New generation

LESS 3.x

LESS 3.x is the new native implementation of LESS for high-performance radiative-transfer simulation. It uses NVIDIA OptiX, Vulkan Ray Query, and Intel Embree, and supports Windows and Linux. Both LESS 3.x and LESS 2.x are actively maintained, so you can confidently choose either series based on your needs. Install the Python package from PyPI:

pip install less3d LESS 3.x Documentation
Series
Architecture
Distribution
LESS 3.x
OptiX / Vulkan / Embree
PyPI for Windows and Linux
LESS 2.x
Mitsuba-based classic implementation
Downloads listed below

注意:请避免安装在中文路径以及有空格的路径中。
Note: Please avoid installing in a path with spaces.

When using LESS in your work, please cite:

Qi, J., Xie, D., Yin, T., Yan, G., Gastellu-Etchegorry, J.-P., Li, L., Zhang, W., Mu, X., Norford, L.K., 2019b. LESS: LargE-Scale remote sensing data and image simulation framework over heterogeneous 3D scenes. Remote Sensing of Environment 221, 695–706. https://doi.org/10.1016/j.rse.2018.11.036

LESS-2.2.0 (2026.04.05)

Download links

Docker: Search lessrt/less-jupyter in the docker hub to use docker image of LESS, it provides jupyter notebook interface (no GUI).

Updates

English

  • • A new atmosphere radiative transfer module with SunSky model has been integrated, enabling more realistic atmospheric simulation.
  • • The photosynthesis module has been significantly enhanced: turbid medium photosynthesis simulation is now supported, batch processing mode has been added, and overall stability has been improved.
  • • Full Linux support has been added, including updated build scripts, Python 3.12 runtime, and Docker image for containerized deployment.
  • • The Python SDK (pyLessSDK) now supports programmatic scene creation, and module lazy loading has been implemented for faster import times.
  • • The RPV BRDF model now supports multi-band simulation.
  • • GUI batch parameter setting tool has been added for more efficient parameter configuration.
  • • Fixed a memory leak issue caused by sensor/film not being properly released during runtime scene updates.

中文

  • • 新增大气辐射传输模块,集成了SunSky模型,可实现更加真实的大气模拟效果。
  • • 光合作用模块大幅增强:支持浑浊介质光合模拟、新增批处理模式,整体稳定性显著提升。
  • • 全面支持Linux平台,更新了构建脚本,集成Python 3.12运行环境,并提供Docker镜像支持容器化部署。
  • • Python SDK (pyLessSDK) 新增程序化创建场景功能,并实现模块懒加载以加速首次导入速度。
  • • RPV BRDF模型现已支持多波段模拟。
  • • GUI界面新增批量参数设置工具,提高参数配置效率。
  • • 修复了运行时场景更新时sensor/film未正确释放导致的内存泄漏问题。

LESS-2.1.9 (2025.07.25)

Download links

Docker: Search lessrt/less-jupyter in the docker hub to use docker image of LESS, it provides jupyter notebook interface (no GUI).

Updates

English

  • • A new LESS PyCodeEditor has been added, this editor can be used to edit Python code for doing simulations.
  • • It also provides an 'less' object, allowing users to use this object to manipulate the parameters of the GUI.
  • • A new plugin named ReconstructTreeFromPointCloud has been added, this new plugin allows users to reconstruct tree object from single tree point cloud.
  • • A new plugin to generate 3D scenes from urban buiding shapefile.

中文

  • • 新版本中,增加了一个Python代码编辑器LESS PyCodeEditor,在编辑器中可以直接编辑和运行python代码。
  • • 该编辑器提供了一个默认的less对象,基于该对象可以实现对GUI图形界面的参数的控制,以方便利用代码进行批处理和模拟。
  • • 增加了一个新的单木重建插件,利用该插件,可以实现对单木点云重建单木三维结构,输出OBJ文件。
  • • 增加了一个从shapefile文件生成建筑物三维场景的插件。

LESS-2.1.8 (2025.04.12)

Download Links

更新内容

English

  • • The ALS2LESS tool has been upgraded. It now supports individual trees that have been pre-segmented.
  • • The LiDAR simulation module has significantly improved the efficiency of generating pulses.
  • • A mobile LiDAR simulation plugin has been added, which can generate the trajectory of mobile LiDAR.
  • • A forestry inventory plugin has been added, which can automatically extract tree height, diameter at breast height, and other information from forest scenes.
  • • A plugin named ReconstructTreeFromPointCloud has been added for reconstructing tree structures from terrestrial/SLAM LiDAR.
  • • The AutoGUI function with a graphical interface has been added.
  • • The model has been coupled with the Farquar model and others, adding a photosynthesis module.

中文

  • • 新版本中,对于ALS2LESS工具进行了升级,目前支持预先分割好的单木,在las文件中,通过treeID字段来区分不同的单木。
  • • 激光雷达模拟模块,大幅提高了生成pulse的效率,以及增加了TLS模拟时,激光雷达批处理方式。
  • • 添加了一个移动激光雷达模拟插件,可以生成移动激光雷达的路径。
  • • 添加了一个forestryinventory插件,可以对森林场景自动提取树高,胸径等信息。
  • • 添加了从地基/SLAM激光雷达重建树木结构的插件ReconstructTreeFromPointCloud。
  • • 增加了图形界面的AutoGUI功能,即通过在界面输入Python 脚本的方式来控制界面的参数。
  • • 耦合Farquar等模型,增加了光合作用模块,可以实现三维光分布、光合作用的模拟。

LESS-2.1.7 (2024.10.13)

Download Links

更新内容

English

  • • A new Plugin named GenerateSlantedMesh has been added, which genrate simple terrain with slopes.
  • • We have modified the strategy to processing meshes to avoid a double copy of OBJ files.
  • • Some bugs have been fixed.

中文

  • • 新版本中我们增加了一个GenerateSlantedMesh插件,该插件可以产生不同朝向和坡度下的单坡面地形。
  • • 我们该改变了处理OBJ文件的策略,避免了双重复制OBJ文件,这在模拟项目中有大量OBJ文件时节省了大量磁盘空间。
  • • 修复了一些bug。