11.1.21 is ready for release. This version contains one new item: adjustable translucency.
Up until now, Jmol has used a "screen window" technique for depicting translucent objects. The effect is as if looking through a screen on a window -- every other pixel is the object, every other the background. This model does not easily accomodate multiple translucent objects nor different levels of translucency. Jmol 11.1.21 introduces a new translucency model. In this model a translucent object both "emits" light of its color (so as to show up against a black background) and "transmits" color as though it were a color filter. The physical model is of a plastic filter that has a certain amount of reflectivity. The effect is that opaque objects behind a colored, translucent plane, for example, have colors changed in a "natural" sort of way. And if one translucent object is in front of another translucent object, then the obscured translucent object is still visible. The effect is quite remarkable. Halos, for example, pass over each other with just the right effect. A translucent isosurface has a "backside" that is visible THROUGH the front. The combination of translucent surfaces and slabbing produces an elegant rendition of a molecular pocket. To effect numerical translucency, just place a number after the word "translucent" anywhere that term could be used. Since this is a translucency measure, it runs from 0.0 (not translucent at all -- opaque) to 1.0 (invisible). Actually, we don't have 1.0 -- if you want to make something invisible in Jmol, just turn it off! (We might introduce the opposite, "opacity," after the keyoword OPAQUE, but that is really not necessary, and I have chosen to leave that out for now.) Actually, we have only three levels of translucency for now: 50%, 75%, and 82.5%. These can be selected using 0.5, 0.75, or 0.825 for the translucency number. These numbers can also be expressed on a 0-256 scale: 128, 192, and 224, but that is probably harder to remember. Other numbers work -- 0.3 will give you 0.5; 0.7 will give you 0.75; 0.8 will give you 0.825, but I recommend using the specified values, as in the future we may introduce a wider set of possibilities. You can specify the "old" translucency using -1: color xxxx translucent -1 This gives the screen-effect translucency. It may be removed in the future, but it is still there. The default translucency is 0.5 (when "translucent" is used by itself), but you can set that to anything, including -1. Please let me know if problems arise with this new translucency. It does require a bit more memory, because the opaque and translucent objects have to be kept track of separately as the image is built. One other issue is that in order to implement this real-time I had to cheat a bit. When you have three translucent objects, it is possible for the rear two to be shown incorrectly -- with the wrong one in front. The opaque objects and the front translucent object are always shown correctly, and if there are only two translucent objects, then they will be shown correctly. But if you start lining up multiple translucent objects and looking closely, you will see some oddities. I'm hoping what we have is a reasonable compromise. ------------ Bob Hanson ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Jmol-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/jmol-users
