A Memory-Centric SoC-FPGA Framework for Incremental 2D Delaunay Triangulation
Xuefei Huang, Zihan Zhang, Kyriakos M. DeliparaschosIncremental two-dimensional (2D) Delaunay triangulation is a fundamental operation in point-cloud processing and surface reconstruction, yet its irregular memory access and dynamically evolving topology make efficient hardware implementation difficult. Conventional point-location strategies validate many candidate triangles, limiting efficiency on resource-constrained embedded platforms. This paper presents a unified System-on-Chip Field-Programmable Gate Array (SoC-FPGA) framework that instantiates two design points: an acceleration-oriented variant that lowers latency for small-to-medium inputs and a scalability-oriented variant that extends input capacity. Both share a common backbone: a Doubly Connected Edge List (DCEL) topology, a structure-of-arrays memory layout with heterogeneous on-chip binding, a Hilbert-ordered insertion sequence, and a grid-assisted scheme that turns global point location into a bounded local search. Implemented on the AMD Kria KR260, the deployed PS–PL system executes the Delaunay triangulation in the programmable logic, while the ARM Cortex-A53 processor manages accelerator control, data transfer, and end-to-end timing. For a 6000-point input, the acceleration-oriented variant requires 482.25 ms in RTL co-simulation, corresponding to a 32.7× speedup over the same-flow Vitis C-simulation reference on an Intel workstation. Its measured PS–PL end-to-end runtime is 315.919±0.042 ms, achieving a 1.96× speedup over a CPU-only Cortex-A53 implementation on the same KR260 platform and a separately reported 50.0× speedup over the workstation Vitis C-simulation reference. The scalability-oriented variant completes the same input in 868.51 ms and reduces the point-location fallback rate from 12.6% to 2.9%. On a 16,000-point set that exceeds the acceleration-oriented variant’s on-chip budget, it finishes in 4360.6 ms in RTL co-simulation, corresponding to a 19.0× speedup over its same-flow workstation Vitis C-simulation reference. The framework thus provides explicit, tunable trade-offs between latency and scalability within a single architectural template, offering a practical solution for embedded geometric preprocessing.