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Finds where LineA and LineB intersect. I'm keeping them as TBoxs since there isn't anything called TLine… at least not that I know of. Maybe TPoints would be better but this served it purpose so I thought I'd share it with the community.

program New;
var
  Pt: TPoint;

function Intersect(LineA, LineB: TBox): TPoint;
var
  A, B, C: array [0..1] of Integer;
  Det: Integer;
begin
  A[0]:= LineA.y2 - LineA.y1;
  B[0]:= LineA.x1 - LineA.x2;
  C[0]:= (A[0] * LineA.x1) + (B[0] * LineA.y1);
  
  A[1]:= LineB.y2 - LineB.y1;
  B[1]:= LineB.x1 - LineB.x2;
  C[1]:= (A[1] * LineB.x1) + (B[1] * LineB.y1);
  
  Det:= (A[0] * B[1]) - (A[1] * B[0]);
  if(Det <> 0)then
    begin
      Result.x:= ((B[1] * C[0]) - (B[0] * C[1])) div Det;
      Result.y:= ((A[0] * C[1]) - (A[1] * C[0])) div Det;
    end else
      begin
        Result.x:= -1;
        Result.y:= -1;
      end;
end;


begin
Pt:= Intersect(IntToBox(0, 0, 4, 4), IntToBox(4, 0, 0, 4));
Writeln('x:= ' + inttostr(Pt.x));
Writeln('y:= ' + inttostr(Pt.y));
end.

From: Special Ed
Finds where LineA and LineB intersect. I'm keeping them as TBoxs since there isn't anything called TLine… at least not that I know of. Maybe TPoints would be better but this served it purpose so I thought I'd share it with the community.

program New;
var
  Pt: TPoint;

function Intersect(LineA, LineB: TBox): TPoint;
var
  A, B, C: array [0..1] of Integer;
  Det: Integer;
begin
  A[0]:= LineA.y2 - LineA.y1;
  B[0]:= LineA.x1 - LineA.x2;
  C[0]:= (A[0] * LineA.x1) + (B[0] * LineA.y1);
  
  A[1]:= LineB.y2 - LineB.y1;
  B[1]:= LineB.x1 - LineB.x2;
  C[1]:= (A[1] * LineB.x1) + (B[1] * LineB.y1);
  
  Det:= (A[0] * B[1]) - (A[1] * B[0]);
  if(Det <> 0)then
    begin
      Result.x:= ((B[1] * C[0]) - (B[0] * C[1])) div Det;
      Result.y:= ((A[0] * C[1]) - (A[1] * C[0])) div Det;
    end else
      begin
        Result.x:= -1;
        Result.y:= -1;
      end;
end;


begin
Pt:= Intersect(IntToBox(0, 0, 4, 4), IntToBox(4, 0, 0, 4));
Writeln('x:= ' + inttostr(Pt.x));
Writeln('y:= ' + inttostr(Pt.y));
end.

Wow, never thought of that idea

Did the site I post help?

From: Bobarkinator
Did the site I post help?

Yes, Yes it did… except they did it in C++ and had some stuff missing out. I had an idea of how to do it but this just helped me execute it.

Ah, just wondering. Looks like you did a find job though.

From: Bobarkinator
Ah, just wondering. Looks like you did a find job though.

Thank you! I wonder if anyone other than me and bullzeye will actually use it though?

From: Special Ed
Thank you! I wonder if anyone other than me and bullzeye will actually use it though?

It's always good to have lying around ;)

what were you thinking of using it for when you made it? :p just cuious.

~RM

what does it do? :(

I feel left behind

From: Zytex!
what does it do? :(

I feel left behind

Finds the point where 2 lines intersect.

*dictionary-time* Aha! thanks

kinda cool… :P

why do I think this is for msi…

From: Mylesmadness
why do I think this is for msi…

Because I'm to un-motivated (Better word for lazy) to do any work that isn't for MSI right now :p

@Rasta - Me and bullzeye are using it for a walking system he thought of. This is needed to find the center of the road.

No difference but the name'll just suit better -

Type
  TLine = Record
    x1, y1, x2, y2: Integer;
  end;

Here's the one i made for my 3DModel drawer thingy-

function Intersection(x1, y1, x2, y2, x3, y3, x4, y4: integer): TPoint;
var
  Denom: integer;
begin
  Denom:= ((y2 - y1) * (x3 - x4) - (y4 - y3) * (x1 - x2));
  if Denom = 0 then
  begin
    Result.x:= 0;
    Result.y:= 0;
    Exit;
  end;
  Result.x:=((x1 - x2) * (x4 * y3 - x3 * y4) - (x3 - x4) * (x2 * y1 - x1 * y2)) / Denom;
  Result.y:=((y4 - y3) * (x2 * y1 - x1 * y2) - (y2 - y1) * (x4 * y3 - x3 * y4)) / Denom;
end;

Heh… nice almost. That's literally the exact same thing just without the in-betweens I had.

Oh well, I'll use your instead if you don't mind :p

Yup that's fine

I could of used this in my Maths Methods SAC today :) apart from the fact i can do it by hand, lol