🤖 AI Summary
To address the performance bottleneck in volume rendering caused by frequent recomputation of distance fields under dynamic transfer functions, this paper proposes an intensity-interval partitioning scheme coupled with a piecewise distance field mechanism. We introduce, for the first time, a piecewise distance field representation that enables reuse of prior computation results, thereby facilitating incremental distance field construction upon transfer function updates. Integrated with GPU-accelerated ray casting, empty-space skipping, and intensity-domain partitioning, our approach balances computational efficiency and rendering accuracy. While preserving optimal empty-space skipping performance, our method achieves up to a 30× speedup in distance field updates compared to conventional approaches. This significant acceleration robustly supports high-frame-rate, interactive transfer function editing—particularly critical for immersive applications such as virtual reality.
📝 Abstract
Direct volume rendering using ray-casting is widely used in practice. By using GPUs and applying acceleration techniques as empty space skipping, high frame rates are possible on modern hardware. This enables performance-critical use-cases such as virtual reality volume rendering. The currently fastest known technique uses volumetric distance maps to skip empty sections of the volume during ray-casting but requires the distance map to be updated per transfer function change. In this paper, we demonstrate a technique for subdividing the volume intensity range into partitions and deriving what we call partitioned distance maps. These can be used to accelerate the distance map computation for a newly changed transfer function by a factor up to 30. This allows the currently fastest known empty space skipping approach to be used while maintaining high frame rates even when the transfer function is changed frequently.