Interactive Large‐Scale Procedural Forest Construction and Visualization Based on Particle Flow Simulation

Abstract

Interactive visualization of large forest scenes is challenging due to the large amount of geometric detail that needs to be generated and stored, particularly in scenarios with a moving observer such as forest walkthroughs or overflights. Here, we present a new method for large‐scale procedural forest generation and visualization at interactive rates. We propose a hybrid approach by combining geometry‐based and volumetric modelling techniques with gradually transitioning level of detail (LOD). Nearer trees are constructed using an extended particle flow algorithm, in which particle trails outline the tree ramification in an inverse direction, i.e. from the leaves towards the roots. Reduced geometric representation of a tree is obtained by subsampling the trails. For distant trees, a new volumetric rendering technique in pixel‐space is introduced, which avoids geometry formation altogether and enables visualization of vast forest areas with millions of unique trees. We demonstrate that a GPU‐based implementation of the proposed method provides interactive frame rates in forest overflight scenarios, where new trees are constructed and their LOD adjusted on the fly.

Walking through the forests of the future: using data-driven virtual reality to visualize forests under climate change

“…Plant models can also be created from images (Tan et al 2007, Neubert et al 2007, videos (Li et al 2011) and laser scanning (Zhang et al 2014). Geometry reduction methods have also been proposed given the increasingly complex scenes (Decaudin and Neyret 2009, Neubert et al 2011, Gumbau et al 2011, Zhang et al 2017, Kohek and Strnad 2018. After the generation of 3D models, real-time rendering is required to display the models on screen with realistic lighting, shading, and colors.…”

Data on annotated approximate bilaterally symmetric leaf-off trees based on particle flow simulation and predefined tree crown shape

“…A comparison of new algorithms with the previous work requires good benchmark datasets and trees are typical imperfect natural phenomena and, consequently, a good example for benchmark dataset. The tree models for this data article were generated by the particle flow simulation method [1] , which enables interactive direct shaping of the generated tree crown.…”

“…For all trees, simulation step, , was set to 0.5. Detailed description of parameters is in the original paper of the tree synthesis method [1] .…”

“… tree_[ID]_branch_tips.obj Wavefront OBJ file of 3D branch tips, which contains a set of vertices corresponding to branch tips. The vertices represent the tree crown shape and can be used for placement of leaves [1] or branchlets [2] . tree_[ID].png Screenshot of the tree.…”

Interactive synthesis and visualisation of vast areas with geometrically diverse trees

“…This paper summarises a PhD thesis [2], which proposes a comprehensive pipeline for large-scale synthesis and visualisation of geometrically diverse trees. The main findings are published in the corresponding paper [3]. The following sections summarise the proposed approach, the main results and findings.…”