Celestia Forums

Hi,
I am new to Celestia, and I think it looks very nice. I have installed it on both Linux and Windows, and I have noticed several strange differences between the two versions (both are 1.3.2):

- Movie capturing is only in Windows.
- Render menu on the menu bar only in Windows. Settings in Linux version are found in Options menu.
- Linux version has a tool bar, Windows version does not.

Why those differences? Isn't the same source code compiled for every platform? Also the manual seems to be written for the Windows version, with not much said about the differences. This might bother others more than it bothers me, what about users with Linux only who want to make movies? And what about those poor souls looking for the Render menu without finding it?

I have been using another open source app, Blender 3d, for years, and same version for different platforms are always as identical as possible, so I don't think this should be a very big problem to do something about.

I just wanted to mention it, so Happy New Year to all of you!

Hans Petter

hanspb wrote:- Movie capturing is only in Windows.
- Render menu on the menu bar only in Windows. Settings in Linux version are found in Options menu.
- Linux version has a tool bar, Windows version does not.

Why those differences? Isn't the same source code compiled for every platform?

The engine code is the same but each platform uses a different GUI code. There are even four different interfaces for Linux : GLUT (barebone core, basically only the OpenGL window), GTK, Gnome and KDE.

The reason for this is that there isn't a fully satisfying way to make a cross-platform application which will look and behave like a native application on all platforms. The current situation is a trade off between limiting the amount of code duplication and platform integration.

To answer the points you raise:
- Movie capture: there isn't a "standard" audio/video codec framework for Linux yet. Several are available, each is a moving target with a fast evolving interface and none is readily available from within KDE or Gnome. Using one of them would require a lot of code and either require insane dependencies or integrating a snapshot inside the Celestia CVS. We can expect that, in the coming months, dust will settle in this area and that a standard media framework will emerge with appropriate bindings for the various desktops.

- Menu layout: these differencies mainly stem from the different UI design guidelines. e.g. Windows uses "Favorites" while KDE uses "Bookmarks".

- Toolbar: This is a very easy addition to make to a KDE application, it's a more complex task under Windows.

hanspb wrote:Also the manual seems to be written for the Windows version, with not much said about the differences. This might bother others more than it bothers me, what about users with Linux only who want to make movies? And what about those poor souls looking for the Render menu without finding it?

The manual was written by a windows user, so it focuses on the windows version. I made several small additions relating to the KDE version when I converted the original word document to the KDE handbook format, but that was far from comprehensive.

You, as any other motivated Celestia user, are welcome to contribute.

hanspb wrote:I have been using another open source app, Blender 3d, for years, and same version for different platforms are always as identical as possible, so I don't think this should be a very big problem to do something about.

Blender has taken the course opposite to the one chosen by Celestia. They've developped their own cross-platform toolkit, so yes, Blender does look the same on all platforms, but on all platforms it looks different from all other apps.

The Celestia developpers felt it was more important to have Celestia behave like the other app for the vast majority of users who use only one platform, than making the small minority confortable with having the exact same app on all platforms. But as I said, it is a trade off, and it makes some things, like internationalisation and documentation, more difficult.

hanspb wrote:I just wanted to mention it, so Happy New Year to all of you!

My best wishes for the New Year.

Christophe wrote:We can expect that, in the coming months, dust will settle in this area and that a standard media framework will emerge with appropriate bindings for the various desktops.

Maybe this is called gStreamer?
Yes, it's still very alpha....

Thanks for a good answer.

Hans Petter

I was wondering if it would be possible to include a basic Linux movie capture option?

I understand that the problem is a lack of a standard video-handling proceedure for Linux, but even a dialog that allowed us to capture a series of jpeg/png/etc files to a directory would be enough.

Joal Heagney