341 lines
12 KiB
C++
341 lines
12 KiB
C++
//-------------------------------------------------------------------------------------
|
|
// BC.h
|
|
//
|
|
// Block-compression (BC) functionality
|
|
//
|
|
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
|
|
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
|
|
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
|
|
// PARTICULAR PURPOSE.
|
|
//
|
|
// Copyright (c) Microsoft Corporation. All rights reserved.
|
|
//
|
|
// http://go.microsoft.com/fwlink/?LinkId=248926
|
|
//-------------------------------------------------------------------------------------
|
|
|
|
#pragma once
|
|
|
|
#include <assert.h>
|
|
#include <directxmath.h>
|
|
#include <directxpackedvector.h>
|
|
|
|
namespace DirectX
|
|
{
|
|
//-------------------------------------------------------------------------------------
|
|
// Macros
|
|
//-------------------------------------------------------------------------------------
|
|
|
|
// Because these are used in SAL annotations, they need to remain macros rather than const values
|
|
#define NUM_PIXELS_PER_BLOCK 16
|
|
|
|
//-------------------------------------------------------------------------------------
|
|
// Constants
|
|
//-------------------------------------------------------------------------------------
|
|
|
|
enum BC_FLAGS
|
|
{
|
|
BC_FLAGS_NONE = 0x0,
|
|
BC_FLAGS_DITHER_RGB = 0x10000, // Enables dithering for RGB colors for BC1-3
|
|
BC_FLAGS_DITHER_A = 0x20000, // Enables dithering for Alpha channel for BC1-3
|
|
BC_FLAGS_UNIFORM = 0x40000, // By default, uses perceptual weighting for BC1-3; this flag makes it a uniform weighting
|
|
BC_FLAGS_USE_3SUBSETS = 0x80000, // By default, BC7 skips mode 0 & 2; this flag adds those modes back
|
|
BC_FLAGS_FORCE_BC7_MODE6 = 0x100000, // BC7 should only use mode 6; skip other modes
|
|
};
|
|
|
|
//-------------------------------------------------------------------------------------
|
|
// Structures
|
|
//-------------------------------------------------------------------------------------
|
|
class LDRColorA;
|
|
|
|
class HDRColorA
|
|
{
|
|
public:
|
|
float r, g, b, a;
|
|
|
|
public:
|
|
HDRColorA() = default;
|
|
HDRColorA(float _r, float _g, float _b, float _a) : r(_r), g(_g), b(_b), a(_a) {}
|
|
HDRColorA(const HDRColorA& c) : r(c.r), g(c.g), b(c.b), a(c.a) {}
|
|
|
|
// binary operators
|
|
HDRColorA operator + ( const HDRColorA& c ) const
|
|
{
|
|
return HDRColorA(r + c.r, g + c.g, b + c.b, a + c.a);
|
|
}
|
|
|
|
HDRColorA operator - ( const HDRColorA& c ) const
|
|
{
|
|
return HDRColorA(r - c.r, g - c.g, b - c.b, a - c.a);
|
|
}
|
|
|
|
HDRColorA operator * ( float f ) const
|
|
{
|
|
return HDRColorA(r * f, g * f, b * f, a * f);
|
|
}
|
|
|
|
HDRColorA operator / ( float f ) const
|
|
{
|
|
float fInv = 1.0f / f;
|
|
return HDRColorA(r * fInv, g * fInv, b * fInv, a * fInv);
|
|
}
|
|
|
|
float operator * ( const HDRColorA& c ) const
|
|
{
|
|
return r * c.r + g * c.g + b * c.b + a * c.a;
|
|
}
|
|
|
|
// assignment operators
|
|
HDRColorA& operator += ( const HDRColorA& c )
|
|
{
|
|
r += c.r;
|
|
g += c.g;
|
|
b += c.b;
|
|
a += c.a;
|
|
return *this;
|
|
}
|
|
|
|
HDRColorA& operator -= ( const HDRColorA& c )
|
|
{
|
|
r -= c.r;
|
|
g -= c.g;
|
|
b -= c.b;
|
|
a -= c.a;
|
|
return *this;
|
|
}
|
|
|
|
HDRColorA& operator *= ( float f )
|
|
{
|
|
r *= f;
|
|
g *= f;
|
|
b *= f;
|
|
a *= f;
|
|
return *this;
|
|
}
|
|
|
|
HDRColorA& operator /= ( float f )
|
|
{
|
|
float fInv = 1.0f / f;
|
|
r *= fInv;
|
|
g *= fInv;
|
|
b *= fInv;
|
|
a *= fInv;
|
|
return *this;
|
|
}
|
|
|
|
HDRColorA& Clamp(_In_ float fMin, _In_ float fMax)
|
|
{
|
|
r = std::min<float>(fMax, std::max<float>(fMin, r));
|
|
g = std::min<float>(fMax, std::max<float>(fMin, g));
|
|
b = std::min<float>(fMax, std::max<float>(fMin, b));
|
|
a = std::min<float>(fMax, std::max<float>(fMin, a));
|
|
return *this;
|
|
}
|
|
|
|
HDRColorA(const LDRColorA& c);
|
|
HDRColorA& operator = (const LDRColorA& c);
|
|
LDRColorA ToLDRColorA() const;
|
|
};
|
|
|
|
inline HDRColorA* HDRColorALerp(_Out_ HDRColorA *pOut, _In_ const HDRColorA *pC1, _In_ const HDRColorA *pC2, _In_ float s)
|
|
{
|
|
pOut->r = pC1->r + s * (pC2->r - pC1->r);
|
|
pOut->g = pC1->g + s * (pC2->g - pC1->g);
|
|
pOut->b = pC1->b + s * (pC2->b - pC1->b);
|
|
pOut->a = pC1->a + s * (pC2->a - pC1->a);
|
|
return pOut;
|
|
}
|
|
|
|
#pragma pack(push,1)
|
|
// BC1/DXT1 compression (4 bits per texel)
|
|
struct D3DX_BC1
|
|
{
|
|
uint16_t rgb[2]; // 565 colors
|
|
uint32_t bitmap; // 2bpp rgb bitmap
|
|
};
|
|
|
|
// BC2/DXT2/3 compression (8 bits per texel)
|
|
struct D3DX_BC2
|
|
{
|
|
uint32_t bitmap[2]; // 4bpp alpha bitmap
|
|
D3DX_BC1 bc1; // BC1 rgb data
|
|
};
|
|
|
|
// BC3/DXT4/5 compression (8 bits per texel)
|
|
struct D3DX_BC3
|
|
{
|
|
uint8_t alpha[2]; // alpha values
|
|
uint8_t bitmap[6]; // 3bpp alpha bitmap
|
|
D3DX_BC1 bc1; // BC1 rgb data
|
|
};
|
|
#pragma pack(pop)
|
|
|
|
//-------------------------------------------------------------------------------------
|
|
// Templates
|
|
//-------------------------------------------------------------------------------------
|
|
#pragma warning(push)
|
|
#pragma warning(disable : 4127)
|
|
template <bool bRange> void OptimizeAlpha(float *pX, float *pY, const float *pPoints, size_t cSteps)
|
|
{
|
|
static const float pC6[] = { 5.0f / 5.0f, 4.0f / 5.0f, 3.0f / 5.0f, 2.0f / 5.0f, 1.0f / 5.0f, 0.0f / 5.0f };
|
|
static const float pD6[] = { 0.0f / 5.0f, 1.0f / 5.0f, 2.0f / 5.0f, 3.0f / 5.0f, 4.0f / 5.0f, 5.0f / 5.0f };
|
|
static const float pC8[] = { 7.0f / 7.0f, 6.0f / 7.0f, 5.0f / 7.0f, 4.0f / 7.0f, 3.0f / 7.0f, 2.0f / 7.0f, 1.0f / 7.0f, 0.0f / 7.0f };
|
|
static const float pD8[] = { 0.0f / 7.0f, 1.0f / 7.0f, 2.0f / 7.0f, 3.0f / 7.0f, 4.0f / 7.0f, 5.0f / 7.0f, 6.0f / 7.0f, 7.0f / 7.0f };
|
|
|
|
const float *pC = (6 == cSteps) ? pC6 : pC8;
|
|
const float *pD = (6 == cSteps) ? pD6 : pD8;
|
|
|
|
float MAX_VALUE = 1.0f;
|
|
float MIN_VALUE;
|
|
if (bRange)
|
|
{
|
|
MIN_VALUE = -1.0f;
|
|
}
|
|
else
|
|
{
|
|
MIN_VALUE = 0.0f;
|
|
}
|
|
|
|
// Find Min and Max points, as starting point
|
|
float fX = MAX_VALUE;
|
|
float fY = MIN_VALUE;
|
|
|
|
if (8 == cSteps)
|
|
{
|
|
for (size_t iPoint = 0; iPoint < NUM_PIXELS_PER_BLOCK; iPoint++)
|
|
{
|
|
if (pPoints[iPoint] < fX)
|
|
fX = pPoints[iPoint];
|
|
|
|
if (pPoints[iPoint] > fY)
|
|
fY = pPoints[iPoint];
|
|
}
|
|
}
|
|
else
|
|
{
|
|
for (size_t iPoint = 0; iPoint < NUM_PIXELS_PER_BLOCK; iPoint++)
|
|
{
|
|
if (pPoints[iPoint] < fX && pPoints[iPoint] > MIN_VALUE)
|
|
fX = pPoints[iPoint];
|
|
|
|
if (pPoints[iPoint] > fY && pPoints[iPoint] < MAX_VALUE)
|
|
fY = pPoints[iPoint];
|
|
}
|
|
|
|
if (fX == fY)
|
|
{
|
|
fY = MAX_VALUE;
|
|
}
|
|
}
|
|
|
|
// Use Newton's Method to find local minima of sum-of-squares error.
|
|
float fSteps = (float)(cSteps - 1);
|
|
|
|
for (size_t iIteration = 0; iIteration < 8; iIteration++)
|
|
{
|
|
float fScale;
|
|
|
|
if ((fY - fX) < (1.0f / 256.0f))
|
|
break;
|
|
|
|
fScale = fSteps / (fY - fX);
|
|
|
|
// Calculate new steps
|
|
float pSteps[8];
|
|
|
|
for (size_t iStep = 0; iStep < cSteps; iStep++)
|
|
pSteps[iStep] = pC[iStep] * fX + pD[iStep] * fY;
|
|
|
|
if (6 == cSteps)
|
|
{
|
|
pSteps[6] = MIN_VALUE;
|
|
pSteps[7] = MAX_VALUE;
|
|
}
|
|
|
|
// Evaluate function, and derivatives
|
|
float dX = 0.0f;
|
|
float dY = 0.0f;
|
|
float d2X = 0.0f;
|
|
float d2Y = 0.0f;
|
|
|
|
for (size_t iPoint = 0; iPoint < NUM_PIXELS_PER_BLOCK; iPoint++)
|
|
{
|
|
float fDot = (pPoints[iPoint] - fX) * fScale;
|
|
|
|
size_t iStep;
|
|
|
|
if (fDot <= 0.0f)
|
|
iStep = ((6 == cSteps) && (pPoints[iPoint] <= fX * 0.5f)) ? 6 : 0;
|
|
else if (fDot >= fSteps)
|
|
iStep = ((6 == cSteps) && (pPoints[iPoint] >= (fY + 1.0f) * 0.5f)) ? 7 : (cSteps - 1);
|
|
else
|
|
iStep = static_cast<int32_t>(fDot + 0.5f);
|
|
|
|
|
|
if (iStep < cSteps)
|
|
{
|
|
// D3DX had this computation backwards (pPoints[iPoint] - pSteps[iStep])
|
|
// this fix improves RMS of the alpha component
|
|
float fDiff = pSteps[iStep] - pPoints[iPoint];
|
|
|
|
dX += pC[iStep] * fDiff;
|
|
d2X += pC[iStep] * pC[iStep];
|
|
|
|
dY += pD[iStep] * fDiff;
|
|
d2Y += pD[iStep] * pD[iStep];
|
|
}
|
|
}
|
|
|
|
// Move endpoints
|
|
if (d2X > 0.0f)
|
|
fX -= dX / d2X;
|
|
|
|
if (d2Y > 0.0f)
|
|
fY -= dY / d2Y;
|
|
|
|
if (fX > fY)
|
|
{
|
|
float f = fX; fX = fY; fY = f;
|
|
}
|
|
|
|
if ((dX * dX < (1.0f / 64.0f)) && (dY * dY < (1.0f / 64.0f)))
|
|
break;
|
|
}
|
|
|
|
*pX = (fX < MIN_VALUE) ? MIN_VALUE : (fX > MAX_VALUE) ? MAX_VALUE : fX;
|
|
*pY = (fY < MIN_VALUE) ? MIN_VALUE : (fY > MAX_VALUE) ? MAX_VALUE : fY;
|
|
}
|
|
#pragma warning(pop)
|
|
|
|
//-------------------------------------------------------------------------------------
|
|
// Functions
|
|
//-------------------------------------------------------------------------------------
|
|
|
|
typedef void (*BC_DECODE)(XMVECTOR *pColor, const uint8_t *pBC);
|
|
typedef void (*BC_ENCODE)(uint8_t *pDXT, const XMVECTOR *pColor, DWORD flags);
|
|
|
|
void D3DXDecodeBC1(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(8) const uint8_t *pBC);
|
|
void D3DXDecodeBC2(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(16) const uint8_t *pBC);
|
|
void D3DXDecodeBC3(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(16) const uint8_t *pBC);
|
|
void D3DXDecodeBC4U(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(8) const uint8_t *pBC);
|
|
void D3DXDecodeBC4S(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(8) const uint8_t *pBC);
|
|
void D3DXDecodeBC5U(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(16) const uint8_t *pBC);
|
|
void D3DXDecodeBC5S(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(16) const uint8_t *pBC);
|
|
void D3DXDecodeBC6HU(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(16) const uint8_t *pBC);
|
|
void D3DXDecodeBC6HS(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(16) const uint8_t *pBC);
|
|
void D3DXDecodeBC7(_Out_writes_(NUM_PIXELS_PER_BLOCK) XMVECTOR *pColor, _In_reads_(16) const uint8_t *pBC);
|
|
|
|
void D3DXEncodeBC1(_Out_writes_(8) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ float threshold, _In_ DWORD flags);
|
|
// BC1 requires one additional parameter, so it doesn't match signature of BC_ENCODE above
|
|
|
|
void D3DXEncodeBC2(_Out_writes_(16) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ DWORD flags);
|
|
void D3DXEncodeBC3(_Out_writes_(16) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ DWORD flags);
|
|
void D3DXEncodeBC4U(_Out_writes_(8) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ DWORD flags);
|
|
void D3DXEncodeBC4S(_Out_writes_(8) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ DWORD flags);
|
|
void D3DXEncodeBC5U(_Out_writes_(16) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ DWORD flags);
|
|
void D3DXEncodeBC5S(_Out_writes_(16) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ DWORD flags);
|
|
void D3DXEncodeBC6HU(_Out_writes_(16) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ DWORD flags);
|
|
void D3DXEncodeBC6HS(_Out_writes_(16) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ DWORD flags);
|
|
void D3DXEncodeBC7(_Out_writes_(16) uint8_t *pBC, _In_reads_(NUM_PIXELS_PER_BLOCK) const XMVECTOR *pColor, _In_ DWORD flags);
|
|
|
|
}; // namespace
|