I'd just c_trace for the first hit, then use the resulting hit distance as the factor for the mouse pos calculation:

hitDistance = c_trace... // calculate once on first click
...
vec_set(temp,mouse_dir3d); // dir, not pos!
vec_scale(temp,hitDistance);
vec_add(temp,camera.x);
=> move to temp

"Falls das Resultat nicht einfach nur dermassen gut aussieht, sollten Sie nochmal von vorn anfangen..." - Manual

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