Program Visualization systems use graphics and animation to represent the behavior of software programs. These systems represent different aspects of the program such as source code, control flow, data structures, runtime state of the program. Representing the actual runtime state of the program finds its use in a variety of applications including program understanding, visual debugging, and pedagogy. However, existing state-of-the-art program visualization systems are limited in : (1) not providing sufficient interactive capabilities to the user; (2) not faithfully representing the runtime state of the program; (3) not allowing users to apply different layout strategies to the visualization; (4) being tied to a specific programming language.

To address these limitations, this thesis presents HDPV, a program state visualization system that visualizes any C, C++, or Java program. HDPV is based on a canonical state model that represents the memory layout of the program as a graph of memory blocks. It decouples the visualization of the program from the actual programming language in which it is written, thereby making the system language independent. HDPV supports a host of interactive features that allow the user to selectively explore different parts of the program's runtime state. Novel layout strategies support customization through user interaction. We provide a list of use-cases to show that HDPV can be applied to a wide variety of applications including - but not limited to - understanding programs that use basic concepts in computer science, demonstrating algorithm implementations, and debugging software programs.