[vtkusers] Forward Declarations in 4.x

[Chris Scharver]

Hello,

I decided to get daring and move beyond Makefiles to creating a new executable with Project Builder on MacOS X. I got a pretty surprising mess. There were a lot of errors about forward declarations and being unable to match function calls. I'm using the cvs snapshot, but the code compiled fine under Win32 with VTK 4.0. VTK itself built fine, and so did the tests.

I was able to eventually work around all the errors by explicitly including some additional VTK headers. Is this a VTK 4.n change resulting from the use of forward declarations? If so, it may be a good item to add to 6.8 "Changes to VTK since 4.0" on the FAQ. At first I thought I was just having some Mac issue. I was caught off-guard, but the benefits of using forward declarations are worth it!

Chris
--
Chris Scharver
Electronic Visualization Laboratory
The University of Illinois at Chicago
Ph: 312-996-3002   FAX: 312-413-7585
<http://www.evl.uic.edu/scharver/>