PDF To HTML5 Conversion – Vector Graphics
By Mark Stephens
Expert Author
Article Date: 2011-06-23
Vector Graphics are very easy to use in HTML5 and easy to translate from a Java or a PDF scenario.
First off, you need a drawing surface (rather like a Graphics2D object in Java). This is the context and it is created in Javascript as follows in your HTML code.<body onload="draw();">
<!- Canvas we draw the content onto -><canvas id="pdf" width="612.0″ height="792.0″ />
</body> The actual drawing is done in the draw() method using a set of primitives very similar to Java/PDF commands. Here is an excerpt.
<script type="application/javascript">function draw(){
var pdf_canvas=document.getElementById("pdf");
var pdf_context=pdf_canvas.getContext("2d");
pdf_context.fillStyle="rgb(0, 0, 0)";
pdf_context.beginPath();
pdf_context.moveTo(206,288);
pdf_context.bezierCurveTo(208,289,220,291,222,288);
pdf_context.bezierCurveTo(225,286,222,278,216,273);
pdf_context.closePath();The hardest thing from a PDF perspective is the lack of non-RGB colorspaces which means the color values need to be pre-converted. Shape conversion works pretty well as these 2 examples show - click on the images to open the HTML.
Click here to see all the article in the PDF to HTML5 conversion series.
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About the Author:
Mark Stephens runs IDRsolutions, developing the JPedal PDF library in Java, and shares his thoughts on Java, PDF, the Business of Software and Mediaeval History at http://www.jpedal.org/PDFblog .
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