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I am working on making a simple drawing program. So far I am able to stroke the path with a given color and that all works out fine. I was wondering if there was a way to stroke it with a texture instead of a color. Say for instance I want to give the path the look of a pencil line. Any idea on how I would go about doing that?

Thanks in advance for your help!

Ron Dear
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1 Answers1

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  1. Begin a transparency layer.
  2. Get the path's bounds.
  3. Stroke the path with any non-transparent color.
  4. Set the blend mode to source in.
  5. Fill the bounding rectangle from step 2 with the desired texture pattern.
  6. End the transparency layer.
Peter Hosey
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  • This method worked great after followed the links you provided. Thanks a lot. Even though this did work, however, it is very slow and causes the iPhone only to trigger touches moved infrequently, which provided for an image that is jagged and not smooth. Any idea what I could do to speed it up? – Ron Dear Mar 22 '10 at 13:47
  • Profile it using Instruments. Don't forget to include the UI Recorder instrument (if that works on iPhone apps); with that, you should be able to work out where your time consumption is in relation to events. – Peter Hosey Mar 22 '10 at 14:00
  • Fantastic information. Thanks so much. Let me apply a gradient to a stroked line. Worked great. – PyjamaSam Mar 26 '10 at 23:38
  • @PeterHosey I am having [issue](http://stackoverflow.com/questions/22880587/textured-line-in-cg) with this method. – Blind Ninja Apr 05 '14 at 12:14