Matěj Sakmary
Supervisor(s): Jiří Bittner
Czech Technical University
Abstract: In this article, we present Resolution Matched Virtual Shadow Maps (RMVSMs), a method of rendering shadow maps with greatly improved quality and memory efficiency compared to traditional methods. We separate logical address space from its physical backing by splitting each shadow map cascade into a set of virtual pages. This achieves the appearance of a large contiguous memory without the need to reserve backing physical memory. For each frame, we find the set of visible pages by analyzing the depth buffer. Each visible page is assigned physical memory allocated from a designated memory pool. To efficiently fill visible pages with shadow map information, we utilize granular culling of the scene geometry. We show that our implementation is well suited for multiple light sources of various types, including directional lights, point lights, and spotlights. Further, we show that this technique scales to an arbitrary number of cascades as only a fraction of virtual pages are visible and need to be backed each frame. We can thus achieve any desired texel-to-pixel density at any distance with few wasted shadow texels.
Keywords: Geometry Processing, Graphics Hardware, Real-time Graphics, Rendering
Full text: Year: 2025
