Better type punning

This commit is contained in:
Deukhoofd 2022-02-11 14:06:52 +01:00
parent c239ac5220
commit c1aea15254
Signed by: Deukhoofd
GPG Key ID: F63E044490819F6F
1 changed files with 24 additions and 6 deletions

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@ -72,27 +72,45 @@ double fraction(double v)
} }
#endif #endif
template<typename T, typename F>
struct alias_cast_t
{
union
{
F raw;
T data;
};
};
// As AngelScript doesn't allow bitwise manipulation of float types we'll provide a couple of // As AngelScript doesn't allow bitwise manipulation of float types we'll provide a couple of
// functions for converting float values to IEEE 754 formatted values etc. This also allow us to // functions for converting float values to IEEE 754 formatted values etc. This also allow us to
// provide a platform agnostic representation to the script so the scripts don't have to worry // provide a platform agnostic representation to the script so the scripts don't have to worry
// about whether the CPU uses IEEE 754 floats or some other representation // about whether the CPU uses IEEE 754 floats or some other representation
float fpFromIEEE(asUINT raw) float fpFromIEEE(asUINT raw)
{ {
// TODO: Identify CPU family to provide proper conversion // TODO: Identify CPU family to provide proper conversion
// if the CPU doesn't natively use IEEE style floats // if the CPU doesn't natively use IEEE style floats
return *reinterpret_cast<float*>(&raw); alias_cast_t<asUINT, float> t;
t.raw = raw;
return t.data;
} }
asUINT fpToIEEE(float fp) asUINT fpToIEEE(float fp)
{ {
return *reinterpret_cast<asUINT*>(&fp); alias_cast_t<float, asUINT> t;
t.raw = fp;
return t.data;
} }
double fpFromIEEE(asQWORD raw) double fpFromIEEE(asQWORD raw)
{ {
return *reinterpret_cast<double*>(&raw); alias_cast_t<asQWORD, double> t;
t.raw = raw;
return t.data;
} }
asQWORD fpToIEEE(double fp) asQWORD fpToIEEE(double fp)
{ {
return *reinterpret_cast<asQWORD*>(&fp); alias_cast_t<double, asQWORD> t;
t.raw = fp;
return t.data;
} }
// closeTo() is used to determine if the binary representation of two numbers are // closeTo() is used to determine if the binary representation of two numbers are