Bug in MakeCompass.

[mastaraymond]

Well this isn't a question but a bug. You all know the MakeCompass command i guess well there is a small bug in it, which means you always turn the long way instead of the small one. To fix this do the following:

Go to Srl\core\MapWalk.scar

at line 94 and 95 you should see this

if StartPos > EndPos then Left_Right := True
    else if StartPos < EndPos then Left_Right := False

Change it to:

If (LowerCase(Side) = 'n') or (LowerCase(Side) = 's') then
  begin;
    if StartPos > EndPos then Left_Right := False
    else if StartPos < EndPos then Left_Right := True
    else exit;
  end else
  begin;
    if StartPos > EndPos then Left_Right := True
    else if StartPos < EndPos then Left_Right := False
    else exit;
  end;

Now it will always rotate the shortest way .

[rotflmfwao]

Thanks!

[passiondrive]

Nice, not that it makes much of a difference though

[Starblaster100]

Not sure about that, consider these two scenarios:

If our StartPos is 10 degrees and EndPos 330 degrees, then the shortest way will be to rotate leftwards. StartPos < EndPos therefore Left_right will be true.

However, If our StartPos is 350 degrees and EndPos 320 degrees, then the shortest way will be to rotate leftwards. StartPos > EndPos therefore Left_right will be False (This is now not the shortest way to rotate the compass!)

Its not as easy as that

[mastaraymond]

Not sure about that, consider these two scenarios:

If our StartPos is 10 degrees and EndPos 330 degrees, then the shortest way will be to rotate leftwards. StartPos < EndPos therefore Left_right will be true.

However, If our StartPos is 350 degrees and EndPos 320 degrees, then the shortest way will be to rotate leftwards. StartPos > EndPos therefore Left_right will be False (This is now not the shortest way to rotate the compass!)

Its not as easy as that

Yes i know that, i found that problem too. I don't know when i changed this it mostly turns the shortest way. So i consider it as a bug ^^. If you don't, please remove this topic because it doesn't makes sense then. I have got a way to fix this, if you want me to i can do it I think it is because i tested it at makeCompass('n')

[Starblaster100]

There is no need to delete the topic. However, if you want to, I know you have the option to delete your own topic.

It's a good challenge - making a procedure to rotate the compass the shortest distance. It took me a good hour to get my head around the maths

[nielsie95]

How about something like this:

program New;

procedure CompassDir(Start, Angle: Integer);
var
  Left: Boolean;
begin
  if Min(iAbs((Angle - (360 + Start)) mod 360), iAbs((Angle - (180 + Start)) mod 360)) = iAbs((Angle - (360 + Start)) mod 360) then Left := True;
  if Left then WriteLn('Turn Left!') else WriteLn('Turn Right!');
end;

begin
  CompassDir(0, 350);
end.

The actual line you need:

Min(iAbs((Angle - (360 + Start)) mod 360), iAbs((Angle - (180 + Start)) mod 360)) = iAbs((Angle - (360 + Start)) mod 360) then Left := True;

Where Start is the Starting angle and Angle is the EndAngle.

[mastaraymond]

Check first post i found it, it works 100%. Please edit my bug tracker to! I tested it and it works at all angles etc. .
change it to:

If (LowerCase(Side) = 'n') or (LowerCase(Side) = 's') then
  begin;
    if StartPos > EndPos then Left_Right := False
    else if StartPos < EndPos then Left_Right := True
    else exit;
  end else
  begin;
    if StartPos > EndPos then Left_Right := True
    else if StartPos < EndPos then Left_Right := False
    else exit;
  end;

[Venom666]

kool, nice work

[Esteban]

still makes the compass whatever direction the long way.