Before setting up shadows, this page will explain why ASP uses at least one additional shadow map or the new proxy cube to remove self shadowing.
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Starting from ASP v1.3, we introduced a new option that removes self-shadowing using a proxy cube culling method. Compared to rendering an extra character-only shadow map, this method is easier to set up and offers better performance. In the sections below, the setup steps for both approaches are listed separately. Please choose only one method for your project. Do not enable both.
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In general, when using the built-in shadow map, the self-shadowing effect on the character is not ideal. This is because the size of the shadow map is limited - the same shadow map must be able to contain the entire scene, and the characters in the scene usually only occupy a very small part of the shadow map (even with Unity's built-in 4-layer Cascaded Shadow Map, it is still not enough).
In the image above, the shadows cast by the hair and face mesh will produce undesirable self-shadowing on themselves because the shadow map is not large enough.
Simply changing the ShadowCaster of the hair and face mesh to Off can avoid the self-shadowing from the face and hair, but the character's shadow on the ground will also be missing the face and hair.
How it works :
In the character shadow algorithm used in Gravity Rush (PS Vita version), the character does not sample the shadow map using the current pixel’s world-space position.
Instead, the system wraps the character with a virtual proxy cube that fully contains the entire model.
During rendering, the character shader traces outward from the surface of this cube toward the light direction, finds the first intersection point between the cube surface and the light source, and uses only that hit point to sample the shadow map.
With this setup:
✔ The character produces no self-shadow at all
Because the sampling position always comes from the cube’s outer surface, none of the character’s internal surfaces participate in self-shadowing.