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Moves IsPointInPolygon to lazregions

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git-svn-id: trunk@33851 -
This commit is contained in:
sekelsenmat 2011-11-29 11:59:02 +00:00
parent 2458c71cfd
commit b267352d83
2 changed files with 52 additions and 52 deletions
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52
lcl/lazcanvas.pas
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@ -78,7 +78,6 @@ type
protected
procedure SetColor (x,y:integer; const AValue:TFPColor); override;
// Routines broken in FPC
function IsPointInPolygon(AX, AY: Integer; const APolygon: array of TPoint): Boolean;
procedure DoPolygonFill (const points:array of TPoint); override;
public
constructor create (AnImage : TFPCustomImage);
@ -169,57 +168,6 @@ begin
Clipping := OldClipping;
end;
// The function will return True if the point x,y is inside the polygon, or
// False if it is not.
//
// Original C code: http://www.visibone.com/inpoly/inpoly.c.txt
//
// Translation from C by Felipe Monteiro de Carvalho
//
// License: Public Domain
function TLazCanvas.IsPointInPolygon(AX, AY: Integer; const APolygon: array of TPoint): Boolean;
var
xnew, ynew: Cardinal;
xold,yold: Cardinal;
x1,y1: Cardinal;
x2,y2: Cardinal;
i, npoints: Integer;
inside: Integer = 0;
begin
Result := False;
npoints := Length(APolygon);
if (npoints < 3) then Exit;
xold := APolygon[npoints-1].X;
yold := APolygon[npoints-1].Y;
for i := 0 to npoints - 1 do
begin
xnew := APolygon[i].X;
ynew := APolygon[i].Y;
if (xnew > xold) then
begin
x1:=xold;
x2:=xnew;
y1:=yold;
y2:=ynew;
end
else
begin
x1:=xnew;
x2:=xold;
y1:=ynew;
y2:=yold;
end;
if (((xnew < AX) = (AX <= xold)) // edge "open" at left end
and ((AY-y1)*(x2-x1) < (y2-y1)*(AX-x1))) then
begin
inside := not inside;
end;
xold:=xnew;
yold:=ynew;
end;
Result := inside <> 0;
end;
procedure TLazCanvas.DoPolygonFill(const points: array of TPoint);
var
lBoundingBox: TRect;

52
lcl/lazregions.pas
View File

@ -61,9 +61,61 @@ type
function IsPointInRegion(AX, AY: Integer): TLazRegionWithChilds; virtual;
end;
function IsPointInPolygon(AX, AY: Integer; const APolygon: array of TPoint): Boolean;
implementation
// The function will return True if the point x,y is inside the polygon, or
// False if it is not.
//
// Original C code: http://www.visibone.com/inpoly/inpoly.c.txt
//
// Translation from C by Felipe Monteiro de Carvalho
//
// License: Public Domain
function IsPointInPolygon(AX, AY: Integer; const APolygon: array of TPoint): Boolean;
var
xnew, ynew: Cardinal;
xold,yold: Cardinal;
x1,y1: Cardinal;
x2,y2: Cardinal;
i, npoints: Integer;
inside: Integer = 0;
begin
Result := False;
npoints := Length(APolygon);
if (npoints < 3) then Exit;
xold := APolygon[npoints-1].X;
yold := APolygon[npoints-1].Y;
for i := 0 to npoints - 1 do
begin
xnew := APolygon[i].X;
ynew := APolygon[i].Y;
if (xnew > xold) then
begin
x1:=xold;
x2:=xnew;
y1:=yold;
y2:=ynew;
end
else
begin
x1:=xnew;
x2:=xold;
y1:=ynew;
y2:=yold;
end;
if (((xnew < AX) = (AX <= xold)) // edge "open" at left end
and ((AY-y1)*(x2-x1) < (y2-y1)*(AX-x1))) then
begin
inside := not inside;
end;
xold:=xnew;
yold:=ynew;
end;
Result := inside <> 0;
end;
{ TLazRegionPart }
function TLazRegionPart.IsPointInPart(AX, AY: Integer): Boolean;