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nvidia-texture-tools/src/nvtt/CompressDXT.cpp

676 lines
20 KiB
C++

// Copyright NVIDIA Corporation 2007 -- Ignacio Castano <icastano@nvidia.com>
//
// Permission is hereby granted, free of charge, to any person
// obtaining a copy of this software and associated documentation
// files (the "Software"), to deal in the Software without
// restriction, including without limitation the rights to use,
// copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following
// conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
// OTHER DEALINGS IN THE SOFTWARE.
#include "CompressDXT.h"
#include "QuickCompressDXT.h"
#include "OptimalCompressDXT.h"
#include "CompressionOptions.h"
#include "OutputOptions.h"
// squish
#include "squish/colourset.h"
#include "squish/fastclusterfit.h"
#include "squish/weightedclusterfit.h"
#include <nvtt/nvtt.h>
#include <nvcore/Memory.h>
#include <nvimage/Image.h>
#include <nvimage/ColorBlock.h>
#include <nvimage/BlockDXT.h>
// s3_quant
#if defined(HAVE_S3QUANT)
#include "s3tc/s3_quant.h"
#endif
// ati tc
#if defined(HAVE_ATITC)
typedef int BOOL;
typedef _W64 unsigned long ULONG_PTR;
typedef ULONG_PTR DWORD_PTR;
#include "atitc/ATI_Compress.h"
#endif
// squish
#if defined(HAVE_SQUISH)
//#include "squish/squish.h"
#include "squish-1.10/squish.h"
#endif
// d3dx
#if defined(HAVE_D3DX)
#include <d3dx9.h>
#endif
// stb
#if defined(HAVE_STB)
#define STB_DEFINE
#include "stb/stb_dxt.h"
#endif
#pragma message(NV_FILE_LINE "FIXME: Define HAVE_OPENMP from cmake.")
#define HAVE_OPENMP
#include <omp.h>
using namespace nv;
using namespace nvtt;
void FixedBlockCompressor::compress(nvtt::InputFormat inputFormat, nvtt::AlphaMode alphaMode, uint w, uint h, void * data, const nvtt::CompressionOptions::Private & compressionOptions, const nvtt::OutputOptions::Private & outputOptions)
{
const uint bs = blockSize();
const uint bw = (w + 3) / 4;
const uint bh = (h + 3) / 4;
const uint size = bs * bw * bh;
#if defined(HAVE_OPENMP)
bool singleThreaded = false;
#else
bool singleThreaded = true;
#endif
// Use a single thread to compress small textures.
if (bw * bh < 16) singleThreaded = true;
if (singleThreaded)
{
nvDebugCheck(bs <= 16);
uint8 mem[16];
for (int y = 0; y < int(h); y += 4) {
for (uint x = 0; x < w; x += 4) {
ColorBlock rgba;
if (inputFormat == nvtt::InputFormat_BGRA_8UB) {
rgba.init(w, h, (uint *)data, x, y);
}
else {
nvDebugCheck(inputFormat == nvtt::InputFormat_RGBA_32F);
rgba.init(w, h, (float *)data, x, y);
}
compressBlock(rgba, alphaMode, compressionOptions, mem);
if (outputOptions.outputHandler != NULL) {
outputOptions.outputHandler->writeData(mem, bs);
}
}
}
}
#if defined(HAVE_OPENMP)
else
{
uint8 * mem = new uint8[size];
#pragma omp parallel
{
#pragma omp for
for (int i = 0; i < int(bw*bh); i++)
{
const uint x = i % bw;
const uint y = i / bw;
ColorBlock rgba;
if (inputFormat == nvtt::InputFormat_BGRA_8UB) {
rgba.init(w, h, (uint *)data, 4*x, 4*y);
}
else {
nvDebugCheck(inputFormat == nvtt::InputFormat_RGBA_32F);
rgba.init(w, h, (float *)data, 4*x, 4*y);
}
uint8 * ptr = mem + (y * bw + x) * bs;
compressBlock(rgba, alphaMode, compressionOptions, ptr);
} // omp for
} // omp parallel
if (outputOptions.outputHandler != NULL) {
outputOptions.outputHandler->writeData(mem, size);
}
delete [] mem;
}
#endif
}
void FastCompressorDXT1::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockDXT1 * block = new(output) BlockDXT1;
QuickCompress::compressDXT1(rgba, block);
}
void FastCompressorDXT1a::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockDXT1 * block = new(output) BlockDXT1;
QuickCompress::compressDXT1a(rgba, block);
}
void FastCompressorDXT3::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockDXT3 * block = new(output) BlockDXT3;
QuickCompress::compressDXT3(rgba, block);
}
void FastCompressorDXT5::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockDXT5 * block = new(output) BlockDXT5;
QuickCompress::compressDXT5(rgba, block);
}
void FastCompressorDXT5n::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
rgba.swizzle(4, 1, 5, 0); // 0xFF, G, 0, R
BlockDXT5 * block = new(output) BlockDXT5;
QuickCompress::compressDXT5(rgba, block);
}
void FastCompressorBC4::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockATI1 * block = new(output) BlockATI1;
rgba.swizzle(0, 1, 2, 0); // Copy red to alpha
QuickCompress::compressDXT5A(rgba, &block->alpha);
}
void FastCompressorBC5::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockATI2 * block = new(output) BlockATI2;
rgba.swizzle(0, 1, 2, 0); // Copy red to alpha
QuickCompress::compressDXT5A(rgba, &block->x);
rgba.swizzle(0, 1, 2, 1); // Copy green to alpha
QuickCompress::compressDXT5A(rgba, &block->y);
}
void NormalCompressorDXT1::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
nvsquish::WeightedClusterFit fit;
fit.SetMetric(compressionOptions.colorWeight.x(), compressionOptions.colorWeight.y(), compressionOptions.colorWeight.z());
if (rgba.isSingleColor())
{
BlockDXT1 * block = new(output) BlockDXT1;
OptimalCompress::compressDXT1(rgba.color(0), block);
}
else
{
nvsquish::ColourSet colours((uint8 *)rgba.colors(), 0);
fit.SetColourSet(&colours, nvsquish::kDxt1);
fit.Compress(output);
}
}
void NormalCompressorDXT1a::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
bool anyAlpha = false;
bool allAlpha = true;
for (uint i = 0; i < 16; i++)
{
if (rgba.color(i).a < 128) anyAlpha = true;
else allAlpha = false;
}
const bool isSingleColor = rgba.isSingleColor();
if ((!anyAlpha && isSingleColor || allAlpha))
{
BlockDXT1 * block = new(output) BlockDXT1;
OptimalCompress::compressDXT1a(rgba.color(0), block);
}
else
{
nvsquish::WeightedClusterFit fit;
fit.SetMetric(compressionOptions.colorWeight.x(), compressionOptions.colorWeight.y(), compressionOptions.colorWeight.z());
int flags = nvsquish::kDxt1;
if (alphaMode == nvtt::AlphaMode_Transparency) flags |= nvsquish::kWeightColourByAlpha;
nvsquish::ColourSet colours((uint8 *)rgba.colors(), flags);
fit.SetColourSet(&colours, nvsquish::kDxt1);
fit.Compress(output);
}
}
void NormalCompressorDXT3::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockDXT3 * block = new(output) BlockDXT3;
// Compress explicit alpha.
OptimalCompress::compressDXT3A(rgba, &block->alpha);
// Compress color.
if (rgba.isSingleColor())
{
OptimalCompress::compressDXT1(rgba.color(0), &block->color);
}
else
{
nvsquish::WeightedClusterFit fit;
fit.SetMetric(compressionOptions.colorWeight.x(), compressionOptions.colorWeight.y(), compressionOptions.colorWeight.z());
int flags = 0;
if (alphaMode == nvtt::AlphaMode_Transparency) flags |= nvsquish::kWeightColourByAlpha;
nvsquish::ColourSet colours((uint8 *)rgba.colors(), flags);
fit.SetColourSet(&colours, 0);
fit.Compress(&block->color);
}
}
void NormalCompressorDXT5::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockDXT5 * block = new(output) BlockDXT5;
// Compress alpha.
if (compressionOptions.quality == Quality_Highest)
{
OptimalCompress::compressDXT5A(rgba, &block->alpha);
}
else
{
QuickCompress::compressDXT5A(rgba, &block->alpha);
}
// Compress color.
if (rgba.isSingleColor())
{
OptimalCompress::compressDXT1(rgba.color(0), &block->color);
}
else
{
nvsquish::WeightedClusterFit fit;
fit.SetMetric(compressionOptions.colorWeight.x(), compressionOptions.colorWeight.y(), compressionOptions.colorWeight.z());
int flags = 0;
if (alphaMode == nvtt::AlphaMode_Transparency) flags |= nvsquish::kWeightColourByAlpha;
nvsquish::ColourSet colours((uint8 *)rgba.colors(), flags);
fit.SetColourSet(&colours, 0);
fit.Compress(&block->color);
}
}
void NormalCompressorDXT5n::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
rgba.swizzle(4, 1, 5, 0); // 0xFF, G, 0, R
BlockDXT5 * block = new(output) BlockDXT5;
// Compress X.
if (compressionOptions.quality == Quality_Highest)
{
OptimalCompress::compressDXT5A(rgba, &block->alpha);
}
else
{
QuickCompress::compressDXT5A(rgba, &block->alpha);
}
// Compress Y.
if (compressionOptions.quality == Quality_Highest)
{
OptimalCompress::compressDXT1G(rgba, &block->color);
}
else
{
if (rgba.isSingleColor())
{
OptimalCompress::compressDXT1G(rgba.color(0), &block->color);
}
else
{
nvsquish::WeightedClusterFit fit;
fit.SetMetric(0, 1, 0);
int flags = 0;
if (alphaMode == nvtt::AlphaMode_Transparency) flags |= nvsquish::kWeightColourByAlpha;
nvsquish::ColourSet colours((uint8 *)rgba.colors(), flags);
fit.SetColourSet(&colours, 0);
fit.Compress(&block->color);
}
}
}
void ProductionCompressorBC4::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockATI1 * block = new(output) BlockATI1;
rgba.swizzle(0, 1, 2, 0); // Copy red to alpha
OptimalCompress::compressDXT5A(rgba, &block->alpha);
}
void ProductionCompressorBC5::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
BlockATI2 * block = new(output) BlockATI2;
rgba.swizzle(0, 1, 2, 0); // Copy red to alpha
OptimalCompress::compressDXT5A(rgba, &block->x);
rgba.swizzle(0, 1, 2, 1); // Copy green to alpha
OptimalCompress::compressDXT5A(rgba, &block->y);
}
#if defined(HAVE_S3QUANT)
void S3CompressorDXT1::compress(nvtt::InputFormat inputFormat, nvtt::AlphaMode alphaMode, uint w, uint h, void * data, const nvtt::CompressionOptions::Private & compressionOptions, const nvtt::OutputOptions::Private & outputOptions)
{
float error = 0.0f;
BlockDXT1 dxtBlock3;
BlockDXT1 dxtBlock4;
ColorBlock block;
for (uint y = 0; y < h; y += 4) {
for (uint x = 0; x < w; x += 4) {
block.init(inputFormat, w, h, data, x, y);
// Init rgb block.
RGBBlock rgbBlock;
rgbBlock.n = 16;
for (uint i = 0; i < 16; i++) {
rgbBlock.colorChannel[i][0] = clamp(float(block.color(i).r) / 255.0f, 0.0f, 1.0f);
rgbBlock.colorChannel[i][1] = clamp(float(block.color(i).g) / 255.0f, 0.0f, 1.0f);
rgbBlock.colorChannel[i][2] = clamp(float(block.color(i).b) / 255.0f, 0.0f, 1.0f);
}
rgbBlock.weight[0] = 1.0f;
rgbBlock.weight[1] = 1.0f;
rgbBlock.weight[2] = 1.0f;
rgbBlock.inLevel = 4;
CodeRGBBlock(&rgbBlock);
// Copy results to DXT block.
dxtBlock4.col0.r = rgbBlock.endPoint[0][0];
dxtBlock4.col0.g = rgbBlock.endPoint[0][1];
dxtBlock4.col0.b = rgbBlock.endPoint[0][2];
dxtBlock4.col1.r = rgbBlock.endPoint[1][0];
dxtBlock4.col1.g = rgbBlock.endPoint[1][1];
dxtBlock4.col1.b = rgbBlock.endPoint[1][2];
dxtBlock4.setIndices(rgbBlock.index);
if (dxtBlock4.col0.u < dxtBlock4.col1.u) {
swap(dxtBlock4.col0.u, dxtBlock4.col1.u);
dxtBlock4.indices ^= 0x55555555;
}
uint error4 = blockError(block, dxtBlock4);
rgbBlock.inLevel = 3;
CodeRGBBlock(&rgbBlock);
// Copy results to DXT block.
dxtBlock3.col0.r = rgbBlock.endPoint[0][0];
dxtBlock3.col0.g = rgbBlock.endPoint[0][1];
dxtBlock3.col0.b = rgbBlock.endPoint[0][2];
dxtBlock3.col1.r = rgbBlock.endPoint[1][0];
dxtBlock3.col1.g = rgbBlock.endPoint[1][1];
dxtBlock3.col1.b = rgbBlock.endPoint[1][2];
dxtBlock3.setIndices(rgbBlock.index);
if (dxtBlock3.col0.u > dxtBlock3.col1.u) {
swap(dxtBlock3.col0.u, dxtBlock3.col1.u);
dxtBlock3.indices ^= (~dxtBlock3.indices >> 1) & 0x55555555;
}
uint error3 = blockError(block, dxtBlock3);
if (error3 < error4) {
error += error3;
if (outputOptions.outputHandler != NULL) {
outputOptions.outputHandler->writeData(&dxtBlock3, sizeof(dxtBlock3));
}
}
else {
error += error4;
if (outputOptions.outputHandler != NULL) {
outputOptions.outputHandler->writeData(&dxtBlock4, sizeof(dxtBlock4));
}
}
}
}
}
#endif // defined(HAVE_S3QUANT)
#if defined(HAVE_ATITC)
void AtiCompressorDXT1::compress(nvtt::InputFormat inputFormat, nvtt::AlphaMode alphaMode, uint w, uint h, void * data, const nvtt::CompressionOptions::Private & compressionOptions, const nvtt::OutputOptions::Private & outputOptions)
{
// Init source texture
ATI_TC_Texture srcTexture;
srcTexture.dwSize = sizeof(srcTexture);
srcTexture.dwWidth = w;
srcTexture.dwHeight = h;
if (inputFormat == nvtt::InputFormat_BGRA_8UB)
{
srcTexture.dwPitch = w * 4;
srcTexture.format = ATI_TC_FORMAT_ARGB_8888;
}
else
{
srcTexture.dwPitch = w * 16;
srcTexture.format = ATI_TC_FORMAT_ARGB_32F;
}
srcTexture.dwDataSize = ATI_TC_CalculateBufferSize(&srcTexture);
srcTexture.pData = (ATI_TC_BYTE*) data;
// Init dest texture
ATI_TC_Texture destTexture;
destTexture.dwSize = sizeof(destTexture);
destTexture.dwWidth = w;
destTexture.dwHeight = h;
destTexture.dwPitch = 0;
destTexture.format = ATI_TC_FORMAT_DXT1;
destTexture.dwDataSize = ATI_TC_CalculateBufferSize(&destTexture);
destTexture.pData = (ATI_TC_BYTE*) mem::malloc(destTexture.dwDataSize);
ATI_TC_CompressOptions options;
options.dwSize = sizeof(options);
options.bUseChannelWeighting = false;
options.bUseAdaptiveWeighting = false;
options.bDXT1UseAlpha = false;
options.nCompressionSpeed = ATI_TC_Speed_Normal;
options.bDisableMultiThreading = false;
//options.bDisableMultiThreading = true;
// Compress
ATI_TC_ConvertTexture(&srcTexture, &destTexture, &options, NULL, NULL, NULL);
if (outputOptions.outputHandler != NULL) {
outputOptions.outputHandler->writeData(destTexture.pData, destTexture.dwDataSize);
}
mem::free(destTexture.pData);
}
void AtiCompressorDXT5::compress(nvtt::InputFormat inputFormat, nvtt::AlphaMode alphaMode, uint w, uint h, void * data, const nvtt::CompressionOptions::Private & compressionOptions, const nvtt::OutputOptions::Private & outputOptions)
{
// Init source texture
ATI_TC_Texture srcTexture;
srcTexture.dwSize = sizeof(srcTexture);
srcTexture.dwWidth = w;
srcTexture.dwHeight = h;
if (inputFormat == nvtt::InputFormat_BGRA_8UB)
{
srcTexture.dwPitch = w * 4;
srcTexture.format = ATI_TC_FORMAT_ARGB_8888;
}
else
{
srcTexture.dwPitch = w * 16;
srcTexture.format = ATI_TC_FORMAT_ARGB_32F;
}
srcTexture.dwDataSize = ATI_TC_CalculateBufferSize(&srcTexture);
srcTexture.pData = (ATI_TC_BYTE*) data;
// Init dest texture
ATI_TC_Texture destTexture;
destTexture.dwSize = sizeof(destTexture);
destTexture.dwWidth = w;
destTexture.dwHeight = h;
destTexture.dwPitch = 0;
destTexture.format = ATI_TC_FORMAT_DXT5;
destTexture.dwDataSize = ATI_TC_CalculateBufferSize(&destTexture);
destTexture.pData = (ATI_TC_BYTE*) mem::malloc(destTexture.dwDataSize);
// Compress
ATI_TC_ConvertTexture(&srcTexture, &destTexture, NULL, NULL, NULL, NULL);
if (outputOptions.outputHandler != NULL) {
outputOptions.outputHandler->writeData(destTexture.pData, destTexture.dwDataSize);
}
mem::free(destTexture.pData);
}
#endif // defined(HAVE_ATITC)
#if defined(HAVE_SQUISH)
void SquishCompressorDXT1::compress(nvtt::InputFormat inputFormat, nvtt::AlphaMode alphaMode, uint w, uint h, void * data, const nvtt::CompressionOptions::Private & compressionOptions, const nvtt::OutputOptions::Private & outputOptions)
{
#pragma message(NV_FILE_LINE "TODO: Convert input to fixed point ABGR format instead of ARGB")
/*
Image img(*image);
int count = img.width() * img.height();
for (int i = 0; i < count; i++)
{
Color32 c = img.pixel(i);
img.pixel(i) = Color32(c.b, c.g, c.r, c.a);
}
int size = squish::GetStorageRequirements(img.width(), img.height(), squish::kDxt1);
void * blocks = mem::malloc(size);
squish::CompressImage((const squish::u8 *)img.pixels(), img.width(), img.height(), blocks, squish::kDxt1 | squish::kColourClusterFit);
if (outputOptions.outputHandler != NULL) {
outputOptions.outputHandler->writeData(blocks, size);
}
mem::free(blocks);
*/
}
#endif // defined(HAVE_SQUISH)
#if defined(HAVE_D3DX)
void D3DXCompressorDXT1::compress(nvtt::InputFormat inputFormat, nvtt::AlphaMode alphaMode, uint w, uint h, void * data, const nvtt::CompressionOptions::Private & compressionOptions, const nvtt::OutputOptions::Private & outputOptions)
{
IDirect3D9 * d3d = Direct3DCreate9(D3D_SDK_VERSION);
D3DPRESENT_PARAMETERS presentParams;
ZeroMemory(&presentParams, sizeof(presentParams));
presentParams.Windowed = TRUE;
presentParams.SwapEffect = D3DSWAPEFFECT_COPY;
presentParams.BackBufferWidth = 8;
presentParams.BackBufferHeight = 8;
presentParams.BackBufferFormat = D3DFMT_UNKNOWN;
HRESULT err;
IDirect3DDevice9 * device = NULL;
err = d3d->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_REF, GetDesktopWindow(), D3DCREATE_SOFTWARE_VERTEXPROCESSING, &presentParams, &device);
IDirect3DTexture9 * texture = NULL;
err = D3DXCreateTexture(device, w, h, 1, 0, D3DFMT_DXT1, D3DPOOL_SYSTEMMEM, &texture);
IDirect3DSurface9 * surface = NULL;
err = texture->GetSurfaceLevel(0, &surface);
RECT rect;
rect.left = 0;
rect.top = 0;
rect.bottom = h;
rect.right = w;
if (inputFormat == nvtt::InputFormat_BGRA_8UB)
{
err = D3DXLoadSurfaceFromMemory(surface, NULL, NULL, data, D3DFMT_A8R8G8B8, w * 4, NULL, &rect, D3DX_DEFAULT, 0);
}
else
{
err = D3DXLoadSurfaceFromMemory(surface, NULL, NULL, data, D3DFMT_A32B32G32R32F, w * 16, NULL, &rect, D3DX_DEFAULT, 0);
}
if (err != D3DERR_INVALIDCALL && err != D3DXERR_INVALIDDATA)
{
D3DLOCKED_RECT rect;
ZeroMemory(&rect, sizeof(rect));
err = surface->LockRect(&rect, NULL, D3DLOCK_READONLY);
if (outputOptions.outputHandler != NULL) {
int size = rect.Pitch * ((h + 3) / 4);
outputOptions.outputHandler->writeData(rect.pBits, size);
}
err = surface->UnlockRect();
}
surface->Release();
device->Release();
d3d->Release();
}
#endif // defined(HAVE_D3DX)
#if defined(HAVE_STB)
void StbCompressorDXT1::compressBlock(ColorBlock & rgba, nvtt::AlphaMode alphaMode, const nvtt::CompressionOptions::Private & compressionOptions, void * output)
{
rgba.swizzle(2, 1, 0, 3); // Swap R and B
stb_compress_dxt_block((unsigned char *)output, (unsigned char *)rgba.colors(), 0, 0);
}
#endif // defined(HAVE_STB)