Is anyone aware of a sensor fusion implementation that uses only integer operations instead of all the floating point accumulates/divides/multiplies in most open source implementations?
On my processor performing repeated floating point calculations are expensive and I want to reduce them as much as possible. I might lose some precision but my application does not require a highly precise output.
Is there any issue turning all the variables to ints and just taking the hit in precision? Any advice would be great, thanks all.
The use of fixed-point is the best solution for flexible maths operations on a device with no FPU.
Anthony Williams' fixed point maths library would suit, it uses a 64 bit integer type to provide a 34Q28 (34 integer bits, 28 fractional bit) format floating point type with extensive maths, operator and conversion functions. It is written in C++ to create a fixed type as a class, with extensive operator overloading and standard maths functions so that it is largely inter-changeable with float or double in existing code.
I realise the the question is tagged C but you need not use C++ syntax extensively, just compile your C code as C++, include the fixed.hpp header, replace float or double with fixed and compile/link the fixed.cpp file with your project.