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diff --git a/doc/html/tqcanvaspolygonalitem.html b/doc/html/tqcanvaspolygonalitem.html new file mode 100644 index 00000000..2a877178 --- /dev/null +++ b/doc/html/tqcanvaspolygonalitem.html @@ -0,0 +1,235 @@ +<!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/tqcanvas.cpp:3725 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>TQCanvasPolygonalItem 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>TQCanvasPolygonalItem Class Reference<br><small>[<a href="canvas.html">canvas module</a>]</small></h1> + +<p>The TQCanvasPolygonalItem class provides a polygonal canvas item +on a TQCanvas. +<a href="#details">More...</a> +<p><tt>#include <<a href="tqcanvas-h.html">tqcanvas.h</a>></tt> +<p>Inherits <a href="tqcanvasitem.html">TQCanvasItem</a>. +<p>Inherited by <a href="tqcanvasrectangle.html">TQCanvasRectangle</a>, <a href="tqcanvaspolygon.html">TQCanvasPolygon</a>, <a href="tqcanvasline.html">TQCanvasLine</a>, and <a href="tqcanvasellipse.html">TQCanvasEllipse</a>. +<p><a href="tqcanvaspolygonalitem-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn><a href="#TQCanvasPolygonalItem"><b>TQCanvasPolygonalItem</b></a> ( TQCanvas * canvas )</li> +<li class=fn>virtual <a href="#~TQCanvasPolygonalItem"><b>~TQCanvasPolygonalItem</b></a> ()</li> +<li class=fn>virtual void <a href="#setPen"><b>setPen</b></a> ( TQPen p )</li> +<li class=fn>virtual void <a href="#setBrush"><b>setBrush</b></a> ( TQBrush b )</li> +<li class=fn>TQPen <a href="#pen"><b>pen</b></a> () const</li> +<li class=fn>TQBrush <a href="#brush"><b>brush</b></a> () const</li> +<li class=fn>virtual TQPointArray <a href="#areaPoints"><b>areaPoints</b></a> () const = 0</li> +<li class=fn>virtual TQPointArray <a href="#areaPointsAdvanced"><b>areaPointsAdvanced</b></a> () const</li> +<li class=fn>virtual TQRect <a href="#boundingRect"><b>boundingRect</b></a> () const</li> +<li class=fn>virtual int <a href="#rtti"><b>rtti</b></a> () const</li> +</ul> +<h2>Protected Members</h2> +<ul> +<li class=fn>virtual void <a href="#draw"><b>draw</b></a> ( TQPainter & p )</li> +<li class=fn>virtual void <a href="#drawShape"><b>drawShape</b></a> ( TQPainter & p ) = 0</li> +<li class=fn>bool <a href="#winding"><b>winding</b></a> () const</li> +<li class=fn>void <a href="#setWinding"><b>setWinding</b></a> ( bool enable )</li> +<li class=fn>void <a href="#invalidate"><b>invalidate</b></a> ()</li> +<li class=fn>bool <a href="#isValid"><b>isValid</b></a> () const</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The TQCanvasPolygonalItem class provides a polygonal canvas item +on a <a href="tqcanvas.html">TQCanvas</a>. + +<p> + + +<p> The mostly rectangular classes, such as <a href="tqcanvassprite.html">TQCanvasSprite</a> and +<a href="tqcanvastext.html">TQCanvasText</a>, use the object's bounding rectangle for movement, +repainting and collision calculations. For most other items, the +bounding rectangle can be far too large -- a diagonal line being +the worst case, and there are many other cases which are also bad. +TQCanvasPolygonalItem provides polygon-based bounding rectangle +handling, etc., which is much faster for non-rectangular items. +<p> Derived classes should try to define as small an area as possible +to maximize efficiency, but the polygon must <em>definitely</em> be +contained completely within the polygonal area. Calculating the +exact requirements is usually difficult, but if you allow a small +overestimate it can be easy and quick, while still getting almost +all of TQCanvasPolygonalItem's speed. +<p> Note that all subclasses <em>must</em> call <a href="tqcanvasitem.html#hide">hide</a>() in their destructor +since hide() needs to be able to access <a href="#areaPoints">areaPoints</a>(). +<p> Normally, TQCanvasPolygonalItem uses the odd-even algorithm for +determining whether an object intersects this object. You can +change this to the winding algorithm using <a href="#setWinding">setWinding</a>(). +<p> The bounding rectangle is available using <a href="#boundingRect">boundingRect</a>(). The +points bounding the polygonal item are retrieved with +areaPoints(). Use <a href="#areaPointsAdvanced">areaPointsAdvanced</a>() to retrieve the bounding +points the polygonal item <em>will</em> have after +<a href="tqcanvasitem.html#advance">TQCanvasItem::advance</a>(1) has been called. +<p> If the shape of the polygonal item is about to change while the +item is visible, call <a href="#invalidate">invalidate</a>() before updating with a +different result from <a href="#areaPoints">areaPoints</a>(). +<p> By default, TQCanvasPolygonalItem objects have a black pen and no +brush (the default <a href="ntqpen.html">TQPen</a> and <a href="ntqbrush.html">TQBrush</a> constructors). You can change +this with <a href="#setPen">setPen</a>() and <a href="#setBrush">setBrush</a>(), but note that some +TQCanvasPolygonalItem subclasses only use the brush, ignoring the +pen setting. +<p> The polygonal item can be drawn on a painter with <a href="#draw">draw</a>(). +Subclasses must reimplement <a href="#drawShape">drawShape</a>() to draw themselves. +<p> Like any other canvas item polygonal items can be moved with +<a href="tqcanvasitem.html#move">TQCanvasItem::move</a>() and <a href="tqcanvasitem.html#moveBy">TQCanvasItem::moveBy</a>(), or by setting coordinates +with <a href="tqcanvasitem.html#setX">TQCanvasItem::setX</a>(), <a href="tqcanvasitem.html#setY">TQCanvasItem::setY</a>() and <a href="tqcanvasitem.html#setZ">TQCanvasItem::setZ</a>(). +<p> <p>See also <a href="graphics.html">Graphics Classes</a> and <a href="images.html">Image Processing Classes</a>. + +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="TQCanvasPolygonalItem"></a>TQCanvasPolygonalItem::TQCanvasPolygonalItem ( <a href="tqcanvas.html">TQCanvas</a> * canvas ) +</h3> +Constructs a TQCanvasPolygonalItem on the canvas <em>canvas</em>. + +<h3 class=fn><a name="~TQCanvasPolygonalItem"></a>TQCanvasPolygonalItem::~TQCanvasPolygonalItem ()<tt> [virtual]</tt> +</h3> +Note that all subclasses <em>must</em> call <a href="tqcanvasitem.html#hide">hide</a>() in their destructor +since hide() needs to be able to access <a href="#areaPoints">areaPoints</a>(). + +<h3 class=fn><a href="ntqpointarray.html">TQPointArray</a> <a name="areaPoints"></a>TQCanvasPolygonalItem::areaPoints () const<tt> [pure virtual]</tt> +</h3> + +<p> This function must be reimplemented by subclasses. It <em>must</em> +return the points bounding (i.e. outside and not touching) the +shape or drawing errors will occur. + +<p>Reimplemented in <a href="tqcanvaspolygon.html#areaPoints">TQCanvasPolygon</a>. +<h3 class=fn><a href="ntqpointarray.html">TQPointArray</a> <a name="areaPointsAdvanced"></a>TQCanvasPolygonalItem::areaPointsAdvanced () const<tt> [virtual]</tt> +</h3> +Returns the points the polygonal item <em>will</em> have after +<a href="tqcanvasitem.html#advance">TQCanvasItem::advance</a>(1) is called, i.e. what the points are when +advanced by the current <a href="tqcanvasitem.html#xVelocity">xVelocity</a>() and <a href="tqcanvasitem.html#yVelocity">yVelocity</a>(). + +<h3 class=fn><a href="ntqrect.html">TQRect</a> <a name="boundingRect"></a>TQCanvasPolygonalItem::boundingRect () const<tt> [virtual]</tt> +</h3> +Returns the bounding rectangle of the polygonal item, based on +<a href="#areaPoints">areaPoints</a>(). + +<p>Reimplemented from <a href="tqcanvasitem.html#boundingRect">TQCanvasItem</a>. +<h3 class=fn><a href="ntqbrush.html">TQBrush</a> <a name="brush"></a>TQCanvasPolygonalItem::brush () const +</h3> + +<p> Returns the <a href="ntqbrush.html">TQBrush</a> used to fill the item, if filled. +<p> <p>See also <a href="#setBrush">setBrush</a>(). + +<h3 class=fn>void <a name="draw"></a>TQCanvasPolygonalItem::draw ( <a href="ntqpainter.html">TQPainter</a> & p )<tt> [virtual protected]</tt> +</h3> +Reimplemented from <a href="tqcanvasitem.html">TQCanvasItem</a>, this draws the polygonal item by +setting the pen and brush for the item on the painter <em>p</em> and +calling <a href="#drawShape">drawShape</a>(). + +<p>Reimplemented from <a href="tqcanvasitem.html#draw">TQCanvasItem</a>. +<h3 class=fn>void <a name="drawShape"></a>TQCanvasPolygonalItem::drawShape ( <a href="ntqpainter.html">TQPainter</a> & p )<tt> [pure virtual protected]</tt> +</h3> + +<p> Subclasses must reimplement this function to draw their shape. The +pen and brush of <em>p</em> are already set to <a href="#pen">pen</a>() and <a href="#brush">brush</a>() prior +to calling this function. +<p> <b>Warning:</b> When you reimplement this function, make sure that you +leave the painter in the same state as you found it. For example, +if you start by calling <a href="ntqpainter.html#translate">TQPainter::translate</a>(50, 50), end your +code by calling TQPainter::translate(-50, -50). Be also aware that +the painter might already have some transformations set (i.e., +don't call <a href="ntqpainter.html#resetXForm">TQPainter::resetXForm</a>() when you're done). +<p> <p>See also <a href="#draw">draw</a>(). + +<p>Reimplemented in <a href="tqcanvasrectangle.html#drawShape">TQCanvasRectangle</a>, <a href="tqcanvaspolygon.html#drawShape">TQCanvasPolygon</a>, and <a href="tqcanvasellipse.html#drawShape">TQCanvasEllipse</a>. +<h3 class=fn>void <a name="invalidate"></a>TQCanvasPolygonalItem::invalidate ()<tt> [protected]</tt> +</h3> +Invalidates all information about the area covered by the canvas +item. The item will be updated automatically on the next call that +changes the item's status, for example, <a href="tqcanvasitem.html#move">move</a>() or <a href="tqcanvasitem.html#update">update</a>(). Call +this function if you are going to change the shape of the item (as +returned by <a href="#areaPoints">areaPoints</a>()) while the item is visible. + +<h3 class=fn>bool <a name="isValid"></a>TQCanvasPolygonalItem::isValid () const<tt> [protected]</tt> +</h3> + +<p> Returns TRUE if the polygonal item's area information has not been +invalidated; otherwise returns FALSE. +<p> <p>See also <a href="#invalidate">invalidate</a>(). + +<h3 class=fn><a href="ntqpen.html">TQPen</a> <a name="pen"></a>TQCanvasPolygonalItem::pen () const +</h3> + +<p> Returns the <a href="ntqpen.html">TQPen</a> used to draw the outline of the item, if any. +<p> <p>See also <a href="#setPen">setPen</a>(). + +<h3 class=fn>int <a name="rtti"></a>TQCanvasPolygonalItem::rtti () const<tt> [virtual]</tt> +</h3> +Returns 2 (TQCanvasItem::Rtti_PolygonalItem). +<p> <p>See also <a href="tqcanvasitem.html#rtti">TQCanvasItem::rtti</a>(). + +<p>Reimplemented from <a href="tqcanvasitem.html#rtti">TQCanvasItem</a>. +<p>Reimplemented in <a href="tqcanvasrectangle.html#rtti">TQCanvasRectangle</a>, <a href="tqcanvaspolygon.html#rtti">TQCanvasPolygon</a>, <a href="tqcanvasline.html#rtti">TQCanvasLine</a>, and <a href="tqcanvasellipse.html#rtti">TQCanvasEllipse</a>. +<h3 class=fn>void <a name="setBrush"></a>TQCanvasPolygonalItem::setBrush ( <a href="ntqbrush.html">TQBrush</a> b )<tt> [virtual]</tt> +</h3> +Sets the <a href="ntqbrush.html">TQBrush</a> used when drawing the polygonal item to the brush <em>b</em>. +<p> <p>See also <a href="#setPen">setPen</a>(), <a href="#brush">brush</a>(), and <a href="#drawShape">drawShape</a>(). + +<p>Examples: <a href="canvas-example.html#x2923">canvas/canvas.cpp</a> and <a href="tutorial2-06.html#x2572">chart/chartform_canvas.cpp</a>. +<h3 class=fn>void <a name="setPen"></a>TQCanvasPolygonalItem::setPen ( <a href="ntqpen.html">TQPen</a> p )<tt> [virtual]</tt> +</h3> +Sets the <a href="ntqpen.html">TQPen</a> used when drawing the item to the pen <em>p</em>. +Note that many TQCanvasPolygonalItems do not use the pen value. +<p> <p>See also <a href="#setBrush">setBrush</a>(), <a href="#pen">pen</a>(), and <a href="#drawShape">drawShape</a>(). + +<p>Examples: <a href="canvas-example.html#x2924">canvas/canvas.cpp</a> and <a href="tutorial2-06.html#x2573">chart/chartform_canvas.cpp</a>. +<h3 class=fn>void <a name="setWinding"></a>TQCanvasPolygonalItem::setWinding ( bool enable )<tt> [protected]</tt> +</h3> +If <em>enable</em> is TRUE, the polygonal item will use the winding +algorithm to determine the "inside" of the polygon; otherwise the +odd-even algorithm will be used. +<p> The default is to use the odd-even algorithm. +<p> <p>See also <a href="#winding">winding</a>(). + +<h3 class=fn>bool <a name="winding"></a>TQCanvasPolygonalItem::winding () const<tt> [protected]</tt> +</h3> +Returns TRUE if the polygonal item uses the winding algorithm to +determine the "inside" of the polygon. Returns FALSE if it uses +the odd-even algorithm. +<p> The default is to use the odd-even algorithm. +<p> <p>See also <a href="#setWinding">setWinding</a>(). + +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">TQt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center> +<table width=100% cellspacing=0 border=0><tr> +<td>Copyright © 2007 +<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a> +<td align=right><div align=right>TQt 3.3.8</div> +</table></div></address></body> +</html> |