Fastmath changes broke AngleBetween

jdelauney / SIMD-VectorMath-UnitTest

For testing asm SIMD (SSE/SSE 2/SSE 3/SSE 4.x / AVX /AVX 2) vector math library (2f, 4f, matrix, quaternion...) with Lazarus and FreePascal Compiler

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Fastmath changes broke AngleBetween #18

Closed dicepd closed 6 years ago

dicepd commented 6 years ago

As above

jdelauney commented 6 years ago

Ok i'm correcting the function, it's ok now. I push the code tonight after my job

jdelauney commented 6 years ago

I found a realy cool link https://web.archive.org/web/20161219143458/http://http.developer.nvidia.com/Cg/index_stdlib.html for implement Step, Saturate, SmoothStep, FaceForward....

dicepd commented 6 years ago

It seems that fastmath can reduce precision, should we reflect this in the tests by ifdef USE_FASTMATH and put two epsilon values to pass at the available precision for the mode. It will at least be some sort of reference/documentation to where precision is reduced through fastmath.

jdelauney commented 6 years ago

Yes Fastmath reduce precision we do approximation. A correct minimum precision for me wil be 1e-4 with a range error max of 0.0003. Put two epsilon values it will a good thing for having a correct evaluation.