Atlas packing is a key step in many computer graphics applications. Packing algorithms seek to arrange a set of charts within a fixed-size atlas with as little downscaling as possible. Many packing applications such as content creation tools, dynamic atlas generation for video games, and texture space shading require on-the-fly interactive atlas packing. Unfortunately, while many methods have been developed for generating tight high-quality packings, they are designed for offline settings and have running times two or more orders of magnitude greater than what is required for interactive performance. While real-time GPU packing methods exist, they significantly downscale packed charts compared to offline methods. We introduce a GPU packing method that targets interactive speeds, provides packing quality approaching that of offline methods, and supports flexible user control over the tradeoff between performance and quality. We observe that current real-time packing methods leave large gaps between charts and often produce asymmetric, or poorly balanced, packings. These artifacts dramatically degrade packing quality. Our Tight And Balanced method eliminates these artifacts while retaining Interactive performance. TABI generates tight packings by compacting empty space between irregularly shaped charts both horizontally and vertically, using two approximations of chart shape that support efficient parallel processing. We balance packing outputs by automatically adjusting atlas row widths and orientations to accommodate varying chart heights. We show that our method significantly reduces chart downscaling compared to existing interactive methods while remaining orders of magnitude faster than offline alternatives.

翻译：图集打包是众多计算机图形学应用中的关键步骤。打包算法旨在将一组图表尽可能少地进行缩放，并安置在固定尺寸的图集内。许多打包应用，如内容创作工具、视频游戏的动态图集生成以及纹理空间着色，都需要实时交互式图集打包。然而，尽管已有多种方法被开发用于生成紧密的高质量打包方案，但它们均针对离线场景设计，其运行时间比交互性能所需的时间高出两个数量级甚至更多。虽然存在实时GPU打包方法，但与离线方法相比，它们对打包图表的缩放程度显著更大。本文提出一种面向交互速度的GPU打包方法，其打包质量接近离线方法，并支持用户灵活控制性能与质量之间的权衡。我们观察到，当前的实时打包方法在图表之间留下较大空隙，且常产生不对称或平衡性差的打包结果。这些伪影会严重降低打包质量。我们提出的紧密且平衡方法在保持交互性能的同时，消除了这些伪影。TABI通过水平和垂直方向压缩不规则形状图表之间的空白区域来生成紧密的打包方案，该方法使用了两种支持高效并行处理的图表形状近似表示。我们通过自动调整图集行宽和方向以适应不同图表高度，实现了打包输出的平衡。实验表明，与现有交互式方法相比，我们的方法显著减少了图表缩放，同时仍比离线替代方案快数个数量级。