Fix simulation consistency and memory leaks #35
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Thanks for PR, can you have a look at linthub and see about addressing those issues? As for the rest.. it seems we lost python 2.6 support. |
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I changed the C-style casts. The other linthub complaints are about lines of code which I didn't touch. |
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Great, thank you. :) |
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Found a very similar precision issue with sin and cos on Apple's version of Clang. I could make the code a little nicer by creating wrapper functions instead of macros, but I'm pretty sure that doing the calculation at double precision is the best way to fix this problem after all. |
ftomassetti
reviewed
Sep 30, 2016
| @@ -44,6 +44,9 @@ uint32_t Segments::area() | |||
| void Segments::reset() | |||
| { | |||
| memset(segment, -1, sizeof(uint32_t) * _area); | |||
| for (int i = 0; i<seg_data.size(); i++) { | |||
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Linthub is suggesting to put spaces around the < operator
pkdawson
changed the title
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I was getting wildly different simulation results with Visual C++, using the same seed/parameters that I was using on Linux or OS X. Most of that was caused by the fact that
sizeof(long)is 4, as opposed to 8 on Clang, GCC, etc.float kc = (seed*seed) % 256;On this line in particular, the signed 32-bit integer would often overflow into the negatives. Making it explicitly 64-bit keeps behavior consistent across platforms.
That mostly fixes it, but I was still seeing subtle inconsistencies. This is harder to explain. For some reason,
sinfyields different results when MSVC (2013 or 2015) produces a 64-bit binary. For example, with floats expressed as their raw bytes:sinf(5.516943f)=0xbf3184cdon GCC, Clang, and MSVC x86sinf(5.516943f)=0xbf3184ceon MSVC x86-64Tried adjusting some flags, but it didn't help. Using the double version of
sinand then casting back to float gets the correct results. This solution is a little ugly, but it's the only thing that worked.