Hi there, I use Corel Paint Shop Pro Photo X2.
Do I have to flatten layers before saving as PNG file? If so, do I Merge All (flatten) or Merge Visible? Thanks in advance.

PNG doesn't allow object or layer saving, so it should be automatic. You may get a dialog box regarding this when you save as png, you may not, depending upon the program. But in any event, if it successfully saves it as a png file, it has been "flattened."

That's what I thought but wasn't sure.
Thanks KLC Lewis and have a good day!

Just to be on the safe side I want to add that I start with a PSPImage with layers of graphics and text. So if I save that as PNG file, it will be flattened automatically, right?

Please ignore my last question. I read your answer again and it's all clear to me now. Thanks again.

I use Ulead PhotoImpact12, which works with objects and layers in .ufo format. I save the project regularly in .ufo until it's finished, then do the final save in .png and sometimes .jpg format. The conversion from layers and objects to "flattened" format, i.e. no objects, only one image layer, is an automatic function of saving to a format that doesn't allow layers and objects, so I would say "Yes," you are correct.

You will want to pay attention to what happens with the automatic process. They don't always use the same terminology but in Photoshop "flatten" means transparency goes away everything is saved as "background". So in Photoshop to preserver transparency one would want to manually delete any unused (invisible) layers then "merge layers." Although this is not a Photoshop question, do watch for that. (FWIW - in photoshop "Save for Web" automatically merges layers, not flattens, while "Save As" png prompts to flatten - same program, different default process)

Thanks Diane.