Now that Sixel and iTerm2 bitmap image formats are supported, there is some optimization and bug-fixing to do. (By the way, the bitmaps also work in the experimental new Retina terminals.)
Work is being done to allocate an appropriate number of terminal columns to each “grapheme cluster”, instead of assuming that everything will occupy the same space as a Roman letter.
Note that this will be much more sophisticated than the double-size-line sequences from the VT-series terminals (already supported): column widths will be able to vary throughout the line and they will not be limited to just single or double.
It is important to note that this initial set of changes will affect the arrangement of text but not the font behavior or other rendering. This means that if MacTerm currently fails to render text from a particular language, it will probably still fail to render that text in the new layout system (though the line will now be spaced properly for future use by an improved renderer).
Work is also being done to correctly store Unicode text in every possible situation. For instance, MacTerm currently cannot handle “high plane” values because it internally stores only one 16-bit code per terminal column.
After the improvements to text storage, virtually all text will be stored correctly. This means that any attempt to use the text (such as Copy or Print) will have no issues, even with so-called “high plane” Unicode sequences.
It is important to note that rendering is a separate issue so improved text storage will not necessarily improve rendering, except in cases where text is used outside the terminal view (like the Clipboard, Print Preview, and using Paste in other applications).
The primary terminal “view” is being updated to support Cocoa and Core Graphics natively. This will make text look outstanding on Retina displays, and terminals will integrate better with other OS features such as Full Screen mode. This is also the last component keeping the project from dropping legacy OS frameworks so future development will be greatly accelerated!
The new terminal view is already being used by the “samples” in Format panes (with a few display bugs that are being fixed). The downside of this early adoption is that in the short term, the sample is not very accurate; it can portray fonts and even colors in a way that is significantly different than the legacy terminal.