Applets are not allowed to print. To get around this restriction, Proof Designer has the Export HTML command. (There are two versions of the Export HTML command; the difference between them will be explained below.) When you give this command, Proof Designer will try to open a new web browser window and write your proof into that window. (Proof Designer does this by writing an HTML version of the proof into the window. That is why the command is called “Export HTML”.) You can then give your web browser's Print command to print your proof.
Not all browsers support the mechanism that Proof Designer uses to open a new web browser window. On the Macintosh, it should work fine in Safari 1.2 or newer, but to get it to work in other browsers you may need to install the Java Embedding Plugin. Also, some popup blockers prevent Proof Designer from opening a new web browser window, so you may need to turn off or reconfigure your popup blocker to get the Export HTML command to work. However, if you can't get the Export HTML command to work, all is not lost. If Proof Designer is unable to open a new web browser window, then it will write the HTML version of the proof to the Java Console. If you open the Java Console window (see below for more on how to do this), you should see the HTML. (You may have to scroll to the bottom of the window to see the HTML.) You can get the proof into a web browser window by creating a file containing the HTML. Copy the HTML from the Java Console window (beginning with “<!DOCTYPE HTML . . .” and ending with “</HTML>”) and paste it into a new text file in your favorite text processing program. Then save the file, and open it in your web browser. You should now be able to print the proof.
The HTML produced by Proof Designer may not display correctly in browsers that do not support css (cascading style sheets).
The two versions of the Export HTML command differ in the way they handle mathematical symbols. If you give the “Export HTML with gifs” command, then Proof Designer will write HTML in which mathematical symbols are represented by small picture files in gif format. This option should work reliably on any computer, as long as the computer is connected to the internet. (The computer must be connected to the internet in order to fetch the picture files for the mathematical symbols.) However, the pictures of mathematical symbols are fairly low resolution, and may not look good when printed. If your computer has fonts containing all the necessary mathematical symbols, then you may be able to get better printed results by using the “Export HTML with fonts” command. If you use this command and find that some of the symbols don't show up properly, you may be able to resolve the problem by changing the font settings in your browser. If you are not able to find a font setting that works, then you will have to stick with the “Export HTML with gifs” option.
I have found that mathematical symbols usually show up correctly on Macintosh computers without any changes to the font settings. In Windows, they show up correctly in some browsers but not others. In particular, I have found that they don't show up in Internet Explorer unless you change your font settings. (Changing these settings may affect your viewing of web pages in ways that you don't like, so you should probably make a note of your current settings before making any changes, so that you can change the settings back when you are done using Proof Designer.) To change your font settings in Internet Explorer, choose Internet Options from the Tools menu. Then click on Fonts. In the Language script pop-up menu select Latin based (it may already be selected), and then in the Web page font list select a font that includes mathematical symbols. Common fonts that should work are Arial Unicode MS and Lucida Sans Unicode. Most of the symbols will show up in Times New Roman, Arial, and Courier New, but some symbols may not. If you don't have these fonts then you'll have to experiment to see if some other font on your system will display the required symbols.
Your browser may have a command for opening the Java Console. In some browsers it is called the Java Message Window. On a Mac, you may find this command under a coffee cup icon on the right side of your menu bar. If not, you may need to change your Java preferences before you start your browser. Open your Applications folder, then open the Utilities folder inside the Applications folder, and start up the Java Preferences application. Under Advanced settings, choose Show Console. Then quit from Java Preferences and start up your browser.