Using the MovieMaker plugin
The original documentation for this plugin is here.
Luckily, this plugin is very easy to use. What you must do however, is set up your trajectory (representations, resolution, speed, etc) before you start making movies. It is easy to fix these things using the main VMD window rather than the Movie plugin itself. Take a few minutes to make sure you scene is the way you want it before you adjust any Movie Maker settings. Generally, we won’t change the “Movie Duration” setting at all. “Set working directory” dictates where both the finished movie and the temporary render files are written. You should set this to a directory you can find easily, both to delete any leftover files, and so you can actually find your movie!
The first pull-down sets the rendering engine. “Snapshot” uses a screen grab of the VMD window. This is the least desirable option, as you must leave the VMD window on top, and uncovered by other windows. (Under OS X and UNIX (linux), the options show below are available.) Generally, “Internal Tachyon” is the easiest to use. In fact, this has recently been re-written to use the computer's GPU, which really speeds things up.
Next, examine the "Format" pull-down. This is the most hassle to work out, as the defaults really leave a lot to be desired. The best way to make a good-looking movie is to select "MPEG-2 NTSC DVD (ffmpeg). Download the ffmpeg binary, and follow these steps in a terminal window (not tkcon!) in order to get it to work. Make sure to quit VMD before you do this. (remember, what you enter into the terminal is in red)
- make a directory to store this and other programs. /Users/yourname/bin (you may also refer to this as '~/bin'). mkdir ~/bin
- move the ffmpeg binary (program) there (this assumes that it went to your "Downloads" directory): mv ~/Downloads/ffmpeg ~/bin
- make the program file run-able: chmod 755 ~/bin/ffmpeg
- You can run this program by giving the full path: ~/bin/ffmpeg; however VMD must be able to find it too.
- now you have to tell your terminal/shell/VMD where to find it. You may have a file called ".profile" in ~/ (home directory). If you have it, you will append a line to it. If you don't, you will create it. Please note" "<cntrl>-D" means press the
on your keyboard. Do not type "cntrl-D"!
a) if it lists the file, it exists, and you will append to it. Enter the following three lines at the prompt:
cat >> ~/.profile
PATH=~/bin:$PATH; export PATH
<cntrl>-D
(your prompt should return)
b) if it returns ls: .profile: No such file or directory, the file does not exist and you must create it. Enter the following three lines at the prompt:
cat > ~/.profile
PATH=~/bin:$PATH; export PATH
<cntrl>-D
(notice the similarity. The first cat command appends, the second one creates)
In either case, open a new terminal window and make sure it worked properly. Type which ffmpeg The response should be /Users/student/bin/ffmpeg (with your particular directories listed)
The other thing you should do is resize your VMD display window to approximately 2:1, as the DVD setting will output at this geometry, and if your VMD window does not start at this geometry, the result will look squashed.
ImageMagick is another possible renderer, but it is quite extensive and requires the installation of a lot of extra software using macports. It does make animated GIF files, however, which may make it worth the trouble. Here is an example. If you would like to do something like this, contact Prof. McCallum and he will help you.
The “Movie Settings” pull-down sets the direction of the trajectory. Caution: your trajectory will only play if either “Trajectory” or “Trajectory Rock” is chosen --- the first two choices will display a single frame of the molecule (but it will rotate them as noted). The other choices dictate some rendering options. “Image Smoothing” is what it sounds like; generally it is better to set your render resolution high (in the Graphical Representations window) if you have the graphics power and the time.
When you have the settings as you like them, click “Make Movie” and wait. Depending upon your machine and your settings, in a little while you will have your movie.