Real-time rendering of pixel-accurate hard shadows in 3D scenes is still a challenging problem for shadow generation techniques. In this paper, we present the concept of non-overlapping geometric shadow map (NOGSM), which enables the construction of high-quality hard shadows from static lights for any point in the scene. The NOGSM is created in a preprocessing phase, in which the scene’s geometry is looked at from the light’s point of view. All hidden surfaces are removed through total elimination of hidden polygons plus clipping of the partially hidden polygons. The resulting list of non-overlapping projected polygons is then stored in a multi-grid data structure. Our solution generates shadows with far better quality than standard shadow mapping techniques, while maintaining real time performance, and using a smaller memory footprint than compression techniques.

在 3D 场景中实时渲染像素精确的硬阴影仍然是阴影生成技术的一个具有挑战性的问题。在本文中，我们提出了非重叠几何阴影贴图 (NOGSM) 的概念，它能够为场景中的任何点从静态光构建高质量的硬阴影。NOGSM 是在预处理阶段创建的，其中从灯光的角度查看场景的几何形状。通过完全消除隐藏多边形加上裁剪部分隐藏的多边形来移除所有隐藏的表面。然后将生成的非重叠投影多边形列表存储在多网格数据结构中。我们的解决方案生成的阴影质量远高于标准阴影映射技术，同时保持实时性能，