[OSGeo-Discuss] PerfectTIN 0.4.0rc2 released. Anyone know GPU programming?

[Pierre Abbat]

Last weekend I was visiting Pat, the surveyor who asked me to write 
PerfectTIN, and he gave me a 56 Mpoint cloud of some site. I ran 0.4.0rc1 on 
it and found some bugs that showed up when processing a point cloud that big, 
which I fixed. (The largest cloud I'd run it on before has 13 million points.) 
He showed me the spikes when an earlier version processed it and verified that 
0.4.0rc1 does not produce spikes. I just released 0.4.0rc2 with the bugs fixed.

The reason I'm not calling this 0.4.0 is that twice, once each on two different 
computers, the program crashed, but did not dump core because of ulimit. I ran 
the debugger, but could not get it to crash again. I ran it without the 
debugger, but it still didn't crash. Could you run it in the debugger and see 
if it crashes? https://github.com/phma/perfecttin

I'm planning to implement speed improvement for 0.5.0. When it starts 
processing a point cloud, each of the six triangles has a huge number of dots, 
and it can't use more than one thread, because it has to lock all the 
triangles, since they share a corner. So I'm going to partition the work into 
tasks of about 65536 dots each and let any thread that would otherwise be 
sleeping work on a task. Later I'd like to have the GPU, if present, process 
tasks, but I don't know how. Do any of you know how to use OpenCL to write GPU 
code?

Pierre
-- 
Por H o por B, los campos magnéticos se difieren dentro de un imán.