Enhancing shadow maps via screen-space visibility

Real-time rendering often suffers from some kinds of artifacts, such as shadow related issues like Shadow Acne and Peter Panning in Shadow Maps, and limitations in Screen Space Shadows due to data constraints. We analyze these artifacts and introduce a hybrid shadow rendering technique that combines the strengths of Shadow Maps and Screen Space Shadows. By leveraging Shadow Maps for global coverage and Screen Space Shadows for local detail refinement, our method dynamically applies Screen Space Shadows to regions prone to Shadow Acne and Peter Panning, guided by a classification of "safe zone" and "dangerous zone" derived from analyzing traditional Shadow Maps. The results show that our method effectively mitigates common artifacts and provides an efficient solution for generating high-quality shadows, making it particularly suitable for resource-constrained environments.