[type] Add HBFixed template

This commit is contained in:
Behdad Esfahbod 2022-10-13 12:12:24 -06:00
parent 8c29dcaee4
commit 5769d422c5
1 changed files with 13 additions and 16 deletions

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@ -141,27 +141,24 @@ typedef HBINT32 FWORD32;
/* 16-bit unsigned integer (HBUINT16) that describes a quantity in FUnits. */ /* 16-bit unsigned integer (HBUINT16) that describes a quantity in FUnits. */
typedef HBUINT16 UFWORD; typedef HBUINT16 UFWORD;
/* 16-bit signed fixed number with the low 14 bits of fraction (2.14). */ template <typename Type, unsigned fraction_bits>
struct F2DOT14 : HBINT16 struct HBFixed : Type
{ {
F2DOT14& operator = (uint16_t i ) { HBINT16::operator= (i); return *this; } static constexpr float shift = (float) (1 << fraction_bits);
// 16384 means 1<<14 static_assert (Type::static_size * 8 > fraction_bits, "");
float to_float () const { return ((int32_t) v) / 16384.f; }
void set_float (float f) { v = roundf (f * 16384.f); } HBFixed& operator = (typename Type::type i ) { Type::operator= (i); return *this; }
float to_float () const { return ((int32_t) Type::v) / shift; }
void set_float (float f) { Type::v = roundf (f * shift); }
public: public:
DEFINE_SIZE_STATIC (2); DEFINE_SIZE_STATIC (Type::static_size);
}; };
/* 16-bit signed fixed number with the low 14 bits of fraction (2.14). */
using F2DOT14 = HBFixed<HBINT16, 14>;
/* 32-bit signed fixed-point number (16.16). */ /* 32-bit signed fixed-point number (16.16). */
struct F16DOT16 : HBINT32 using F16DOT16 = HBFixed<HBINT32, 16>;
{
F16DOT16& operator = (uint32_t i) { HBINT32::operator= (i); return *this; }
// 65536 means 1<<16
float to_float () const { return ((int32_t) v) / 65536.f; }
void set_float (float f) { v = roundf (f * 65536.f); }
public:
DEFINE_SIZE_STATIC (4);
};
/* Date represented in number of seconds since 12:00 midnight, January 1, /* Date represented in number of seconds since 12:00 midnight, January 1,
* 1904. The value is represented as a signed 64-bit integer. */ * 1904. The value is represented as a signed 64-bit integer. */