LIB_EXPORT int16_t GFX_SineCosineGet(
    int16_t v, 
    GFX_TRIG_FUNCTION_TYPE type
);

int16_t - result of sine cosine fixed point value (times 256), calling function needs to divide by 256 to get good result 

ex. "a * cos(v)" would be "a * GFX_SineCosineGet(v, GFX_TRIG_COSINE_TYPE) / 256";