Just a small clarification. The default value for VTK_USE_64BIT_IDS depends on the type of binary you are building. For 32-bit binaries, it is OFF, for 64-bit binaries it is ON by default.<br><br><div>from VTK's CMakeLists.txt:</div>
<div>=================================<br><div><div>IF("${CMAKE_SIZEOF_VOID_P}" GREATER 4)</div><div> SET(VTK_USE_64BIT_IDS_DEFAULT ON)</div><div>ELSE("${CMAKE_SIZEOF_VOID_P}" GREATER 4)</div><div> SET(VTK_USE_64BIT_IDS_DEFAULT OFF)</div>
<div>ENDIF("${CMAKE_SIZEOF_VOID_P}" GREATER 4)</div><div><br></div><div><br></div><div class="gmail_quote">On Tue, Feb 17, 2009 at 9:10 AM, Berk Geveci <span dir="ltr"><<a href="mailto:berk.geveci@kitware.com">berk.geveci@kitware.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div class="Ih2E3d">> Thorough testing of your extremely large data sets is well warranted. I'm<br>
> not trying to take anything away from VTK. I think it is a wonderful toolkit<br>
> that has allowed me to help people solve real problems. Just a word of<br>
> caution that if your data sets start getting large (into 64 bit territory)<br>
> be ready to possibly hunt down some bugs in the VTK code.<br>
<br>
</div>I would strongly encourage developers and users to report any issues<br>
they find related to 64 bit issues when processing large datasets. We<br>
are actively hunting such bugs. I want to clarify a few things:<br>
<br>
* You will be in the "64 bit territory" when the number of points or<br>
cells in your datasets is bigger than 2^31 (we use signed ints). It is<br>
totally possible to have datasets much larger than 4 GiB without<br>
exceeding 2^31 points/cells.<br>
<br>
* Make sure to turn on VTK_USE_64BIT_IDS before compiling. This is OFF<br>
by default. Without setting VTK_USE_64BIT_IDS to on, you cannot<br>
process datasets that have more than 2^31 points/cells even on a 64<br>
bit machine. When VTK_USE_64BIT_IDS is on, VTK will use a 64 bit<br>
integer for indexing. Otherwise, it will use a 32 bit integer.<br>
<font color="#888888"><br>
-berk<br>
</font><div><div></div><div class="Wj3C7c"><br>
<br>
On Sat, Feb 14, 2009 at 11:16 PM, Michael Jackson<br>
<<a href="mailto:mike.jackson@bluequartz.net">mike.jackson@bluequartz.net</a>> wrote:<br>
> There are those issues and possible issues with 32 bit math results being<br>
> placed into a 64 bit value such as the following:<br>
><br>
> int x, y, z;<br>
><br>
> int64 total = x * y * z;<br>
><br>
> on the surface that looks fine, but what happens when x * y * z goes beyond<br>
> the max signed int value? It rolls over and you get all sorts of weird<br>
> errors.<br>
><br>
> I found and fixed a few of these last year and others have gone on the "64<br>
> bit hunt" before but no one really sure just where the rest of the bugs are<br>
> at.<br>
><br>
> Thorough testing of your extremely large data sets is well warranted. I'm<br>
> not trying to take anything away from VTK. I think it is a wonderful toolkit<br>
> that has allowed me to help people solve real problems. Just a word of<br>
> caution that if your data sets start getting large (into 64 bit territory)<br>
> be ready to possibly hunt down some bugs in the VTK code.<br>
><br>
> ---<br>
> Mike Jackson <a href="http://www.bluequartz.net" target="_blank">www.bluequartz.net</a><br>
><br>
><br>
><br>
> On Feb 14, 2009, at 8:37 PM, shekharc wrote:<br>
><br>
>> No, not atm. Perhaps that's why it works for me so far.<br>
>><br>
>> Is it fair to say that 64-bit issues would crop up when say the array<br>
>> lengths are like 2^32 or bigger (because of ints)? Other libraries (like<br>
>> Blitz++) tend to have this issue too I believe.<br>
>><br>
>> Cheers<br>
>> Shakes<br>
>><br>
>> Sean McBride wrote:<br>
>>><br>
>>> On 2/13/09 12:58 PM, shekharc said:<br>
>>>><br>
>>>> Works fine on Windows Vista/XP x64 and Linux x64 fine for me so far.<br>
>>><br>
>>> Out of curiosity, are you using datasets > 4 GiB?<br>
><br>
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