Situation

Now you are working on a huge file with over a thousand segments where each segment is a complex sentence with numerous clauses and clarifying statements, and thus takes three or four lines in the editor pane. Using OmegaT for this work is a blessing in itself, as you get only this much at a time,  and, not getting lost too easily, can concentrate on your work much better.

Problem

When this particular file is open, you experience some latency in OmegaT’s response to your keystrokes or mouse clicks. Not a huge problem, but considering the size of each segment and the level of mental concentration this slowdown is rather annoying.

Solution

A natural solution would be splitting the big file into several smaller ones. While it sounds easy enough, here’s several hints to make the whole process easier, smoother,and eventually, faster.

• The big file doesn’t need to be deleted or altered in any way. It stays where it is, and new smaller files are added to the project.
• New smaller files should be named in a consecutive manner (with numbers, for instance) and stored in a separate sub-folder within the project’s source folder. It’s not absolutely necessary, but giving the files consecutive names saves the flow of the text, and storing them in a separate sub-folder makes it much simpler to locate and delete them afterwards.
• 500-600 big segments in a file don’t seem to slow OmegaT down, so that can serve as a guideline when splitting the files.
• If it’s a markup file (html, xml etc.), use a plain text editor and avoid WYSIWYG editors. The reason for that is preserving the same tags as in the big file. So, you just copy a big chunk of text, paste it in a new file created in your text editor, give the resulting file a proper extension (the same as the original) and store it in the sub-folder within the source folder where these temporary files are stored.
• If it’s a odt or docx file, use “trimming” rather then copying and pasting. To do the trimming, copy the original to a new location, open it, scroll down to a section where the file should be split, and delete everything after that point. Then press Menu → Save as, give it a name and proper extension, and press Ok. Once it’s saved, press Ctrl+Z (Undo), and this time delete everything before that split point. Scroll down to the next split point and delete everything after the second split point. Now save under a new name. When saved, press Ctrl+Z, delete everything before the second split point, scroll down to the next split point… you get the picture.
• Once new files are produced and stored within the project source folder, reload/reopen the project (F5 in OmegaT), select the first one of them in Project Files window and start translating. All the segments might look somewhat grayish — that’s ok because now every segment in the smaller file has its counterpart in the original file. To disable this grayish representation of non-unique segments, remove the check from View → Mark Non-Unique segments.
• When creating translated documents in OmegaT (Ctrl+D), the huge file in target language will be created with the segments translated in the smaller ones.
• Once everything in the temporary files is translated, they can be deleted along with the sub-folder where they were. The original file should be checked one more to make sure there isn’t any problem with tags.

Here you can read more about non-unique segments in OmegaT: Auto-Propagation and Alternative Translations of Internal Repetitions in OmegaT

Another — not-so-obvious — solution would be hiding little gray dots that represent whitespace (in case it was enabled): View → Mark Whitespace. It considerably speeds OmegaT up on big files when those are not shown. LanguageTool from OmegaT plugins does a great job showing you double spaces and other whitespace related issues/typos; but then you always check for that at the QA stage, don’t you?

Good luck