Real-Time Meshlet Extraction from Scalar Volumes

In this paper, we propose the first approach for real-time extraction and rendering of isosurfaces from scalar volumes as non-trivial persistent meshlets, which are compatible with efficient mesh shader pipelines supported by recent GPUs. Whereas trivial approaches extract from small voxel blocks to ensure that meshlets adhere to geometry size limits, our method partitions and extracts from larger blocks, increasing the number of primitives per meshlet for improved rendering efficiency. Our isosurface extraction method performs fine-grained region analysis and adaptive partitioning of occupied blocks in a task shader stage, followed by efficient meshlet extraction in a mesh shader stage. The region analysis kernel provides the meshlet extraction kernel with compact occupancy information that allows computational resources to be focused on cells that contribute to the isosurface. An extensive analysis reveals that, compared to the state-of-the-art technique, our approach significantly improves extraction and rendering performance  and reduces the memory footprint of extracted isosurfaces in most cases.