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Optimized packing and unpacking functions

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This commit is contained in:
Christophe Riccio 2013-09-08 17:56:18 +02:00
parent 804078f690
commit cd186dadb3
4 changed files with 35 additions and 128 deletions
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145
glm/core/func_packing.inl
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@ -30,169 +30,80 @@ namespace glm
{
GLM_FUNC_QUALIFIER uint32 packUnorm2x16(vec2 const & v)
{
uint16 A(uint16(round(clamp(v.x, 0.0f, 1.0f) * 65535.0f)));
uint16 B(uint16(round(clamp(v.y, 0.0f, 1.0f) * 65535.0f)));
return uint32((B << 16) | A);
u16vec2 Topack(round(clamp(v, 0.0f, 1.0f) * 65535.0f));
return *reinterpret_cast<uint32*>(&Topack);
}
GLM_FUNC_QUALIFIER vec2 unpackUnorm2x16(uint32 const & p)
{
uint32 Mask16((1 << 16) - 1);
uint32 A((p >> 0) & Mask16);
uint32 B((p >> 16) & Mask16);
return vec2(A, B) * float(1.5259021896696421759365224689097e-5); // 1.0 / 65535.0
vec2 Unpack(*reinterpret_cast<u16vec2*>(const_cast<uint32*>(&p)));
return Unpack * float(1.5259021896696421759365224689097e-5); // 1.0 / 65535.0
}
GLM_FUNC_QUALIFIER uint32 packSnorm2x16(vec2 const & v)
{
i16vec2 Unpack(round(clamp(v ,-1.0f, 1.0f) * 32767.0f));
u32vec2 Topack(*reinterpret_cast<u16vec2*>(&Unpack));
return (Topack.y << 16) | (Topack.x << 0);
i16vec2 Topack(round(clamp(v ,-1.0f, 1.0f) * 32767.0f));
return *reinterpret_cast<uint32*>(&Topack);
}
GLM_FUNC_QUALIFIER vec2 unpackSnorm2x16(uint32 const & p)
{
union iu
{
int16 i;
uint16 u;
} A, B;
uint32 Mask16((1 << 16) - 1);
A.u = uint16((p >> 0) & Mask16);
B.u = uint16((p >> 16) & Mask16);
glm::vec2 Pack(A.i, B.i);
return clamp(Pack * 1.0f / 32767.0f, -1.0f, 1.0f);
vec2 Unpack(*reinterpret_cast<i16vec2*>(const_cast<uint32*>(&p)));
return clamp(Unpack * 1.0f / 32767.0f, -1.0f, 1.0f);
}
GLM_FUNC_QUALIFIER uint32 packUnorm4x8(vec4 const & v)
{
uint8 A((uint8)round(clamp(v.x, 0.0f, 1.0f) * 255.0f));
uint8 B((uint8)round(clamp(v.y, 0.0f, 1.0f) * 255.0f));
uint8 C((uint8)round(clamp(v.z, 0.0f, 1.0f) * 255.0f));
uint8 D((uint8)round(clamp(v.w, 0.0f, 1.0f) * 255.0f));
return uint32((D << 24) | (C << 16) | (B << 8) | A);
glm::u8vec4 Topack(round(clamp(v, 0.0f, 1.0f) * 255.0f));
return *reinterpret_cast<uint32*>(&Topack);
}
GLM_FUNC_QUALIFIER vec4 unpackUnorm4x8(uint32 const & p)
{
uint32 Mask8((1 << 8) - 1);
uint32 A((p >> 0) & Mask8);
uint32 B((p >> 8) & Mask8);
uint32 C((p >> 16) & Mask8);
uint32 D((p >> 24) & Mask8);
return glm::vec4(
A * 1.0f / 255.0f,
B * 1.0f / 255.0f,
C * 1.0f / 255.0f,
D * 1.0f / 255.0f);
glm::vec4 Unpack(*reinterpret_cast<glm::u8vec4*>(const_cast<uint32*>(&p)));
return Unpack * 0.003921568627451f; // 1 / 255
}
GLM_FUNC_QUALIFIER uint32 packSnorm4x8(vec4 const & v)
{
union iu
{
int8 i;
uint8 u;
} A, B, C, D;
glm::vec4 Unpack = clamp(v,-1.0f, 1.0f) * 127.0f;
A.i = int8(round(Unpack.x));
B.i = int8(round(Unpack.y));
C.i = int8(round(Unpack.z));
D.i = int8(round(Unpack.w));
uint32 Pack = (uint32(D.u) << 24) | (uint32(C.u) << 16) | (uint32(B.u) << 8) | (uint32(A.u) << 0);
return Pack;
glm::i8vec4 Topack(round(clamp(v ,-1.0f, 1.0f) * 127.0f));
return *reinterpret_cast<uint32*>(&Topack);
}
GLM_FUNC_QUALIFIER glm::vec4 unpackSnorm4x8(uint32 const & p)
{
union iu
{
int8 i;
uint8 u;
} A, B, C, D;
uint32 Mask8((1 << 8) - 1);
A.u = uint8((p >> 0) & Mask8);
B.u = uint8((p >> 8) & Mask8);
C.u = uint8((p >> 16) & Mask8);
D.u = uint8((p >> 24) & Mask8);
glm::vec4 Pack(A.i, B.i, C.i, D.i);
return clamp(Pack * 1.0f / 127.0f, -1.0f, 1.0f);
glm::vec4 Unpack(*reinterpret_cast<glm::i8vec4*>(const_cast<uint32*>(&p)));
return clamp(
Unpack * 0.0078740157480315f, // 1.0f / 127.0f
-1.0f, 1.0f);
}
GLM_FUNC_QUALIFIER double packDouble2x32(uvec2 const & v)
{
struct uint32_pair
{
uint32 x;
uint32 y;
};
union helper
{
uint32_pair input;
double output;
} Helper;
Helper.input.x = v.x;
Helper.input.y = v.y;
return Helper.output;
//return *(double*)&v;
return *reinterpret_cast<double*>(const_cast<uvec2*>(&v));
}
GLM_FUNC_QUALIFIER uvec2 unpackDouble2x32(double const & v)
{
struct uint32_pair
{
uint32 x;
uint32 y;
};
union helper
{
double input;
uint32_pair output;
} Helper;
Helper.input = v;
return uvec2(Helper.output.x, Helper.output.y);
return *reinterpret_cast<uvec2*>(const_cast<double*>(&v));
}
GLM_FUNC_QUALIFIER uint packHalf2x16(vec2 const & v)
{
union helper
{
uint other;
struct
{
detail::hdata a, b;
} orig;
} Pack;
i16vec2 Unpack(
detail::toFloat16(v.x),
detail::toFloat16(v.y));
Pack.orig.a = detail::toFloat16(v.x);
Pack.orig.b = detail::toFloat16(v.y);
return Pack.other;
return *reinterpret_cast<uint*>(&Unpack);
}
GLM_FUNC_QUALIFIER vec2 unpackHalf2x16(uint const & v)
{
union helper
{
uint other;
struct
{
detail::hdata a, b;
} orig;
} Unpack;
Unpack.other = v;
i16vec2 Unpack = *reinterpret_cast<i16vec2*>(const_cast<uint*>(&v));
return vec2(detail::toFloat32(Unpack.orig.a), detail::toFloat32(Unpack.orig.b));
return vec2(
detail::toFloat32(Unpack.x),
detail::toFloat32(Unpack.y));
}
}//namespace glm

1
readme.txt
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@ -56,6 +56,7 @@ GLM 0.9.5.0: 2013-XX-XX
- Uses C++ casts
- Fixed .length() that should return a int and not a size_t
- Removed unnecessary conversions
- Optimized packing and unpacking functions
================================================================================
GLM 0.9.4.6: 2013-08-XX

7
test/core/core_func_packing.cpp
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@ -41,12 +41,7 @@ int test_packUnorm2x16()
int test_packSnorm2x16()
{
int Error = 0;
/*
std::vector<glm::hvec2> A;
A.push_back(glm::hvec2(glm::half( 1.0f), glm::half( 0.0f)));
A.push_back(glm::hvec2(glm::half(-0.5f), glm::half(-0.7f)));
A.push_back(glm::hvec2(glm::half(-0.1f), glm::half( 0.1f)));
*/
std::vector<glm::vec2> A;
A.push_back(glm::vec2( 1.0f, 0.0f));
A.push_back(glm::vec2(-0.5f,-0.7f));