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These functions operate on 32-bit numbers, fix16_t, which have 16 bit integer part and 16 bit fractional part.

License: MIT License

C# 100.00%

libfixmath.net's Introduction

libfixmath.net

origin : https://code.google.com/archive/p/libfixmath/

fix16

using fix16_t = System.Int32;

public struct fix16
{
  private fix16_t value;
}

32-bit numbers, fix16_t, which have 16 bit integer part and 16 bit fractional part.
max : 32767.999_985
min : -32768.0
- The minimum value is also used to represent fix16_overflow for overflow detection, so for some operations it cannot be determined whether it overflowed or the result was the smallest possible value. In practice this does not matter much.
The smallest unit (machine precision) of the datatype is 1/65536 = 0.000_015

wiki

https://code.google.com/archive/p/libfixmath/wikis/FunctionReference.wiki

Define Option

I already removed FIXMATH_NO_64BIT, FIXMATH_OPTIMIZE_8BIT from origin source.

Accuracy

    FIXMATH_NO_ROUNDING: Disable rounding. Results may round randomly up or down, i.e. their accuracy is +-1. Runs slightly faster.
    FIXMATH_NO_OVERFLOW: Disable overflow detection and saturating arithmetic support. Overflowing computations will give garbage results. Runs slightly faster.

Platform

    FIXMATH_NO_CACHE: Do not use cache for exp etc. function results. Uses less RAM, runs slightly slower.

Algorithms

    FIXMATH_SIN_LUT: This uses a look-up table generated by the fixsingen tool from svn, it is faster on some devices but the lookup table takes up ~200KiB (205376 bytes) in memory and can be slower dependant on usage.
    FIXMATH_FAST_SIN: This enables a faster but less accurate approximation of the sin function, for code where accuracy isn't as important such as games logic or graphics rendering then this is often a worthwhile tradeoff.