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25 lines
947 B
HTML
25 lines
947 B
HTML
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<html>
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<center>
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<h2>Vector deformation</h2>
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</center>
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<p>This demo shows how to use advanced vector techniques to draw text
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using a <code>QPainterPath</code>.</p>
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<p>We define a vector deformation field in the shape of a lens and apply
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this to all points in a path. This means that what is rendered on
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screen is not pixel manipulation, but modified vector representations of
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the glyphs themselves. This is visible from the high quality of the
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antialiased edges for the deformed glyphs.</p>
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<p>To get a fairly complex path we allow the user to type in text and
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convert the text to paths. This is done using the
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<code>QPainterPath::addText()</code> function.</p>
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<p>The lens is drawn using a single call to <code>drawEllipse()</code>, using
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a <code>QRadialGradient</code> to fill it with a specialized color table,
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giving the effect of the Sun's reflection and a drop shadow. The lens
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is cached as a pixmap for better performance.</p>
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</html>
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