Converting strokes to filled paths - IStrokerTransform

📌 Overview

Different rendering engines have different stroking abilities. XPS for example supports several stroking capabilities that PDF or SVG support, such as triangular line caps, using different start and end line caps, and the ability to mark sections of a path as non-stroking.

Further, XPS and most other renderers differ in how miters are treated, with XPS “clipping” miters to the miter limit where PDF and SVG renderers would simply bevel instead.

📗 Instructions

The IStrokerTransform filter provides a method for converting strokes to plain fills in all cases or only in certain circumstances, with the aim of modifying content so that it is reliably reproduced when subject to third-party conversion or rendering.

🪜 Steps

Create the transform: Simply use IStrokerTransform::create().
Apply settings if needed: For example you may want to set the following depending on your use case.

CPP

strokerTransform->setupForPDFStyleOutput();
strokerTransform->setConvertAllStrokes(true);

Apply the transform to the page: Simply use strokerTransform->transformPage(page);

⌨️ Code Examples

Two examples are reproduced here in C++ and C#. You can also find them on our GitHub Gists page. See StrokerTransform.cpp, StrokerTransform.cs.

C++

C#

CPP

const auto page = document->getPage(0);

// Apply stroker transform to convert strokes to filled paths
const auto strokerTransform = IStrokerTransform::create(mako);
strokerTransform->setupForPDFStyleOutput();
strokerTransform->setConvertAllStrokes(true);
strokerTransform->transformPage(page);

C#

using var page = assembly.getDocument().getPage();

// Apply stroker transform to convert strokes to filled paths
using var strokerTransform = IStrokerTransform.create(mako);
strokerTransform.setupForPDFStyleOutput();
strokerTransform.setConvertAllStrokes(true);
strokerTransform.transformPage(page);

☑️ Conclusion

The IStrokerTransform filter is an essential tool for converting strokes to filled paths, ensuring consistent rendering across different platforms. By following the outlined steps and utilizing the provided code examples, users can effectively manage and transform stroke data for reliable reproduction.

📚 Additional Resources

If you need additional help, see our API documentation for detailed information on class/method usage, or raise a support ticket via our customer portal.