中文摘要：

为了解决传统方法中存在的三维树木交互式修剪问题，提出一种基于颜色编码的虚拟树木交互式快速修剪方法．首先分析了虚拟树木交互式修剪技术的要求和存在的困难；然后依托自主开发的基于形态特征参数的三维树木建模系统ParaTree，提出一种结合树木层级拓扑结构的快速拾取海量图元的方法，将树木三维模型巧妙地编码为32位RGBA颜色，并利用GPU上的离屏缓冲区实现了基于颜色编码的交互式枝条修剪．实验结果表明，该方法具有普适性，易于与其他植物建模方法结合，扩展了树木三维建模与可视化系统的基本功能，具有像素级的拾取精度和独立于模型复杂度的非常快速的响应时间，为树木栽培和经营管理的株型设计或整枝修剪的数字化设计研究提供了新的手段．

英文摘要：

A rapid virtual tree pruning method based on color encoding is proposed to address the challenge of interactive pruning operations in 3D space. The requirements and difficulties are analyzed. Based on ParaTree - a parameter-based 3D tree modeling system, a rapid 3D primitive picking method for a large collection of metadata is proposed. It encodes a 3D tree model with 32-bits RGBA colors, and fulfills interactive stem pruning by leveraging the off-screen buffers of GPU and the color encoding. Experimental results showed that our method is accurate, fast, general-purposed, and is compatible with various tree modeling approaches. The proposed method provides a new way to digital type design and pruning for virtual tree planting and management.