From:
owner-xsi(at)Softimage.COM [mailto:owner-xsi(at)Softimage.COM] On Behalf Of Luc-Eric
Rousseau
Sent: Wednesday, June 06, 2007 3:31 PM
To: XSI(at)Softimage.COM
Subject: RE: [SDK]Double to long in c++ ?
I don't really know the answer to your question, so I appologize if
this is wrong, but the cast operator has higher precedence than the multiply.
so it's going to take that 't', cast it to a long, and do the rest in longs.
I think you wanted to have another set of parenthesis like
(long)(t*3*nbPoints)
in any case,
casting a double to long just like that is not a good idea, you
should add an epsilon to compensate for any numerical innacuracies.
For example : long id = (long)(t*3*nbPoints +
0.25);
From: owner-xsi(at)Softimage.COM
[mailto:owner-xsi(at)Softimage.COM] On Behalf Of Ahmidou Lyazidi
Posted At: Wednesday, June 06, 2007 3:20 PM
Posted To: xsi
Conversation: [SDK]Double to long in c++ ?
Subject: [SDK]Double to long in c++ ?
Hi
In an Operator,we are trying to convert the datas passed by
OperatorContex.GetTime to a long.The thing that is strange is when I log the
value
it seems good, but when I mutiply it with a fixed value it seems to round it
and give me 2 equal values for 2 differant frame
here is the code and the log:
long oOffset = oOp.GetParameterValue(L"TimeOffset");
CTime T = ctxt.GetTime();
Application().LogMessage(L"Current operator Time " + T.GetAsText());
double t = double(T) + oOffset;
long id = (long) t * 3 * nbPoints;
Application().LogMessage( (CString)t +L"* 3 * "+(CString) nbPoints
+L" = "+(CString)id);
if(t>=startFrame && t<=endFrame)
{
Application().LogMessage(L"Reading Frame "+
(CString) t);
for(long a=0;a<nbPoints;a++)
{
inPos[a].Set(position[id],position[id+1],position[id+2]);
id += 3;
}
}
//-----------------------------------------
1* 3 * 4 = 11
NextFrame();
// INFO : Current operator Time 00:00:00:02
// INFO : 2* 3 * 4 = 23
// INFO : Reading Frame 2
NextFrame();
// INFO : Current operator Time 00:00:00:03
// INFO : 3* 3 * 4 = 36
// INFO : Reading Frame 3
NextFrame();
NextFrame();
// INFO : Current operator Time 00:00:00:05
// INFO : 5* 3 * 4 = 60
// INFO : Reading Frame 5
Any ideas?
Thanks
A.
