Cascaded shadow mapping tutorial has disappearing shadows

[enginmanap]

In the following part of the example:

LearnOpenGL/src/8.guest/2021/2.csm/shadow_mapping.cpp

Line 703 in a545a70

constexpr float zMult = 10.0f;

MinZ/MaxZ is calculated based on the player perspective, but if the resulting min/max is between -1 and 0, then the operation makes the orthogonal matrix smaller than player visible area, resulting in missing shadows, only on specific view angles + positions, as resulting frustum corner has to be (-1,0).