Procedural world generation - ground and traps seems to not generating.

[User137]

Can you point me to such algorithm?

This should do the thing:

function Random2(const seed, offset: cardinal): double; overload;
var oldSeed: cardinal;
begin
  oldSeed:=randseed; // Save old seed
  randseed:=seed+offset; // Shouldn't need to check high(cardinal) ranges.
  // Overflowing should still do the math perfectly.
  result:=random();
  randseed:=oldSeed; // Restore it afterwards,
  // So that use of normal Random() outside of this function is not interrupted.
end;

function Random2(const n: cardinal; const seed, offset: cardinal): cardinal; overload;
begin
  result:=trunc(Random2(seed, offset)*n);
end;

Edited second Random2() result type.