mirror of
https://github.com/godotengine/godot.git
synced 2024-12-15 10:12:40 +08:00
475 lines
16 KiB
C++
475 lines
16 KiB
C++
/*
|
|
* Copyright 2015 The Etc2Comp Authors.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
/*
|
|
EtcBlock4x4Encoding_RGBA8.cpp contains:
|
|
Block4x4Encoding_RGBA8
|
|
Block4x4Encoding_RGBA8_Opaque
|
|
Block4x4Encoding_RGBA8_Transparent
|
|
|
|
These encoders are used when targetting file format RGBA8.
|
|
|
|
Block4x4Encoding_RGBA8_Opaque is used when all pixels in the 4x4 block are opaque
|
|
Block4x4Encoding_RGBA8_Transparent is used when all pixels in the 4x4 block are transparent
|
|
Block4x4Encoding_RGBA8 is used when there is a mixture of alphas in the 4x4 block
|
|
|
|
*/
|
|
|
|
#include "EtcConfig.h"
|
|
#include "EtcBlock4x4Encoding_RGBA8.h"
|
|
|
|
#include "EtcBlock4x4EncodingBits.h"
|
|
#include "EtcBlock4x4.h"
|
|
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <assert.h>
|
|
#include <float.h>
|
|
#include <limits>
|
|
|
|
namespace Etc
|
|
{
|
|
|
|
// ####################################################################################################
|
|
// Block4x4Encoding_RGBA8
|
|
// ####################################################################################################
|
|
|
|
float Block4x4Encoding_RGBA8::s_aafModifierTable[MODIFIER_TABLE_ENTRYS][ALPHA_SELECTORS]
|
|
{
|
|
{ -3.0f / 255.0f, -6.0f / 255.0f, -9.0f / 255.0f, -15.0f / 255.0f, 2.0f / 255.0f, 5.0f / 255.0f, 8.0f / 255.0f, 14.0f / 255.0f },
|
|
{ -3.0f / 255.0f, -7.0f / 255.0f, -10.0f / 255.0f, -13.0f / 255.0f, 2.0f / 255.0f, 6.0f / 255.0f, 9.0f / 255.0f, 12.0f / 255.0f },
|
|
{ -2.0f / 255.0f, -5.0f / 255.0f, -8.0f / 255.0f, -13.0f / 255.0f, 1.0f / 255.0f, 4.0f / 255.0f, 7.0f / 255.0f, 12.0f / 255.0f },
|
|
{ -2.0f / 255.0f, -4.0f / 255.0f, -6.0f / 255.0f, -13.0f / 255.0f, 1.0f / 255.0f, 3.0f / 255.0f, 5.0f / 255.0f, 12.0f / 255.0f },
|
|
|
|
{ -3.0f / 255.0f, -6.0f / 255.0f, -8.0f / 255.0f, -12.0f / 255.0f, 2.0f / 255.0f, 5.0f / 255.0f, 7.0f / 255.0f, 11.0f / 255.0f },
|
|
{ -3.0f / 255.0f, -7.0f / 255.0f, -9.0f / 255.0f, -11.0f / 255.0f, 2.0f / 255.0f, 6.0f / 255.0f, 8.0f / 255.0f, 10.0f / 255.0f },
|
|
{ -4.0f / 255.0f, -7.0f / 255.0f, -8.0f / 255.0f, -11.0f / 255.0f, 3.0f / 255.0f, 6.0f / 255.0f, 7.0f / 255.0f, 10.0f / 255.0f },
|
|
{ -3.0f / 255.0f, -5.0f / 255.0f, -8.0f / 255.0f, -11.0f / 255.0f, 2.0f / 255.0f, 4.0f / 255.0f, 7.0f / 255.0f, 10.0f / 255.0f },
|
|
|
|
{ -2.0f / 255.0f, -6.0f / 255.0f, -8.0f / 255.0f, -10.0f / 255.0f, 1.0f / 255.0f, 5.0f / 255.0f, 7.0f / 255.0f, 9.0f / 255.0f },
|
|
{ -2.0f / 255.0f, -5.0f / 255.0f, -8.0f / 255.0f, -10.0f / 255.0f, 1.0f / 255.0f, 4.0f / 255.0f, 7.0f / 255.0f, 9.0f / 255.0f },
|
|
{ -2.0f / 255.0f, -4.0f / 255.0f, -8.0f / 255.0f, -10.0f / 255.0f, 1.0f / 255.0f, 3.0f / 255.0f, 7.0f / 255.0f, 9.0f / 255.0f },
|
|
{ -2.0f / 255.0f, -5.0f / 255.0f, -7.0f / 255.0f, -10.0f / 255.0f, 1.0f / 255.0f, 4.0f / 255.0f, 6.0f / 255.0f, 9.0f / 255.0f },
|
|
|
|
{ -3.0f / 255.0f, -4.0f / 255.0f, -7.0f / 255.0f, -10.0f / 255.0f, 2.0f / 255.0f, 3.0f / 255.0f, 6.0f / 255.0f, 9.0f / 255.0f },
|
|
{ -1.0f / 255.0f, -2.0f / 255.0f, -3.0f / 255.0f, -10.0f / 255.0f, 0.0f / 255.0f, 1.0f / 255.0f, 2.0f / 255.0f, 9.0f / 255.0f },
|
|
{ -4.0f / 255.0f, -6.0f / 255.0f, -8.0f / 255.0f, -9.0f / 255.0f, 3.0f / 255.0f, 5.0f / 255.0f, 7.0f / 255.0f, 8.0f / 255.0f },
|
|
{ -3.0f / 255.0f, -5.0f / 255.0f, -7.0f / 255.0f, -9.0f / 255.0f, 2.0f / 255.0f, 4.0f / 255.0f, 6.0f / 255.0f, 8.0f / 255.0f }
|
|
};
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
//
|
|
Block4x4Encoding_RGBA8::Block4x4Encoding_RGBA8(void)
|
|
{
|
|
|
|
m_pencodingbitsA8 = nullptr;
|
|
|
|
}
|
|
Block4x4Encoding_RGBA8::~Block4x4Encoding_RGBA8(void) {}
|
|
// ----------------------------------------------------------------------------------------------------
|
|
// initialization prior to encoding
|
|
// a_pblockParent points to the block associated with this encoding
|
|
// a_errormetric is used to choose the best encoding
|
|
// a_pafrgbaSource points to a 4x4 block subset of the source image
|
|
// a_paucEncodingBits points to the final encoding bits
|
|
//
|
|
void Block4x4Encoding_RGBA8::InitFromSource(Block4x4 *a_pblockParent,
|
|
ColorFloatRGBA *a_pafrgbaSource,
|
|
unsigned char *a_paucEncodingBits, ErrorMetric a_errormetric)
|
|
{
|
|
Block4x4Encoding::Init(a_pblockParent, a_pafrgbaSource,a_errormetric);
|
|
|
|
m_pencodingbitsA8 = (Block4x4EncodingBits_A8 *)a_paucEncodingBits;
|
|
m_pencodingbitsRGB8 = (Block4x4EncodingBits_RGB8 *)(a_paucEncodingBits + sizeof(Block4x4EncodingBits_A8));
|
|
|
|
}
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
// initialization from the encoding bits of a previous encoding
|
|
// a_pblockParent points to the block associated with this encoding
|
|
// a_errormetric is used to choose the best encoding
|
|
// a_pafrgbaSource points to a 4x4 block subset of the source image
|
|
// a_paucEncodingBits points to the final encoding bits of a previous encoding
|
|
//
|
|
void Block4x4Encoding_RGBA8::InitFromEncodingBits(Block4x4 *a_pblockParent,
|
|
unsigned char *a_paucEncodingBits,
|
|
ColorFloatRGBA *a_pafrgbaSource,
|
|
ErrorMetric a_errormetric)
|
|
{
|
|
|
|
m_pencodingbitsA8 = (Block4x4EncodingBits_A8 *)a_paucEncodingBits;
|
|
m_pencodingbitsRGB8 = (Block4x4EncodingBits_RGB8 *)(a_paucEncodingBits + sizeof(Block4x4EncodingBits_A8));
|
|
|
|
// init RGB portion
|
|
Block4x4Encoding_RGB8::InitFromEncodingBits(a_pblockParent,
|
|
(unsigned char *) m_pencodingbitsRGB8,
|
|
a_pafrgbaSource,
|
|
a_errormetric);
|
|
|
|
// init A8 portion
|
|
// has to be done after InitFromEncodingBits()
|
|
{
|
|
m_fBase = m_pencodingbitsA8->data.base / 255.0f;
|
|
m_fMultiplier = (float)m_pencodingbitsA8->data.multiplier;
|
|
m_uiModifierTableIndex = m_pencodingbitsA8->data.table;
|
|
|
|
unsigned long long int ulliSelectorBits = 0;
|
|
ulliSelectorBits |= (unsigned long long int)m_pencodingbitsA8->data.selectors0 << 40;
|
|
ulliSelectorBits |= (unsigned long long int)m_pencodingbitsA8->data.selectors1 << 32;
|
|
ulliSelectorBits |= (unsigned long long int)m_pencodingbitsA8->data.selectors2 << 24;
|
|
ulliSelectorBits |= (unsigned long long int)m_pencodingbitsA8->data.selectors3 << 16;
|
|
ulliSelectorBits |= (unsigned long long int)m_pencodingbitsA8->data.selectors4 << 8;
|
|
ulliSelectorBits |= (unsigned long long int)m_pencodingbitsA8->data.selectors5;
|
|
for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++)
|
|
{
|
|
unsigned int uiShift = 45 - (3 * uiPixel);
|
|
m_auiAlphaSelectors[uiPixel] = (ulliSelectorBits >> uiShift) & (ALPHA_SELECTORS - 1);
|
|
}
|
|
|
|
// decode the alphas
|
|
// calc alpha error
|
|
m_fError = 0.0f;
|
|
for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++)
|
|
{
|
|
m_afDecodedAlphas[uiPixel] = DecodePixelAlpha(m_fBase, m_fMultiplier,
|
|
m_uiModifierTableIndex,
|
|
m_auiAlphaSelectors[uiPixel]);
|
|
|
|
float fDeltaAlpha = m_afDecodedAlphas[uiPixel] - m_pafrgbaSource[uiPixel].fA;
|
|
m_fError += fDeltaAlpha * fDeltaAlpha;
|
|
}
|
|
}
|
|
|
|
// redo error calc to include alpha
|
|
CalcBlockError();
|
|
|
|
}
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
// perform a single encoding iteration
|
|
// replace the encoding if a better encoding was found
|
|
// subsequent iterations generally take longer for each iteration
|
|
// set m_boolDone if encoding is perfect or encoding is finished based on a_fEffort
|
|
//
|
|
// similar to Block4x4Encoding_RGB8_Base::Encode_RGB8(), but with alpha added
|
|
//
|
|
void Block4x4Encoding_RGBA8::PerformIteration(float a_fEffort)
|
|
{
|
|
assert(!m_boolDone);
|
|
|
|
if (m_uiEncodingIterations == 0)
|
|
{
|
|
if (a_fEffort < 24.9f)
|
|
{
|
|
CalculateA8(0.0f);
|
|
}
|
|
else if (a_fEffort < 49.9f)
|
|
{
|
|
CalculateA8(1.0f);
|
|
}
|
|
else
|
|
{
|
|
CalculateA8(2.0f);
|
|
}
|
|
}
|
|
|
|
Block4x4Encoding_RGB8::PerformIteration(a_fEffort);
|
|
|
|
}
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
// find the best combination of base alpga, multiplier and selectors
|
|
//
|
|
// a_fRadius limits the range of base alpha to try
|
|
//
|
|
void Block4x4Encoding_RGBA8::CalculateA8(float a_fRadius)
|
|
{
|
|
|
|
// find min/max alpha
|
|
float fMinAlpha = 1.0f;
|
|
float fMaxAlpha = 0.0f;
|
|
for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++)
|
|
{
|
|
float fAlpha = m_pafrgbaSource[uiPixel].fA;
|
|
|
|
// ignore border pixels
|
|
if (isnan(fAlpha))
|
|
{
|
|
continue;
|
|
}
|
|
|
|
if (fAlpha < fMinAlpha)
|
|
{
|
|
fMinAlpha = fAlpha;
|
|
}
|
|
if (fAlpha > fMaxAlpha)
|
|
{
|
|
fMaxAlpha = fAlpha;
|
|
}
|
|
}
|
|
assert(fMinAlpha <= fMaxAlpha);
|
|
|
|
float fAlphaRange = fMaxAlpha - fMinAlpha;
|
|
|
|
// try each modifier table entry
|
|
m_fError = FLT_MAX; // artificially high value
|
|
for (unsigned int uiTableEntry = 0; uiTableEntry < MODIFIER_TABLE_ENTRYS; uiTableEntry++)
|
|
{
|
|
static const unsigned int MIN_VALUE_SELECTOR = 3;
|
|
static const unsigned int MAX_VALUE_SELECTOR = 7;
|
|
|
|
float fTableEntryCenter = -s_aafModifierTable[uiTableEntry][MIN_VALUE_SELECTOR];
|
|
|
|
float fTableEntryRange = s_aafModifierTable[uiTableEntry][MAX_VALUE_SELECTOR] -
|
|
s_aafModifierTable[uiTableEntry][MIN_VALUE_SELECTOR];
|
|
|
|
float fCenterRatio = fTableEntryCenter / fTableEntryRange;
|
|
|
|
float fCenter = fMinAlpha + fCenterRatio*fAlphaRange;
|
|
fCenter = roundf(255.0f * fCenter) / 255.0f;
|
|
|
|
float fMinBase = fCenter - (a_fRadius / 255.0f);
|
|
if (fMinBase < 0.0f)
|
|
{
|
|
fMinBase = 0.0f;
|
|
}
|
|
|
|
float fMaxBase = fCenter + (a_fRadius / 255.0f);
|
|
if (fMaxBase > 1.0f)
|
|
{
|
|
fMaxBase = 1.0f;
|
|
}
|
|
|
|
for (float fBase = fMinBase; fBase <= fMaxBase; fBase += (0.999999f / 255.0f))
|
|
{
|
|
|
|
float fRangeMultiplier = roundf(fAlphaRange / fTableEntryRange);
|
|
|
|
float fMinMultiplier = fRangeMultiplier - a_fRadius;
|
|
if (fMinMultiplier < 1.0f)
|
|
{
|
|
fMinMultiplier = 1.0f;
|
|
}
|
|
else if (fMinMultiplier > 15.0f)
|
|
{
|
|
fMinMultiplier = 15.0f;
|
|
}
|
|
|
|
float fMaxMultiplier = fRangeMultiplier + a_fRadius;
|
|
if (fMaxMultiplier < 1.0f)
|
|
{
|
|
fMaxMultiplier = 1.0f;
|
|
}
|
|
else if (fMaxMultiplier > 15.0f)
|
|
{
|
|
fMaxMultiplier = 15.0f;
|
|
}
|
|
|
|
for (float fMultiplier = fMinMultiplier; fMultiplier <= fMaxMultiplier; fMultiplier += 1.0f)
|
|
{
|
|
// find best selector for each pixel
|
|
unsigned int auiBestSelectors[PIXELS];
|
|
float afBestAlphaError[PIXELS];
|
|
float afBestDecodedAlphas[PIXELS];
|
|
for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++)
|
|
{
|
|
float fBestPixelAlphaError = FLT_MAX;
|
|
for (unsigned int uiSelector = 0; uiSelector < ALPHA_SELECTORS; uiSelector++)
|
|
{
|
|
float fDecodedAlpha = DecodePixelAlpha(fBase, fMultiplier, uiTableEntry, uiSelector);
|
|
|
|
// border pixels (NAN) should have zero error
|
|
float fPixelDeltaAlpha = isnan(m_pafrgbaSource[uiPixel].fA) ?
|
|
0.0f :
|
|
fDecodedAlpha - m_pafrgbaSource[uiPixel].fA;
|
|
|
|
float fPixelAlphaError = fPixelDeltaAlpha * fPixelDeltaAlpha;
|
|
|
|
if (fPixelAlphaError < fBestPixelAlphaError)
|
|
{
|
|
fBestPixelAlphaError = fPixelAlphaError;
|
|
auiBestSelectors[uiPixel] = uiSelector;
|
|
afBestAlphaError[uiPixel] = fBestPixelAlphaError;
|
|
afBestDecodedAlphas[uiPixel] = fDecodedAlpha;
|
|
}
|
|
}
|
|
}
|
|
|
|
float fBlockError = 0.0f;
|
|
for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++)
|
|
{
|
|
fBlockError += afBestAlphaError[uiPixel];
|
|
}
|
|
|
|
if (fBlockError < m_fError)
|
|
{
|
|
m_fError = fBlockError;
|
|
|
|
m_fBase = fBase;
|
|
m_fMultiplier = fMultiplier;
|
|
m_uiModifierTableIndex = uiTableEntry;
|
|
for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++)
|
|
{
|
|
m_auiAlphaSelectors[uiPixel] = auiBestSelectors[uiPixel];
|
|
m_afDecodedAlphas[uiPixel] = afBestDecodedAlphas[uiPixel];
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
// set the encoding bits based on encoding state
|
|
//
|
|
void Block4x4Encoding_RGBA8::SetEncodingBits(void)
|
|
{
|
|
|
|
// set the RGB8 portion
|
|
Block4x4Encoding_RGB8::SetEncodingBits();
|
|
|
|
// set the A8 portion
|
|
{
|
|
m_pencodingbitsA8->data.base = (unsigned char)roundf(255.0f * m_fBase);
|
|
m_pencodingbitsA8->data.table = m_uiModifierTableIndex;
|
|
m_pencodingbitsA8->data.multiplier = (unsigned char)roundf(m_fMultiplier);
|
|
|
|
unsigned long long int ulliSelectorBits = 0;
|
|
for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++)
|
|
{
|
|
unsigned int uiShift = 45 - (3 * uiPixel);
|
|
ulliSelectorBits |= ((unsigned long long int)m_auiAlphaSelectors[uiPixel]) << uiShift;
|
|
}
|
|
|
|
m_pencodingbitsA8->data.selectors0 = ulliSelectorBits >> 40;
|
|
m_pencodingbitsA8->data.selectors1 = ulliSelectorBits >> 32;
|
|
m_pencodingbitsA8->data.selectors2 = ulliSelectorBits >> 24;
|
|
m_pencodingbitsA8->data.selectors3 = ulliSelectorBits >> 16;
|
|
m_pencodingbitsA8->data.selectors4 = ulliSelectorBits >> 8;
|
|
m_pencodingbitsA8->data.selectors5 = ulliSelectorBits;
|
|
}
|
|
|
|
}
|
|
|
|
// ####################################################################################################
|
|
// Block4x4Encoding_RGBA8_Opaque
|
|
// ####################################################################################################
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
// perform a single encoding iteration
|
|
// replace the encoding if a better encoding was found
|
|
// subsequent iterations generally take longer for each iteration
|
|
// set m_boolDone if encoding is perfect or encoding is finished based on a_fEffort
|
|
//
|
|
void Block4x4Encoding_RGBA8_Opaque::PerformIteration(float a_fEffort)
|
|
{
|
|
assert(!m_boolDone);
|
|
|
|
if (m_uiEncodingIterations == 0)
|
|
{
|
|
m_fError = 0.0f;
|
|
|
|
for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++)
|
|
{
|
|
m_afDecodedAlphas[uiPixel] = 1.0f;
|
|
}
|
|
}
|
|
|
|
Block4x4Encoding_RGB8::PerformIteration(a_fEffort);
|
|
|
|
}
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
// set the encoding bits based on encoding state
|
|
//
|
|
void Block4x4Encoding_RGBA8_Opaque::SetEncodingBits(void)
|
|
{
|
|
|
|
// set the RGB8 portion
|
|
Block4x4Encoding_RGB8::SetEncodingBits();
|
|
|
|
// set the A8 portion
|
|
m_pencodingbitsA8->data.base = 255;
|
|
m_pencodingbitsA8->data.table = 15;
|
|
m_pencodingbitsA8->data.multiplier = 15;
|
|
m_pencodingbitsA8->data.selectors0 = 0xFF;
|
|
m_pencodingbitsA8->data.selectors1 = 0xFF;
|
|
m_pencodingbitsA8->data.selectors2 = 0xFF;
|
|
m_pencodingbitsA8->data.selectors3 = 0xFF;
|
|
m_pencodingbitsA8->data.selectors4 = 0xFF;
|
|
m_pencodingbitsA8->data.selectors5 = 0xFF;
|
|
|
|
}
|
|
|
|
// ####################################################################################################
|
|
// Block4x4Encoding_RGBA8_Transparent
|
|
// ####################################################################################################
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
// perform a single encoding iteration
|
|
// replace the encoding if a better encoding was found
|
|
// subsequent iterations generally take longer for each iteration
|
|
// set m_boolDone if encoding is perfect or encoding is finished based on a_fEffort
|
|
//
|
|
void Block4x4Encoding_RGBA8_Transparent::PerformIteration(float )
|
|
{
|
|
assert(!m_boolDone);
|
|
assert(m_uiEncodingIterations == 0);
|
|
|
|
m_mode = MODE_ETC1;
|
|
m_boolDiff = true;
|
|
m_boolFlip = false;
|
|
|
|
for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++)
|
|
{
|
|
m_afrgbaDecodedColors[uiPixel] = ColorFloatRGBA();
|
|
m_afDecodedAlphas[uiPixel] = 0.0f;
|
|
}
|
|
|
|
m_fError = 0.0f;
|
|
|
|
m_boolDone = true;
|
|
m_uiEncodingIterations++;
|
|
|
|
}
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
// set the encoding bits based on encoding state
|
|
//
|
|
void Block4x4Encoding_RGBA8_Transparent::SetEncodingBits(void)
|
|
{
|
|
|
|
Block4x4Encoding_RGB8::SetEncodingBits();
|
|
|
|
// set the A8 portion
|
|
m_pencodingbitsA8->data.base = 0;
|
|
m_pencodingbitsA8->data.table = 0;
|
|
m_pencodingbitsA8->data.multiplier = 1;
|
|
m_pencodingbitsA8->data.selectors0 = 0;
|
|
m_pencodingbitsA8->data.selectors1 = 0;
|
|
m_pencodingbitsA8->data.selectors2 = 0;
|
|
m_pencodingbitsA8->data.selectors3 = 0;
|
|
m_pencodingbitsA8->data.selectors4 = 0;
|
|
m_pencodingbitsA8->data.selectors5 = 0;
|
|
|
|
}
|
|
|
|
// ----------------------------------------------------------------------------------------------------
|
|
//
|
|
}
|