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Well... I think BCB6 will survive for a long time because the new
BuilderX is a completely different product and it is not mature yet.<br>
And probably it will be not for a long time: there are rumors that
Borland will change again the BuilderX platform to include wxwindows (
<a class="moz-txt-link-freetext" href="http://www.wxwindows.org">http://www.wxwindows.org</a> ) libraries.<br>
So stay tuned and help all of us that use BCB all day long to fix and
upgrade it more because it is powerful but not perfect, yet!<br>
I hope to have time asap to fix the "ProjectDemo" myself but I am new
to VTK and I do not know how to do it yet.<br>
Right now the problem disappear even if you compile your project and
package using runtime dll (Options->Linker->Use dynamic RTL).<br>
Is it a real problem to include borland dlls till this problem is
solved?<br>
<br>
Luca<br>
<br>
PS: if you believe microsoft .net will be the future... well.. it is a
completely different product from previous visual studio and it is at
the same point of builderx.<br>
Use both of them at your risk :-)<br>
Take care<br>
<br>
<br>
<br>
John Biddiscombe wrote:
<blockquote cite="mid000c01c406ab$b504a010$2901460a@miradasolutions.com"
type="cite">
<pre wrap="">VTK\Examples\GUI\Win32\vtkBorland\ProjectDemo
it's the original Borland demo, which has never been attended to. Please fix
it if you have time. Mind you, now that Borland are dumping BCB, it's worth
discouraging people from adopting it.
JB
----- Original Message -----
From: "William A. Hoffman" <a class="moz-txt-link-rfc2396E" href="mailto:billlist@nycap.rr.com"><billlist@nycap.rr.com></a>
To: "Xianjin Yang" <a class="moz-txt-link-rfc2396E" href="mailto:Yang@AGIUSA.COM"><Yang@AGIUSA.COM></a>; <a class="moz-txt-link-rfc2396E" href="mailto:vtkusers@vtk.org"><vtkusers@vtk.org></a>
Cc: "Per Dalgas Jakobsen" <a class="moz-txt-link-rfc2396E" href="mailto:pdj@maridan.dk"><pdj@maridan.dk></a>
Sent: Wednesday, March 10, 2004 2:13 PM
Subject: RE: [vtkusers] Serious(?) flaws in vtk code
</pre>
<blockquote type="cite">
<pre wrap="">Where is Project_vtkDemo? Can it be fixed so other people
do not run into this problem?
-Bill
At 12:32 PM 3/9/2004, Xianjin Yang wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Dear all,
I have been using BCB6 + VTK 4.2 and had similar problems before.
To solve Access violation problem related to DummyCritSect.Lock() in the
</pre>
</blockquote>
</blockquote>
<pre wrap=""><!---->destructor of vtkPolyData (~vtkPolyData), I did these in the
Project_vtkDemo:
</pre>
<blockquote type="cite">
<blockquote type="cite">
<pre wrap="">1) Remove everything in the FormDestroy event handler.
2) Add this FormClose event handler. All problems should be gone!!
void __fastcall TVTK_Form::FormClose(TObject *Sender, TCloseAction
</pre>
</blockquote>
</blockquote>
<pre wrap=""><!---->&Action)
</pre>
<blockquote type="cite">
<blockquote type="cite">
<pre wrap="">{
if (shrink) shrink->Delete();
vtkTimerLog::DeallocateTimerLog();
vtkWindow1->GetRenderer()->RemoveAllProps();
// VTK_Form->Release();
// Application->Terminate();
}
I am not sure if the last two lines of code are required in BCB6.
vtkTimerLog::DeallocateTimerLog() is a fix discussed here:
</pre>
</blockquote>
<pre wrap=""><a class="moz-txt-link-rfc2396E" href="http://public.kitware.com/pipermail/vtkusers/2003-August/019522.html"><http://public.kitware.com/pipermail/vtkusers/2003-August/019522.html></a>http:
</pre>
</blockquote>
<pre wrap=""><!---->//public.kitware.com/pipermail/vtkusers/2003-August/019522.html
</pre>
<blockquote type="cite">
<blockquote type="cite">
<pre wrap="">Xianjin Yang, Ph.D.
-----Original Message-----
From: William A. Hoffman
</pre>
</blockquote>
</blockquote>
<pre wrap=""><!---->[<a class="moz-txt-link-rfc2396E" href="mailto:billlist@nycap.rr.com"><mailto:billlist@nycap.rr.com></a><a class="moz-txt-link-freetext" href="mailto:billlist@nycap.rr.com">mailto:billlist@nycap.rr.com</a>]
</pre>
<blockquote type="cite">
<blockquote type="cite">
<pre wrap="">Sent: Tuesday, March 09, 2004 10:18 AM
To: Per Dalgas Jakobsen; <a class="moz-txt-link-abbreviated" href="mailto:vtkusers@vtk.org">vtkusers@vtk.org</a>
Subject: Re: [vtkusers] Serious(?) flaws in vtk code
I have not looked at the BCB Windows code, however,
it seems that you might be able to move the creation/destruction
of the vtk objects to a different spot. There must be some method
that is called to initialize the BCB objects, and another one
to destroy them. You could go to some sort of lazy create if
there is no such method. Basically, the first time the vtk object
is used, then create the vtk object. Then when your window gets the
</pre>
</blockquote>
</blockquote>
<pre wrap=""><!---->close event, destroy the vtk object, don't just create and destroy the vtk
objects in the constructor/destructor of the BCB object. All vtk objects
should be created after main, and deleted before the end of main, and you
should have no problem.
</pre>
<blockquote type="cite">
<blockquote type="cite">
<pre wrap="">-Bill
At 04:19 AM 3/9/2004, Per Dalgas Jakobsen wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Hi all,
I believe I have found some flaws in the vtk code.
I think most vtk users are not affected, but us poor souls that are
forced to use Borland C++ Builder (BCB) are affected.
</pre>
</blockquote>
<blockquote type="cite">
<pre wrap="">The problem reveals itself the following way (in my case at least):
Access violation in the destructor of vtkPolyData (~vtkPolyData) - The
DummyCritSect.Lock() call fails.
The cause is that DummyCritSect, in certain cases, has already been
destroyed. In other words: ~vtkPolyData is calling a method in an
object that is no longer in existence.
Explanation:
DummyCritSect is a "nonlocal" object which is created before main() is
executed, and destroyed after main() has returned. This is actually
what is intended, and quite nice, except when used from within (but not
exclusively) BCB...
The problem is that the Visual Component Library (VCL), which is the
foundation of BCB, also seems to be created from a "nonlocal" object.
This means that BCB Windows and DummyCritSect are created at the same
point, and destroyed at the same point, but the sequence is undefined.
According to "The C++ Programming Language" by Bjarne Stroustrup:
-------
Section 10.4.9 Nonlocal store:
1) "A variable defined outside any function (that is, global,
namespace, and class static variables; §C.9) is initialized
(constructed) before main() is invoked, and any such variable that has
been constructed will have its destructor invoked after exit from
main()."
2) "No implementation-independent guarantees are made about the order
of construction of nonlocal objects in different compilation units."
3) "The order of destruction is similarly implementation-dependent."
-------
This means that IF vtk is accessed from a "nonlocal" object, it is
implementation-dependent wether it works or not. In case of BCB, it
doesn't :-(
As long as you are not making components containing vtk-code in BCB, it
is possible to make workarounds, but it seems to be impossible to get
component-wrapped vtk-code to work correctly.
How do we get around this problem?
I don't think that we should "#ifdef __BORLANDC__" our way out of the
BCB problem, this will leave the code flawed for projects using
nonlocal objects. Any thoughts?
Best regards
Per
</pre>
</blockquote>
</blockquote>
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</pre>
<blockquote type="cite">
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