Search arXivSearch

arXiv · 2508.08561

Revisiting the City Tower Project: Geometric Principles and Structural Morphology in the Works of Louis I. Kahn and Anne Tyng

Abstract

This paper presents a study of computation and morphology of Louis Kahn City Tower project. The City Tower is an unbuilt design by Louis I. Kahn and Anne Tyng that integrates form and structure using 3D space triangular geometries. Although never built, the City Tower geometrical framework anticipated later developments in design of space-frame structures. Initially envisioned in the 1950s, the City Tower project is a skyscraper structure based on a tetrahedral and octahedral space frame called Octet-Truss. The aim of this study is to analyze the geometry of the City Tower structure and how it can be used to develop modular and adaptable architectural forms. The study is based on an analytical shape grammar that is used to recreate the original structure, and later to generate new structural configurations based on the City Tower's morphology. This study also investigates the potential applications of these findings in architecture and reveals the possibilities of using tetrahedrons and octahedrons as fundamental geometries for creating scalable and modular designs and presents initial findings.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Aysan Mokhtarimousavi, Michael Kleiss, Mostafa Alani, Sida Dai. 2025-08-12. Revisiting the City Tower Project: Geometric Principles and Structural Morphology in the Works of Louis I. Kahn and Anne Tyng. https://arxiv.org/abs/2508.08561

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Opacity Is Not Just Opacity

Web graphics travel with content across pages and themes, where changing backgrounds can require recoloring and maintenance. Opacity already makes a fixed object's appearance depend on its background, yet is usually understood only as how much the object obscures it. In fact, opacity controls the scaling of the object-background color difference; transparency is only one effect of this relationship. Zero places the output at the background and one at the source color, but difference scaling need not stop at either position. We retain the compositing expression and extend the coefficient domain from $[0,1]$ to the real numbers: negative values reverse the difference, whereas values above one expand it in the same direction. We focus on same-direction expansion for reusing Web graphics across backgrounds. Each object carries a fixed source color and coefficient, while the actual background determines the enhancement direction. Background-adaptive contrast enhancement thus becomes part of the object's compositing properties, reducing the design and maintenance of separate color variants. The implementation reuses the original equation without increasing the per-pixel arithmetic operation count within the same pipeline. Enumerating all 8-bit sRGB source colors on 16 predefined light and dark canvases, a fixed $α=1.1$ increases the contrast ratio in 99.8145% of combinations. Without changing source colors, 4.8346% of all combinations newly reach the $3:1$ contrast threshold. Output validation and timing across three browsers demonstrate implementation in the same WebGL pipeline, with no sustained additional runtime observed.

cs.GR

Constrained Program Generation for 3D Reaction Animation with a 0.8B Model

Visualizing a chemical reaction requires making its molecular changes visible while keeping the animation faithful to the stated chemistry. Equations, structural diagrams and molecular viewers provide complementary descriptions, but assembling an interactive three-dimensional explanation still requires specifying the changes and checking their consistency. We present ChemXRG, a domain-specific language (DSL) framework that addresses this gap by representing a reaction animation as an executable program. Persistent atom identifiers and explicit bond, charge and grouping operations connect the symbolic reaction to the displayed transformation. This shared representation lets generation, verification and rendering operate on the same account of what changes. Given known, atom-mapped reactant and product structures, reaction-grounded constraints fix input-determined facts and restrict action choices; execution checks validate the resulting transformation before geometry and frames are constructed. We implement this paradigm with a reaction-program corpus and ChemQwen, a trained 0.8B DSL generator. Paired and component evaluations show improved compiler acceptance and normalized full-program agreement under input-conditioned constraints, while identifying remaining failures that require execution checks. A public browser application demonstrates the connection from symbolic reaction descriptions to inspectable programs and interactive 3D animations.

cs.GR

NaRPA: Navigation and Rendering Pipeline for Astronautics

This paper presents the applications of scientific ray-tracing in modeling and simulating light transport for space-borne image data generation. A ray-tracing engine, the Navigation and Rendering Pipeline for Astronautics (NaRPA), is introduced as a rendering framework to generate virtual datasets and support simulations for robust navigation pipelines. Sensor and environment models that enable the synthesis of space-to-space and ground-to-space virtual observations are presented. The work demonstrates the capabilities of simulating passive and active vision-based sensors using NaRPA to facilitate the design, testing, and verification of aerospace visual navigation algorithms. Additionally, the paper describes a velocimeter LiDAR model and its statistical validation with experimental data.

cs.GR