * canvas )</li> +<li class=fn>const QWMatrix & <a href="#worldMatrix"><b>worldMatrix</b></a> () const</li> +<li class=fn>const QWMatrix & <a href="#inverseWorldMatrix"><b>inverseWorldMatrix</b></a> () const</li> +<li class=fn>bool <a href="#setWorldMatrix"><b>setWorldMatrix</b></a> ( const QWMatrix & wm )</li> +</ul> +<h2>Protected Members</h2> +<ul> +<li class=fn>virtual void <a href="#drawContents"><b>drawContents</b></a> ( QPainter * p, int cx, int cy, int cw, int ch )</li> +<li class=fn>virtual QSize <a href="#sizeHint"><b>sizeHint</b></a> () const</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The QCanvasView class provides an on-screen view of a <a href="qcanvas.html">QCanvas</a>. + +<p> + + +<p> A QCanvasView is widget which provides a view of a QCanvas. +<p> If you want users to be able to interact with a canvas view, +subclass QCanvasView. You might then reimplement +<a href="qscrollview.html#contentsMousePressEvent">QScrollView::contentsMousePressEvent</a>(). For example, assuming no +<a href="qwmatrix.html#TransformationMode">transformation matrix</a> is set: +<p> <pre> + void MyCanvasView::contentsMousePressEvent( <a href="qmouseevent.html">QMouseEvent</a>* e ) + { + <a href="qcanvasitemlist.html">QCanvasItemList</a> l = <a href="#canvas">canvas</a>()->collisions(e-><a href="qmouseevent.html#pos">pos</a>()); + for (QCanvasItemList::Iterator it=l.<a href="qvaluelist.html#begin">begin</a>(); it!=l.<a href="qvaluelist.html#end">end</a>(); ++it) { + if ( (*it)->rtti() == QCanvasRectangle::RTTI ) + <a href="qapplication.html#qDebug">qDebug</a>("A QCanvasRectangle lies somewhere at this point"); + } + } + </pre> + +<p> The canvas view shows canvas <a href="#canvas">canvas</a>(); this can be changed using +<a href="#setCanvas">setCanvas</a>(). +<p> A transformation matrix can be used to transform the view of the +canvas in various ways, for example, zooming in or out or rotating. +For example: +<p> <pre> + <a href="qwmatrix.html">QWMatrix</a> wm; + wm.<a href="qwmatrix.html#scale">scale</a>( 2, 2 ); // Zooms in by 2 times + wm.<a href="qwmatrix.html#rotate">rotate</a>( 90 ); // Rotates 90 degrees counter clockwise + // around the origin. + wm.<a href="qwmatrix.html#translate">translate</a>( 0, -canvas->height() ); + // moves the canvas down so what was visible + // before is still visible. + myCanvasView->setWorldMatrix( wm ); + </pre> + +<p> Use <a href="#setWorldMatrix">setWorldMatrix</a>() to set the canvas view's world matrix: you must +ensure that the world matrix is invertible. The current world matrix +is retrievable with <a href="#worldMatrix">worldMatrix</a>(), and its inversion is retrievable +with <a href="#inverseWorldMatrix">inverseWorldMatrix</a>(). +<p> Example: +<p> The following code finds the part of the canvas that is visible in +this view, i.e. the bounding rectangle of the view in canvas coordinates. +<p> <pre> + <a href="qrect.html">QRect</a> rc = QRect( myCanvasView->contentsX(), myCanvasView->contentsY(), + myCanvasView->visibleWidth(), myCanvasView->visibleHeight() ); + <a href="qrect.html">QRect</a> canvasRect = myCanvasView->inverseWorldMatrix().mapRect(rc); + </pre> + +<p> <p>See also <a href="qwmatrix.html">QWMatrix</a>, <a href="qpainter.html#setWorldMatrix">QPainter::setWorldMatrix</a>(), <a href="graphics.html">Graphics Classes</a>, and <a href="images.html">Image Processing Classes</a>. + +<p> +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="QCanvasView"></a>QCanvasView::QCanvasView ( <a href="qwidget.html">QWidget</a> * parent = 0, const char * name = 0, WFlags f = 0 ) +</h3> +Constructs a QCanvasView with parent <em>parent</em>, and name <em>name</em>, +using the widget flags <em>f</em>. The canvas view is not associated +with a canvas, so you must to call <a href="#setCanvas">setCanvas</a>() to view a +canvas. + +<h3 class=fn><a name="QCanvasView-2"></a>QCanvasView::QCanvasView ( <a href="qcanvas.html">QCanvas</a> * canvas, <a href="qwidget.html">QWidget</a> * parent = 0, const char * name = 0, WFlags f = 0 ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Constructs a QCanvasView which views canvas <em>canvas</em>, with parent +<em>parent</em>, and name <em>name</em>, using the widget flags <em>f</em>. + +<h3 class=fn><a name="~QCanvasView"></a>QCanvasView::~QCanvasView () +</h3> +Destroys the canvas view. The associated canvas is <em>not</em> deleted. + +<h3 class=fn><a href="qcanvas.html">QCanvas</a> * <a name="canvas"></a>QCanvasView::canvas () const +</h3> + +<p> Returns a pointer to the canvas which the QCanvasView is currently +showing. + +<h3 class=fn>void <a name="drawContents"></a>QCanvasView::drawContents ( <a href="qpainter.html">QPainter</a> * p, int cx, int cy, int cw, int ch )<tt> [virtual protected]</tt> +</h3> +Repaints part of the <a href="qcanvas.html">QCanvas</a> that the canvas view is showing +starting at <em>cx</em> by <em>cy</em>, with a width of <em>cw</em> and a height of <em>ch</em> using the painter <em>p</em>. +<p> <b>Warning:</b> When double buffering is enabled, <a href="#drawContents">drawContents</a>() will +not respect the current settings of the painter when setting up +the painter for the double buffer (e.g., <a href="qscrollview.html#viewport">viewport</a>() and +window()). Also, be aware that <a href="qcanvas.html#update">QCanvas::update</a>() bypasses +drawContents(), which means any reimplementation of +drawContents() is not called. +<p> <p>See also <a href="qcanvas.html#setDoubleBuffering">QCanvas::setDoubleBuffering</a>(). + +<p>Reimplemented from <a href="qscrollview.html#drawContents">QScrollView</a>. +<h3 class=fn>const <a href="qwmatrix.html">QWMatrix</a> & <a name="inverseWorldMatrix"></a>QCanvasView::inverseWorldMatrix () const +</h3> +Returns a reference to the inverse of the canvas view's current +<a href="qwmatrix.html#TransformationMode">transformation matrix</a>. +<p> <p>See also <a href="#setWorldMatrix">setWorldMatrix</a>() and <a href="#worldMatrix">worldMatrix</a>(). + +<h3 class=fn>void <a name="setCanvas"></a>QCanvasView::setCanvas ( <a href="qcanvas.html">QCanvas</a> * canvas ) +</h3> +Sets the canvas that the QCanvasView is showing to the canvas <em>canvas</em>. + +<h3 class=fn>bool <a name="setWorldMatrix"></a>QCanvasView::setWorldMatrix ( const <a href="qwmatrix.html">QWMatrix</a> & wm ) +</h3> +Sets the <a href="qwmatrix.html#TransformationMode">transformation matrix</a> of the QCanvasView to <em>wm</em>. The +matrix must be invertible (i.e. if you create a world matrix that +zooms out by 2 times, then the inverse of this matrix is one that +will zoom in by 2 times). +<p> When you use this, you should note that the performance of the +QCanvasView will decrease considerably. +<p> Returns FALSE if <em>wm</em> is not invertable; otherwise returns TRUE. +<p> <p>See also <a href="#worldMatrix">worldMatrix</a>(), <a href="#inverseWorldMatrix">inverseWorldMatrix</a>(), and <a href="qwmatrix.html#isInvertible">QWMatrix::isInvertible</a>(). + +<p>Example: <a href="canvas-example.html#x2930">canvas/canvas.cpp</a>. +<h3 class=fn><a href="qsize.html">QSize</a> <a name="sizeHint"></a>QCanvasView::sizeHint () const<tt> [virtual protected]</tt> +</h3> +Suggests a size sufficient to view the entire canvas. + +<h3 class=fn>const <a href="qwmatrix.html">QWMatrix</a> & <a name="worldMatrix"></a>QCanvasView::worldMatrix () const +</h3> +Returns a reference to the canvas view's current <a href="qwmatrix.html#TransformationMode">transformation matrix</a>. +<p> <p>See also <a href="#setWorldMatrix">setWorldMatrix</a>() and <a href="#inverseWorldMatrix">inverseWorldMatrix</a>(). + +<p>Example: <a href="canvas-example.html#x2931">canvas/canvas.cpp</a>. +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">Qt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. 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