When the camera moves away, the shadows gradually fade, but they reappear when the camera gets closer. Is there any way to keep the shadows present at all times? Or can I set a distance at which they will disappear?
for directional light, it has a shadow distance parameter that controls this. The larger the value, the more pixelated the shadow as it needs to stretch over a larger distance.
Shadow cascades help with this, which is useful for larger scenes.