> Miguel, do you remember how you implemented the transparent > background? I remember you decided that that was what was > slowing down the rendering on your machine, but still, I'd > like to experiment. > > Bob
Bob, My recollection is that the problem with transparent background was more than a performance problem. Here is what I have been able to dredge up. I think that I started down the path to implement transparent background and was stopped abruptly when I realized that it could not be implemented with the graphics APIs that I had available to me in the Java AWT class libraries. Here's the scoop ... The Java AWT and/or the OS window manager (Windows/MacOS/Linux) assume that an overlaying window is fully opaque and fully paints the window. In addition, there is no way for an overlaying window to access the contents of an underlying window ... because it belongs to another application and the contents are ephemeral. So, when I used the alpha channel to make the Jmol background bits transparent here is what I saw. When I rotated the molecule it would blur on the screen, leaving a trail in all of the pixels where it had been painted. If I forced a repaint of the underlying window (by hitting Alt-Tab twice, for example) then it would look fine ... until I rotated the molecule. Now, I suspect that much of this limitation was with the Java AWT class library. While I am not familiar with the OS window managers, I assume that they have some type of 'sprite' mechanism that allows them to support something like this. And the newer newer windowing class libraries very well may expose this functionality. So, you asked a separate question about Swing ... and that was probably motivated by this same issue ... I suggest that you find out whether or not Swing supports the ability to create non-rectangular windows/sprites with transparent pixels. If it does, then you should be able to adapt Jmol to use that mechanism in order to achieve the effect you want. If Swing (or Java2D) doesn't support the functionality then I don't think it can be done. Miguel ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Jmol-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/jmol-developers
