I have a dataset of around 85k road segments and 130k non-road segments where I want to cut off small parts of the roads around the non-road segments: There's a buffer around each of the non-road segments that I use as clipper on the roads.
I've applied all the tips given in this thread ( https://knowledge.safe.com/questions/62461/why-the-clipper-transformer-is-too-slow.html ). I forced the clipper to wait until all clippers were available, I dissolved both datasets before clipping and it works fine on smaller datasets. Still, it takes around 2 seconds per feature in the dissolved dataset (total 12k). I've even discarded all attributes.
Algorithmically, clipping polygons should take nowhere near as long when everything fits in memory. [M. de Berg et al. Computational Geometry. Ch2 ]
Is there anything I've missed? Why is clipping so slow?
