pandemonium_engine_minimal/thirdparty/etc2comp/EtcBlock4x4.cpp
2023-12-14 21:54:22 +01:00

426 lines
11 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.
*/
/*
EtcBlock4x4.cpp
Implements the state associated with each 4x4 block of pixels in an image
Source images that are not a multiple of 4x4 are extended to fill the Block4x4 using pixels with an
alpha of NAN
*/
#include "EtcConfig.h"
#include "EtcBlock4x4.h"
#include "EtcBlock4x4EncodingBits.h"
#include "EtcColor.h"
#include "EtcImage.h"
#include "EtcColorFloatRGBA.h"
#include "EtcBlock4x4Encoding_RGB8.h"
#include "EtcBlock4x4Encoding_RGBA8.h"
#include "EtcBlock4x4Encoding_RGB8A1.h"
#include "EtcBlock4x4Encoding_R11.h"
#include "EtcBlock4x4Encoding_RG11.h"
#include <stdio.h>
#include <string.h>
#include <assert.h>
namespace Etc
{
// ETC pixels are scanned vertically.
// this mapping is for when someone wants to scan the ETC pixels horizontally
const unsigned int Block4x4::s_auiPixelOrderHScan[PIXELS] = { 0, 4, 8, 12, 1, 5, 9, 13, 2, 6, 10, 14, 3, 7, 11, 15 };
// ----------------------------------------------------------------------------------------------------
//
Block4x4::Block4x4(void)
{
m_pimageSource = nullptr;
m_uiSourceH = 0;
m_uiSourceV = 0;
m_sourcealphamix = SourceAlphaMix::UNKNOWN;
m_boolBorderPixels = false;
m_boolPunchThroughPixels = false;
m_pencoding = nullptr;
m_errormetric = ErrorMetric::NUMERIC;
}
Block4x4::~Block4x4()
{
m_pimageSource = nullptr;
if (m_pencoding)
{
delete m_pencoding;
m_pencoding = nullptr;
}
}
// ----------------------------------------------------------------------------------------------------
// initialization prior to encoding from a source image
// [a_uiSourceH,a_uiSourceV] is the location of the block in a_pimageSource
// a_paucEncodingBits is the place to store the final encoding
// a_errormetric is used for finding the best encoding
//
void Block4x4::InitFromSource(Image *a_pimageSource,
unsigned int a_uiSourceH, unsigned int a_uiSourceV,
unsigned char *a_paucEncodingBits,
ErrorMetric a_errormetric)
{
Block4x4();
m_pimageSource = a_pimageSource;
m_uiSourceH = a_uiSourceH;
m_uiSourceV = a_uiSourceV;
m_errormetric = a_errormetric;
SetSourcePixels();
// set block encoder function
switch (m_pimageSource->GetFormat())
{
case Image::Format::ETC1:
m_pencoding = new Block4x4Encoding_ETC1;
break;
case Image::Format::RGB8:
case Image::Format::SRGB8:
m_pencoding = new Block4x4Encoding_RGB8;
break;
case Image::Format::RGBA8:
case Image::Format::SRGBA8:
if (a_errormetric == RGBX)
{
m_pencoding = new Block4x4Encoding_RGBA8;
}
else
{
switch (m_sourcealphamix)
{
case SourceAlphaMix::OPAQUE:
m_pencoding = new Block4x4Encoding_RGBA8_Opaque;
break;
case SourceAlphaMix::TRANSPARENT:
m_pencoding = new Block4x4Encoding_RGBA8_Transparent;
break;
case SourceAlphaMix::TRANSLUCENT:
m_pencoding = new Block4x4Encoding_RGBA8;
break;
default:
assert(0);
break;
}
break;
}
break;
case Image::Format::RGB8A1:
case Image::Format::SRGB8A1:
switch (m_sourcealphamix)
{
case SourceAlphaMix::OPAQUE:
m_pencoding = new Block4x4Encoding_RGB8A1_Opaque;
break;
case SourceAlphaMix::TRANSPARENT:
m_pencoding = new Block4x4Encoding_RGB8A1_Transparent;
break;
case SourceAlphaMix::TRANSLUCENT:
if (m_boolPunchThroughPixels)
{
m_pencoding = new Block4x4Encoding_RGB8A1;
}
else
{
m_pencoding = new Block4x4Encoding_RGB8A1_Opaque;
}
break;
default:
assert(0);
break;
}
break;
case Image::Format::R11:
case Image::Format::SIGNED_R11:
m_pencoding = new Block4x4Encoding_R11;
break;
case Image::Format::RG11:
case Image::Format::SIGNED_RG11:
m_pencoding = new Block4x4Encoding_RG11;
break;
default:
assert(0);
break;
}
m_pencoding->InitFromSource(this, m_afrgbaSource,
a_paucEncodingBits, a_errormetric);
}
// ----------------------------------------------------------------------------------------------------
// initialization of encoding state from a prior encoding using encoding bits
// [a_uiSourceH,a_uiSourceV] is the location of the block in a_pimageSource
// a_paucEncodingBits is the place to read the prior encoding
// a_imageformat is used to determine how to interpret a_paucEncodingBits
// a_errormetric was used for the prior encoding
//
void Block4x4::InitFromEtcEncodingBits(Image::Format a_imageformat,
unsigned int a_uiSourceH, unsigned int a_uiSourceV,
unsigned char *a_paucEncodingBits,
Image *a_pimageSource,
ErrorMetric a_errormetric)
{
Block4x4();
m_pimageSource = a_pimageSource;
m_uiSourceH = a_uiSourceH;
m_uiSourceV = a_uiSourceV;
m_errormetric = a_errormetric;
SetSourcePixels();
// set block encoder function
switch (a_imageformat)
{
case Image::Format::ETC1:
m_pencoding = new Block4x4Encoding_ETC1;
break;
case Image::Format::RGB8:
case Image::Format::SRGB8:
m_pencoding = new Block4x4Encoding_RGB8;
break;
case Image::Format::RGBA8:
case Image::Format::SRGBA8:
m_pencoding = new Block4x4Encoding_RGBA8;
break;
case Image::Format::RGB8A1:
case Image::Format::SRGB8A1:
m_pencoding = new Block4x4Encoding_RGB8A1;
break;
case Image::Format::R11:
case Image::Format::SIGNED_R11:
m_pencoding = new Block4x4Encoding_R11;
break;
case Image::Format::RG11:
case Image::Format::SIGNED_RG11:
m_pencoding = new Block4x4Encoding_RG11;
break;
default:
assert(0);
break;
}
m_pencoding->InitFromEncodingBits(this, a_paucEncodingBits, m_afrgbaSource,
m_pimageSource->GetErrorMetric());
}
// ----------------------------------------------------------------------------------------------------
// set source pixels from m_pimageSource
// set m_alphamix
//
void Block4x4::SetSourcePixels(void)
{
Image::Format imageformat = m_pimageSource->GetFormat();
// alpha census
unsigned int uiTransparentSourcePixels = 0;
unsigned int uiOpaqueSourcePixels = 0;
// copy source to consecutive memory locations
// convert from image horizontal scan to block vertical scan
unsigned int uiPixel = 0;
for (unsigned int uiBlockPixelH = 0; uiBlockPixelH < Block4x4::COLUMNS; uiBlockPixelH++)
{
unsigned int uiSourcePixelH = m_uiSourceH + uiBlockPixelH;
for (unsigned int uiBlockPixelV = 0; uiBlockPixelV < Block4x4::ROWS; uiBlockPixelV++)
{
unsigned int uiSourcePixelV = m_uiSourceV + uiBlockPixelV;
ColorFloatRGBA *pfrgbaSource = m_pimageSource->GetSourcePixel(uiSourcePixelH, uiSourcePixelV);
// if pixel extends beyond source image because of block padding
if (pfrgbaSource == nullptr)
{
m_afrgbaSource[uiPixel] = ColorFloatRGBA(0.0f, 0.0f, 0.0f, NAN); // denotes border pixel
m_boolBorderPixels = true;
uiTransparentSourcePixels++;
}
else
{
//get teh current pixel data, and store some of the attributes
//before capping values to fit the encoder type
m_afrgbaSource[uiPixel] = (*pfrgbaSource).ClampRGBA();
if (m_afrgbaSource[uiPixel].fA == 1.0f || m_errormetric == RGBX)
{
m_pimageSource->m_iNumOpaquePixels++;
}
else if (m_afrgbaSource[uiPixel].fA == 0.0f)
{
m_pimageSource->m_iNumTransparentPixels++;
}
else if(m_afrgbaSource[uiPixel].fA > 0.0f && m_afrgbaSource[uiPixel].fA < 1.0f)
{
m_pimageSource->m_iNumTranslucentPixels++;
}
else
{
m_pimageSource->m_numOutOfRangeValues.fA++;
}
if (m_afrgbaSource[uiPixel].fR != 0.0f)
{
m_pimageSource->m_numColorValues.fR++;
//make sure we are getting a float between 0-1
if (m_afrgbaSource[uiPixel].fR - 1.0f > 0.0f)
{
m_pimageSource->m_numOutOfRangeValues.fR++;
}
}
if (m_afrgbaSource[uiPixel].fG != 0.0f)
{
m_pimageSource->m_numColorValues.fG++;
if (m_afrgbaSource[uiPixel].fG - 1.0f > 0.0f)
{
m_pimageSource->m_numOutOfRangeValues.fG++;
}
}
if (m_afrgbaSource[uiPixel].fB != 0.0f)
{
m_pimageSource->m_numColorValues.fB++;
if (m_afrgbaSource[uiPixel].fB - 1.0f > 0.0f)
{
m_pimageSource->m_numOutOfRangeValues.fB++;
}
}
// for formats with no alpha, set source alpha to 1
if (imageformat == Image::Format::ETC1 ||
imageformat == Image::Format::RGB8 ||
imageformat == Image::Format::SRGB8)
{
m_afrgbaSource[uiPixel].fA = 1.0f;
}
if (imageformat == Image::Format::R11 ||
imageformat == Image::Format::SIGNED_R11)
{
m_afrgbaSource[uiPixel].fA = 1.0f;
m_afrgbaSource[uiPixel].fG = 0.0f;
m_afrgbaSource[uiPixel].fB = 0.0f;
}
if (imageformat == Image::Format::RG11 ||
imageformat == Image::Format::SIGNED_RG11)
{
m_afrgbaSource[uiPixel].fA = 1.0f;
m_afrgbaSource[uiPixel].fB = 0.0f;
}
// for RGB8A1, set source alpha to 0.0 or 1.0
// set punch through flag
if (imageformat == Image::Format::RGB8A1 ||
imageformat == Image::Format::SRGB8A1)
{
if (m_afrgbaSource[uiPixel].fA >= 0.5f)
{
m_afrgbaSource[uiPixel].fA = 1.0f;
}
else
{
m_afrgbaSource[uiPixel].fA = 0.0f;
m_boolPunchThroughPixels = true;
}
}
if (m_afrgbaSource[uiPixel].fA == 1.0f || m_errormetric == RGBX)
{
uiOpaqueSourcePixels++;
}
else if (m_afrgbaSource[uiPixel].fA == 0.0f)
{
uiTransparentSourcePixels++;
}
}
uiPixel += 1;
}
}
if (uiOpaqueSourcePixels == PIXELS)
{
m_sourcealphamix = SourceAlphaMix::OPAQUE;
}
else if (uiTransparentSourcePixels == PIXELS)
{
m_sourcealphamix = SourceAlphaMix::TRANSPARENT;
}
else
{
m_sourcealphamix = SourceAlphaMix::TRANSLUCENT;
}
}
// ----------------------------------------------------------------------------------------------------
// return a name for the encoding mode
//
const char * Block4x4::GetEncodingModeName(void)
{
switch (m_pencoding->GetMode())
{
case Block4x4Encoding::MODE_ETC1:
return "ETC1";
case Block4x4Encoding::MODE_T:
return "T";
case Block4x4Encoding::MODE_H:
return "H";
case Block4x4Encoding::MODE_PLANAR:
return "PLANAR";
default:
return "???";
}
}
// ----------------------------------------------------------------------------------------------------
//
}