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| 31 | </td>
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| 32 | <td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>Canvas Module</h1>
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| 33 |
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| 34 |
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| 35 |
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| 36 | <p>
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| 37 | <p> The canvas module provides a highly optimized 2D graphic area called
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| 38 | <a href="qcanvas.html">QCanvas</a>. The canvas can contain an arbitrary number of <a href="qcanvasitem.html">QCanvasItems</a>. Canvas items can have an arbitrary
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| 39 | shape, size and content, can be freely moved around in the canvas,
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| 40 | and can be checked for collisions. Canvas items can be set to move
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| 41 | across the canvas automatically and animated canvas items are
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| 42 | supported with <a href="qcanvassprite.html">QCanvasSprite</a>. (If you require 3D graphics see Qt's
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| 43 | <a href="opengl.html">OpenGL module</a>.)
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| 44 | <p> The canvas module uses a document/view model. The <a href="qcanvasview.html">QCanvasView</a> class
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| 45 | is used to show a particular view of a canvas. Multiple views can operate
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| 46 | on the same canvas at the same time. Every view can use an arbitrary
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| 47 | <a href="qwmatrix.html#TransformationMode">transformation matrix</a> on the canvas which makes it easy to implement
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| 48 | features such as zooming.
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| 49 | <p> <center><a href="qcanvas.html">
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| 50 | <img src="qcanvas.png" alt="Screenshot of a canvas"></a></center>
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| 51 | <p> Qt provides a number of predefined <a href="qcanvas.html">QCanvas</a> items as listed below.
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| 52 | <p> <ul>
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| 53 | <li> <a href="qcanvasitem.html">QCanvasItem</a> -- An abstract base class for all canvas items.
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| 54 | <li> <a href="qcanvasellipse.html">QCanvasEllipse</a> -- An ellipse or "pie segment".
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| 55 | <li> <a href="qcanvasline.html">QCanvasLine</a> -- A line segment.
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| 56 | <li> <a href="qcanvaspolygon.html">QCanvasPolygon</a> -- A polygon.
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| 57 | <li> <a href="qcanvaspolygonalitem.html">QCanvasPolygonalItem</a> -- A base class for items that have a
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| 58 | non-rectangular shape. Most canvas items derive from this class.
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| 59 | <li> <a href="qcanvasrectangle.html">QCanvasRectangle</a> -- A rectangle. The rectangle cannot be tilted or
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| 60 | rotated. Rotated rectangles can be drawn using QCanvasPolygon.
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| 61 | <li> <a href="qcanvasspline.html">QCanvasSpline</a> -- A multi-bezier spline.
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| 62 | <li> <a href="qcanvassprite.html">QCanvasSprite</a> -- An animated pixmap.
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| 63 | <li> <a href="qcanvastext.html">QCanvasText</a> -- A text string.
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| 64 | </ul>
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| 65 | <p> The two classes <a href="qcanvaspixmap.html">QCanvasPixmap</a> and <a href="qcanvaspixmaparray.html">QCanvasPixmapArray</a> are used
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| 66 | by <a href="qcanvassprite.html">QCanvasSprite</a> to show animated and moving pixmaps on the
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| 67 | canvas.
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| 68 | <p> More specialized items can be created by inheriting from one of the
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| 69 | canvas item classes. It is easiest to inherit from one of
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| 70 | <a href="qcanvasitem.html">QCanvasItem</a>'s derived classes (usually <a href="qcanvaspolygonalitem.html">QCanvasPolygonalItem</a>) rather
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| 71 | than inherit QCanvasItem directly.
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| 72 | <p> See <tt>examples/canvas</tt> for an example that shows off some of <a href="qcanvas.html">QCanvas</a>'s
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| 73 | capabilities.
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| 74 | <p>
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| 75 | <!-- eof -->
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| 76 | <p><address><hr><div align=center>
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| 77 | <table width=100% cellspacing=0 border=0><tr>
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| 78 | <td>Copyright © 2007
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| 79 | <a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a>
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| 80 | <td align=right><div align=right>Qt 3.3.8</div>
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| 81 | </table></div></address></body>
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| 82 | </html>
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