虚拟激光扫描与 HELIOS++：基于光线追踪的地形三维激光扫描模拟的新方法
Virtual laser scanning with HELIOS++: A novel take on ray tracing-based simulation of topographic 3D laser scanning
AI总结：
本文提出开源模拟框架 HELIOS++，基于光线追踪模拟地形三维激光扫描，支持多种平台，通过灵活配置平衡物理精度与计算效率，显著降低运行时间和内存需求。
摘要：
地形激光扫描是一种遥感方法，用于生成地球表面的详细三维点云表示。由于数据采集成本高昂，在满足特定前提条件的情况下，模拟可以补充真实数据：i) 三维场景和扫描仪的模型，ii) 光束-场景相互作用的模型，简化到计算上可行且物理上逼真的水平，以及 iii) 模拟数据适用的应用场景。目前存在多种用于不同目的的激光扫描模拟器，我们通过介绍 HELIOS++ 来丰富这一领域。HELIOS++ 是一个开源模拟框架，用于地面静态、移动、无人机载和机载激光扫描，采用 C++ 实现。HELIOS++ 的概念为物理精度（逼真度）与计算复杂度（运行时间、内存占用）之间的权衡，以及易用性和易配置性提供了灵活的解决方案。HELIOS++ 的独特功能包括提供 Python 绑定（pyhelios）以控制模拟，以及多种用于三维场景表示的模型类型。HELIOS++ 还允许使用子采样策略模拟光束发散，并能够生成全波形输出，作为详细分析的基础。由于波形的生成和分析可能对运行时间产生显著影响，用户可以设置子采样的细节级别，或选择完全禁用全波形输出。对计算方面的详细评估以及 HELIOS++ 与其前身 HELIOS 的比较显示，运行时间最多可减少 83%。同时，内存需求最多可减少 94%，从而允许将更大（即更复杂）的三维场景加载到内存中，进而通过激光扫描模拟进行虚拟采集。
英文摘要：
Topographic laser scanning is a remote sensing method to create detailed 3D point cloud representations of the Earth's surface. Since data acquisition is expensive, simulations can complement real data given certain premises are available: i) a model of 3D scene and scanner, ii) a model of the beam-scene interaction, simplified to a computationally feasible while physically realistic level, and iii) an application for which simulated data is fit for use. A number of laser scanning simulators for different purposes exist, which we enrich by presenting HELIOS++. HELIOS++ is an open-source simulation framework for terrestrial static, mobile, UAV-based and airborne laser scanning implemented in C++. The HELIOS++ concept provides a flexible solution for the trade-off between physical accuracy (realism) and computational complexity (runtime, memory footprint), as well as ease of use and of configuration. Unique features of HELIOS++ include the availability of Python bindings (pyhelios) for controlling simulations, and a range of model types for 3D scene representation. HELIOS++ further allows the simulation of beam divergence using a subsampling strategy, and is able to create full-waveform outputs as a basis for detailed analysis. As generation and analysis of waveforms can strongly impact runtimes, the user may set the level of detail for the subsampling, or optionally disable full-waveform output altogether. A detailed assessment of computational considerations and a comparison of HELIOS++ to its predecessor, HELIOS, reveal reduced runtimes by up to 83 %. At the same time, memory requirements are reduced by up to 94 %, allowing for much larger (i.e. more complex) 3D scenes to be loaded into memory and hence to be virtually acquired by laser scanning simulation.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
