Deep Opacity Maps

We present a new method for computing shadows from semitransparent objects like hair. Extending the concept of opacity shadow maps, the deep opacity map method uses a depth map to obtain a per pixel distribution of opacity layers. This approach totally eliminates the layering artifacts of opacity shadow maps and requires much fewer layers to achieve high quality shadow computation. We provide qualitative comparisons to opacity shadow maps and give performance results. Our algorithm is easy to implement, fast, and memory efficient, enabling us to generate high quality hair self-shadows in real-time using consumer graphics hardware on a standard PC.