Hi John,
I saw Jean-Michel's post and as we all know there are several kinds of integrations of tinymce for various versions of moodle so here a guide how to add dragmath to your integration without a significant porting work
Download files from http://korpelainen.net/dragmxx.zip and unzip/add them over your existing integration. Files of dragmath will go to lib/dragmath folder and plugin (originally created by Glen Davies) to lib/editor/tinymce/jscripts/tiny_mce/plugins/
I had to modify only one of your files: lib/editor/tinymce/tinymcejs.php and there added 'dragmath' to
$theme_advanced_buttons = array(1 => array('bold', 'italic', 'underline', 'strikethrough', MENU_SEPARATOR, 'justifyleft', 'justifycenter', 'justifyright', 'justifyfull', MENU_SEPARATOR, 'formatselect', 'fontselect', 'fontsizeselect', MENU_SEPARATOR, 'undo', 'redo','dragmath'),
2 => array('cut', 'copy', 'paste', 'pastetext', 'pasteword', MENU_SEPARATOR, 'search', 'replace', MENU_SEPARATOR, 'bullist', 'numlist', MENU_SEPARATOR, 'outdent', 'indent', 'blockquote', MENU_SEPARATOR, 'link', 'unlink', 'anchor', 'image', 'cleanup', 'help', 'code', MENU_SEPARATOR, 'insertdate', 'inserttime', 'preview', MENU_SEPARATOR, 'forecolor', 'backcolor'),
3 => array('tablecontrols', MENU_SEPARATOR, 'hr', 'removeformat', 'visualaid', MENU_SEPARATOR, 'sub', 'sup', MENU_SEPARATOR, 'charmap', 'moodlesmileys', 'media', MENU_SEPARATOR, 'ltr', 'rtl', MENU_SEPARATOR, 'fullscreen'));
and to plugins list
$tinymceplugins = array('safari',
'pagebreak',
'layer',
'table',
'moodlesmileys',
'insertdatetime',
'preview',
'media',
'searchreplace',
'print',
'contextmenu',
'paste',
'directionality',
'fullscreen',
'noneditable',
'visualchars',
'nonbreaking',
'xhtmlxtras',
'template',
'inlinepopups',
'dragmath');
after changes refresh your browser and dragmath should be visible with default settings given in plugin files.
HTH,
Mauno