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this such as perspective shadow mapping.
Illustration 2: Shadow Mapping Pipeline
References:
Williams, L. 1978. Casting Curved Shadows on Curved Surfaces. In Computer
Graphics (Proceedings of SIGGRAPH 1978), Vol. 12, 39–42.
http://www.paulsprojects.net/tutorials/smt/smt.html
5.2.2
Variance Shadow Mapping (VSM)
An improvement to the shadow mapping algorithm where a second depth buffer is used to
store additional data which can be used to more accurately filter the projected shadow:
reducing the amount of aliasing.
References:
Donnelly, W. 2002. Variance Shadow Maps. In Computer Graphics (Proceedings of
I3D 2006), 161–165
5.2.3
Shadow Volumes (Stencil Shadows)
This technique is more computationally expensive because of the calculation of the shadow
volume however this should be lessened by the simplicity of the geometry in the game. This
technique yields more crisp shadows than either VSM or Shadow Mapping. Shadow
volumes are the most optimal technique as it allow for clean shadows that can be
implemented in the RSX chip.
References:
Carmack, J. 2000. Carmack on Shadow Volumes. Personal correspondence between
Mark Kilgard and John Carmack.
Crow, F. C. 1977. Shadow Algorithms for Computer Graphics. In Computer Graphics
(Proceedings of SIGGRAPH 77), Vol. 11, 242–248.