Makes IntersectRect more robust. See bug #17722

git-svn-id: trunk@16224 -
This commit is contained in:
sekelsenmat 2010-10-26 14:49:35 +00:00
parent 4579226771
commit b4b9354468

View File

@ -344,25 +344,30 @@ end;
function IntersectRect(var Rect : TRect;const R1,R2 : TRect) : Boolean;
var
lR1, lR2: TRect;
begin
Rect:=R1;
with R2 do
begin
if Left>R1.Left then
Rect.Left:=Left;
if Top>R1.Top then
Rect.Top:=Top;
if Right<R1.Right then
Rect.Right:=Right;
if Bottom<R1.Bottom then
Rect.Bottom:=Bottom;
end;
// We copy the parameter to a local variables to avoid problems
// when passing the same rectangle in the var and const parameters.
// See http://bugs.freepascal.org/view.php?id=17722
lR1 := R1;
lR2 := R2;
Rect := lR1;
if lR2.Left > lR1.Left then
Rect.Left := lR2.Left;
if lR2.Top > R1.Top then
Rect.Top := lR2.Top;
if lR2.Right < R1.Right then
Rect.Right := lR2.Right;
if lR2.Bottom < R1.Bottom then
Rect.Bottom := lR2.Bottom;
if IsRectEmpty(Rect) then
begin
begin
FillChar(Rect,SizeOf(Rect),0);
IntersectRect:=false;
end
end
else
IntersectRect:=true;
end;