The Metric View can now display a second metric by coloring the treemap elements. Hence two code metrics can be displayed at once.
For example by setting Size metric to number of lines of code vs. Color metric to percentage code coverage, we can get a global, yet accurate, view of where the code base is not enough covered by tests.
The screenshots below shows the CppDepend v6 code base, 160K Lines of Code 82% covered by tests. We know at a glance where we've been good and where more tests effort should be spent.
By choosing adequate pairs of metrics, many other insightful views can be obtained, relative to code quality, code flaws, code structure, code diff...
Coloring can be customized and custom code metrics, defined through CQLinq querying, can be displayed as well as size or color metric.