LocalMetricFrame (LMF) Formulation

Mitigating IEEE 754 floating-point cancellation in high-magnitude cartographic reference frames.

The Cartographic Coordinate Challenge

Global projected coordinate systems (such as UTM or Gauss-Boaga) operate with magnitudes reaching 10^6 to 10^7 meters. Under standard IEEE 754 double precision (53-bit mantissa), subtracting close coordinates at large magnitudes induces significant catastrophic cancellation, losing critical precision bits.

Barycentric Local Translation

QismaCAD's architectural design introduces LocalMetricFrame. By translating the computational origin to the geometric centroid of the project boundary, coordinates are normalized to localized metric vectors, preserving numeric conditioning within machine precision.

Local Coordinate Transformation Matrix
P_local = R(theta) * (P_global - P_origin)

Where P_origin is the geometric centroid anchor and R(theta) is the optional boundary orientation tensor.

Planar Topology & Boolean Core

Robust computational geometry primitives designed for land boundary evaluation.

Topological Closure & Orientation

All input rings are normalized to strict counter-clockwise winding for exterior boundaries and clockwise for interior holes. Non-manifold vertices are isolated deterministically.

Exact Boolean Decomposition

Polygon clipping and splitting algorithms operate on planar topological invariants, eliminating zero-area slivers and micro-gap artifacts.

Geodetic & Coordinate Reference Systems

Architectural handling of international and national coordinate datums.

The architecture separates global geodetic anchoring from local metric drafting. Projected coordinates (UTM, Gauss-Boaga, national grid systems) are transformed through rigorous forward/inverse projection models prior to geometric optimization.

Layered Desktop Architecture

High-performance boundary between TypeScript UI and Rust native core.

LEVEL 01 // UI

Presentation Layer (TypeScript)

Lightweight, reactive drafting interface handling user input, visual styling, and AST constraint authoring without blocking computational threads.

LEVEL 02 // BRIDGE

Serialization Bridge (Tauri IPC)

High-throughput binary serialization boundary passing typed commands and geometry buffers between the frontend and native core.

LEVEL 03 // CORE

Computational Core (Rust)

Memory-safe deterministic execution: geometry processing, Delaunay triangulation, and multi-objective Pareto optimization compiled natively.

Design Specification Notice

This technical document details the architectural design and mathematical principles implemented by construction. Official verification and capability status certification reside in the QismaCAD Software repository.