DISCUSSION
The
ATSUOverwriteAttributes function copies style run attributes, font features, and font variations that were previously set in the source style object into the destination style object, regardless of whether or not these values are set in the destination style object. All other quantities in the destination style object are left unchanged.
ATSUOverwriteAttributes does not copy the contents of memory referenced by pointers or handles within custom style run attributes or within reference constants. You are responsible for ensuring that this memory remains valid until the source style object is disposed of.
To create a copy of the entire contents of a style object, call the function
ATSUCreateAndCopyStyle. If you wish to copy the entire contents of a style object into an existing style object, you should call the function
ATSUCopyAttributes. To copy only those style run attributes, font features, and font variations that were previously set in the source style object but not set in the destination style object, call the function
ATSUUnderwriteAttributes.