BlendTwoPosesTogether ( const FCompactPose& SourcePose1, const FCompactPose& SourcePose2, const FBlendedCurve& SourceCurve1, const FBlendedCurve& SourceCurve2, const float WeightOfPose1, FCompactPose& ResultPose, FBlendedCurve& ResultCurve )