In short, reading lines of code is most in-efficient method. When dealing with projects with tens of thousands of lines of code, or more (hundred thousand plus), reading and going through the debugger is simply the worst possible way.
Studies have been performed as to what the limits are for the human brain to process information: and it's called the Magical number 7. http://www.musanim.com/miller1956/
Hence, a method must be devised in order to model the large system (i.e. take out key components) and help chunk it to meet this magical number 7 rule.
UML class diagrams are essentially what you need to understand the code. UML is your tool; the unfortunate part is that these diagrams will most likely need to be drawn from hand.
UML class diagrams are a visual tool for building a model of the system; with these, you will be able to at an instant gain an understanding of say a class hierarchy for a given C++ project--such a method is 10x faster than having to read code.
A well designed large software project will start drawing these diagrams from the very beginning, and spent effort updating them.
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In short, reading lines of code is most in-efficient method. When dealing with projects with tens of thousands of lines of code, or more (hundred thousand plus), reading and going through the debugger is simply the worst possible way.
Studies have been performed as to what the limits are for the human brain to process information: and it's called the Magical number 7.
http://www.musanim.com/miller1956/
Hence, a method must be devised in order to model the large system (i.e. take out key components) and help chunk it to meet this magical number 7 rule.
UML class diagrams are essentially what you need to understand the code. UML is your tool; the unfortunate part is that these diagrams will most likely need to be drawn from hand.
UML class diagrams are a visual tool for building a model of the system; with these, you will be able to at an instant gain an understanding of say a class hierarchy for a given C++ project--such a method is 10x faster than having to read code.
A well designed large software project will start drawing these diagrams from the very beginning, and spent effort updating them.