Hello<br><br><div>I am that Eugenpaul doing vector layer generalization. Happy</div><div>to be accepted, but it is also quite a responsibility, so I am </div><div>feeling a very special mix of emotions right now. You may </div>
<div>remember my proposal, but the work plan has been changed </div><div>a bit, so I will briefly tell you what I have decided to do after </div><div>several conversations with my mentor, Alexander Bruy. <br></div><div>1. My first aim now is to implement generalization for a </div>
<div>collection of objects keeping their topological relations. </div><div>Current implementation handles only one feature and avoids </div><div>new intersections as a result of generalization. I'll take its </div><div>
base algorithm, the Douglas-Peucker, and add tracking of </div><div>connected edges of the neighboring objects. <br></div><div>2. Then I will implement the on-the-fly generalization to </div><div>speed up rendering. According to some tests done by </div>
<div>Alexander [0], a simple distance threshold routine followed by </div><div>the Douglas-Peucker algorithm shows significant reduction </div><div>of the rendering time, especially with complex style lines. <br></div><div>
3. Then I will look into the render cache realization. It is the </div><div>right way of speeding up rendering, maybe there is a way to </div><div>improve it. <br></div><div>4. At last, if I will have enough time, I'll try to adapt existing </div>
<div>feature cache patch to the last QGIS version.<br></div><div>Everything is planned to be supported by unit tests. </div><div>All the progress will be described in the blog [1]. <br></div><div>If you have any ideas on how to do these things better, </div>
<div>please let me know. <br></div><br>[0] <a href="https://picasaweb.google.com/lh/photo/avPtza_JMMdA5bkcOAr61tBgozyHltVoaaGmEBdHNL4">https://picasaweb.google.com/lh/photo/avPtza_JMMdA5bkcOAr61tBgozyHltVoaaGmEBdHNL4</a><br>
<div> - shows dependence of rendering time on the number of lines </div><div>and their style, "+gen" shows rendering time with on-the-fly</div><div>simplification <br></div>[1] <a href="http://blogs.gis-lab.info/ugnpaul/">http://blogs.gis-lab.info/ugnpaul/</a><br>
<br>Thank you!<br>