1. A method of visualizing tree-structured data on a display using an aggregation approach that allows for a dynamic, interactive, adaptive level-of-detail for 2D, 2.5D, and/or 3D treemaps, including: receiving layed-out tree-structured data including encoded node positions and extents; traversing dependent attributes to accumulate attributes using a use-case specific accumulation operator in the tree-structured data; identifying aggregates by interactive scoring of each node in the tree-structured data based on contextual relevance and other criteria including at least one of changes in attributes, focus, or view of the tree-structured data based on task, interaction, visibility, processing budget, and/or performance specific criteria; mapping and rendering the identified aggregates as a per-frame aggregation of blocks and accumulation of attributes mapped to visual variables; and presenting the aggregated blocks to a display while visually preserving important data conveyed by tree-structured elements and their mapped attributes based on a specified mapping theme for the tree-structured data.