Function RasterizeGradient

trinity/Resources/Procedural/GradientTexture.cpp:141–189

void RasterizeGradient( const std::string_view& path, ImageIO::HostBitmap& bitmap )
{
	bitmap.Destroy();

	if( !IsGradientTexturePath( path ) )
	{
		return;
	}

	auto data = Base64::Decode( std::string_view( path.data() + gradientPrefix.size(), path.size() - gradientPrefix.size() ) );
	if( data.size() < sizeof( Header ) )
	{
		CCP_LOGERR( "Failed to parse dynamic:/gradient_1d/ texture path: the path %s is invalid", std::string( path ).c_str() );
		return;
	}
	Header* header = reinterpret_cast<Header*>( data.data() );
	auto keyCount = header->r.keyCount + header->g.keyCount + header->b.keyCount + header->a.keyCount;
	if( data.size() != sizeof( Header ) + keyCount * sizeof( Tr2CurveScalarKey ) )
	{
		CCP_LOGERR( "Failed to parse dynamic:/gradient_1d/ texture path: the path %s is invalid", std::string( path ).c_str() );
		return;
	}
	if( header->width == 0 )
	{
		CCP_LOGERR( "The texture path %s has texture width of zero: the path is invalid", std::string( path ).c_str() );
		return;
	}
	auto keys = reinterpret_cast<Tr2CurveScalarKey*>( data.data() + sizeof( Header ) );
	Tr2CurveScalarDefinition r = { keys, header->r.keyCount, Tr2CurveExtrapolation::Type( header->r.extrapolationBefore ), Tr2CurveExtrapolation::Type( header->r.extrapolationAfter ) };
	keys += header->r.keyCount;
	Tr2CurveScalarDefinition g = { keys, header->g.keyCount, Tr2CurveExtrapolation::Type( header->g.extrapolationBefore ), Tr2CurveExtrapolation::Type( header->g.extrapolationAfter ) };
	keys += header->g.keyCount;
	Tr2CurveScalarDefinition b = { keys, header->b.keyCount, Tr2CurveExtrapolation::Type( header->b.extrapolationBefore ), Tr2CurveExtrapolation::Type( header->b.extrapolationAfter ) };
	keys += header->b.keyCount;
	Tr2CurveScalarDefinition a = { keys, header->a.keyCount, Tr2CurveExtrapolation::Type( header->a.extrapolationBefore ), Tr2CurveExtrapolation::Type( header->a.extrapolationAfter ) };

	bitmap.Create( header->width, 1, 1, ImageIO::PIXEL_FORMAT_R16G16B16A16_FLOAT );
	auto pixels = reinterpret_cast<Float_16*>( bitmap.GetRawData() );

	CTr2CurveScalar curve;
	curve.SetDefinition( r );
	curve.Rasterize( { header->width, 4, pixels } );
	curve.SetDefinition( g );
	curve.Rasterize( { header->width, 4, pixels + 1 } );
	curve.SetDefinition( b );
	curve.Rasterize( { header->width, 4, pixels + 2 } );
	curve.SetDefinition( a );
	curve.Rasterize( { header->width, 4, pixels + 3 } );
}


bool IsGradientTexturePath( const wchar_t* path )