clip_size This variable (default 0.5) gives the minimum number of pixels that must be covered by a z buffer shadow triangle for being rendered. With the default value, triangles are not rendered if they are smaller than half a pixel. This increases the frame rate, but can lead to "holes" in z buffer shadows of high polygon models. When using high polygon models, clip_size should be set to 0.
But you should change this value only if you see holes or other artifacts in the mesh and its shadow at runtime..
