SRL Archive - Suggestions

Atm it's a procedure, but I think it should be a function that returned TPointArray.

I agree, but please read this: http://villavu.com/forum/showthread.php?t=57682

Why? If you want the original points back, you just invert it again. Or make a copy beforehand.

From: Wizzup?
Why? If you want the original points back, you just invert it again. Or make a copy beforehand.

This^ that or just make your own.

function InvertedTPA(TPA: TPointArray): TPointArray;
begin
  Result := TPA;
  InvertTPA(Result);
end;

From: IceFire908
This^ that or just make your own.

function InvertedTPA(TPA: TPointArray): TPointArray;
begin
  Result := TPA;
  InvertTPA(Result);
end;

This does (or should) not work. You need to copy it manually.

From: Wizzup?
Why? If you want the original points back, you just invert it again. Or make a copy beforehand.

Because a function can do the same that the procedure
TPA := InvertTPA(TPA)

but as a procedure if we want to assign the inverted TPA to another variable
TPA2 := TPA;
InvertTPA(TPA2);
It's 2 lines :rolleyes:

TPA2 := InvertTPA(TPA)*

From: Wizzup?
This does (or should) not work. You need to copy it manually.

{.include SRL\SRL.scar}

function InvertedTPA(TPA: TPointArray): TPointArray;
begin
  Result := TPA;
  InvertTPA(Result);
end;

procedure ListTPA(TPA: TPointArray);
var
  I: LongInt;
begin
  for I := 0 to High(TPA) do
    WriteLn(IntToStr(TPA[I].X) + ', ' + IntToStr(TPA[I].Y));
end;

var
 TPA, bTPA: TPointArray;

begin
  TPA := [Point(0, 0), Point(1, 1), Point(2, 2)];
  ListTPA(TPA);
  bTPA := InvertedTPA(TPA);
  ListTPA(bTPA);
end.

Successfully compiled (4621 ms)
0, 0
1, 1
2, 2
2, 2
1, 1
0, 0
Successfully executed

Seems to work fine, why wouldn't it work?

Agreed though, this is trivial.. the current system is fine/better

From: IceFire908

{.include SRL\SRL.scar}

function InvertedTPA(TPA: TPointArray): TPointArray;
begin
  Result := TPA;
  InvertTPA(Result);
end;

procedure ListTPA(TPA: TPointArray);
var
  I: LongInt;
begin
  for I := 0 to High(TPA) do
    WriteLn(IntToStr(TPA[I].X) + ', ' + IntToStr(TPA[I].Y));
end;

var
 TPA, bTPA: TPointArray;

begin
  TPA := [Point(0, 0), Point(1, 1), Point(2, 2)];
  ListTPA(TPA);
  bTPA := InvertedTPA(TPA);
  ListTPA(bTPA);
end.

Successfully compiled (4621 ms)
0, 0
1, 1
2, 2
2, 2
1, 1
0, 0
Successfully executed

Seems to work fine, why wouldn't it work?

Agreed though, this is trivial.. the current system is fine/better

It shouldn't work as Arrays are technically Pointers, so you reference the same memory. But perhaps PascalScript does not do this. (It really should)

also @ marpis: Why don't you read what I posted in here before… It explains the difference and why it is there.

From: Wizzup?
It shouldn't work as Arrays are technically Pointers, so you reference the same memory. But perhaps PascalScript does not do this. (It really should)

Ah, we'll it's not the first rule we've broken. =P

From: Wizzup?
It shouldn't work as Arrays are technically Pointers, so you reference the same memory. But perhaps PascalScript does not do this. (It really should)

And how else would we copy the array into memory?

Anyway, I think adding MirrorTPA / InvertedTPA wouldn't hurt.

(I Prefer mirror as it's a clear distinction)

~RM

From: Rasta Magician
And how else would we copy the array into memory?

~RM

SetArrayLength(TPA2, GetArrayLength(TPA));
H := High(TPA);
for I := 0 to H do
  TPA2[I] := Point(TPA[I].X, TPA[I].Y);

From: Zyt3x

SetArrayLength(TPA2, GetArrayLength(TPA));
H := High(TPA);
for I := 0 to H do
  TPA2[I] := Point(TPA[I].X, TPA[I].Y);

True.

function MirrorTPA(TPA: TPointArray): TPointArray;
var
  i, h: integer;
begin d

  h := 0;
  SetLength(Result, Length(TPA));

  for i := High(TPA) DownTo 0 do
  begin
    Result[h] := TPA[i];
    Inc(h);
  end;

end;

~RM

RM, why the h var? If the lengths are the same, is there a reason you shouldn't do

Result[i] := TPA[i];

?

E: Nevermind. :duh: Didn't consider the downto. -.-