Method finalize

CesiumVectorData/src/VectorRasterizer.cpp:445–481

}

CesiumUtility::IntrusivePointer<CesiumImage::ImageAsset>
VectorRasterizer::finalize() {
  if (_finalized) {
    return this->_imageAsset;
  }

  this->_context.end();

  // Blend2D writes in BGRA whereas ImageAsset is RGBA.
  // We need to swap the channels to fix the values.
  // Blend2D provides BLPixelConverter for these sorts of operations, which
  // should be faster because it has SIMD support. But the current
  // implementation seems to perform well as-is, likely thanks to the
  // compiler's vectorization.
  std::byte* pData =
      this->_mipLevel == 0
          ? this->_imageAsset->pixelData.data()
          : this->_imageAsset->pixelData.data() +
                this->_imageAsset->mipPositions[this->_mipLevel].byteOffset;
  const size_t size =
      this->_mipLevel == 0
          ? this->_imageAsset->pixelData.size()
          : this->_imageAsset->mipPositions[this->_mipLevel].byteSize;
  for (size_t i = 0; i < size; i += 4) {
    // We need to turn BGRA to RGBA, but this is little endian so it's really
    // ARGB to ABGR.
    uint32_t* pPixel = reinterpret_cast<uint32_t*>(pData + i);
    const uint32_t pixel = *pPixel;
    const uint32_t newPixel =
        (pixel & 0xff000000) | ((pixel & 0x00ff0000) >> 16) |
        (pixel & 0x0000ff00) | ((pixel & 0x000000ff) << 16);
    *pPixel = newPixel;
  }

  this->_finalized = true;
  return this->_imageAsset;
}

} // namespace CesiumVectorData