I have this big tomographic data interpretation and visualization program on my hands for maintenance. It was started back in 2002 by another developer using Delphi7 and the main development was done up until 2009 using D7, BDS2006 and RAD2007 by the same guy, who then left.
Later on when I took over maintenance I unicodified it and updated the GUI using Delphi XE5 back in 2014-15. I also had to patch the GLScene code to make it work, not much but essential.

Now in view of the way Embarcadero is licensing the development system I am thinking about moving over to FPC/Lazarus instead. New functions have been called for and the original developer is able to consult.

So I am looking for advice on what to think about when doing this migration to FPC.
The project uses an older version of GLScene, which cannot be replaced by any current version because of the way GLScene obsoleted methods and properties in the older versions such that I never could make it work back in 2014, hence the unicode patch of the older version. Apart from this it only uses standard functions in Delphi as far as I know. Plus our own components, which we have full control over...

Suggestions, links etc appreciated!

Bo Berglund wrote

Suggestions, links etc appreciated!

I found this when searching but it is dated back in 2007 so it does not cover how to deal with the string to unicode string change in Delphi 2009 and forward....

https://www.freepascal.org/~michael/articles/lazport2/lazport2.pdf

Bo Berglund wrote

I found this when searching but it is dated back in 2007 so it does not cover how to deal with the string to unicode string change in Delphi 2009 and forward....

Which might be a major issue as Delphi uses UTF-16, While Lazarus uses UTF-8.

-Michael

Yours is a very interesting problem (so please keep the list updated on it if you can), but one that Lazarus and FPC are a very good fit for. Most of the functionality that is hard to duplicate is found in the newer versions of Delphi, such as libraries that rely on anonymous functions and so on.

Have you attempted to port the code? People will probably be able to help better if they are aware of specific problems you are having.

Can you explain the functionality now missing from GLScene that can't be added back? You may need to maintain your own patches to that component, but I fail to see how it would be impossible to bring forward. This isn't to say bringing it forward will be trivial, but even if it is not, getting your codebase compatible with Lazarus/FPC is likely a good longer term goal.

Cheers,
R0b0t1

R0b0t1 wrote

Can you explain the functionality now missing from GLScene that can't be added back?

If I remembered correctly I tried to use GLScene 1.0.something instead of the older version 0.8.2 and the showstopper was that the Canvas property had been removed in the 1.x version and this was heavily used throughout the code.
Since I was just porting the code without understanding the inner workings I could not work around it so I returned to 0.8.2 and patched this for the unicode changes.

The software I am looking at consists of 3 seprate projects for 1D, 2D and 3D processing.
I think I will change foot here and look at the 1D first since this is a pure Delphi native application. Uses Delphi's own graphics.

2D uses GLScene for graphics and 3D is mainly a C++Builder project with some parts implmented using Delphi and the graphics via VTK (which no longer supports Borland compilers).
I think 3D is out for FPC...

Bo Berglund wrote

I think I will change foot here and look at the 1D first since this is a pure Delphi native application. Uses Delphi's own graphics.

Forgot to ask if Lazarus is able to read the dproj project file used by Delphi XE5?

Better ask such question on the Lazarus list or forum.

Mattias

Mattias Gaertner wrote

Better ask such question on the Lazarus list or forum

Sorry, I was using my newsreader in GMane and did not notice I was in the wrong NG...