“Frustum-Traced Irregular Z-Buffers: Fast, Sub-pixel Accurate Hard Shadows”

  • ©Chris Wyman, Rama C. Hoetzlein, and Aaron E. Lefohn



Entry Number: 71


    Frustum-Traced Irregular Z-Buffers: Fast, Sub-pixel Accurate Hard Shadows



    We present a system to render real-time, antialised hard shadows using irregular z-buffers. We achieve 32 sample, subpixel accuracy at roughly twice the cost of a single visibility sample. Our system remains interactive on complex CAD models and modern game assets while running at 1080p and above, yet imposes no constraints on light, camera, or geometry allowing fully dynamic scenes without precomputation. We introduce no spatial or temporal aliasing, smoothly animating even subpixel shadows from grass or wires.


    Johnson, G. S., Lee, J., Burns, C. A., and Mark, W. R. 2005. The irregular z-buffer: Hardware acceleration for irregular data structures. ACM Trans. Graph. 24, 4 (Oct.), 1462–1482.
    Wyman, C., Hoetzlein, R., and Lefohn, A. 2015. Frustum-traced raster shadows: Revisiting irregular z-buffers. In Symp. Interactive 3D Graphics and Games, 15–23.


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