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1 <html>
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2 <center>
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3 <h2>Vector deformation</h2>
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4 </center>
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5
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6 <p>This demo shows how to use advanced vector techniques to draw text
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7 using a <code>QPainterPath</code>.</p>
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8
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9 <p>We define a vector deformation field in the shape of a lens and apply
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10 this to all points in a path. This means that what is rendered on
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11 screen is not pixel manipulation, but modified vector representations of
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12 the glyphs themselves. This is visible from the high quality of the
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13 antialiased edges for the deformed glyphs.</p>
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14
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15 <p>To get a fairly complex path we allow the user to type in text and
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16 convert the text to paths. This is done using the
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17 <code>QPainterPath::addText()</code> function.</p>
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18
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19 <p>The lens is drawn using a single call to <code>drawEllipse()</code>, using
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20 a <code>QRadialGradient</code> to fill it with a specialized color table,
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21 giving the effect of the Sun's reflection and a drop shadow. The lens
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22 is cached as a pixmap for better performance.</p>
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23
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24 </html>
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