American school children are familiar with the nursery rhyme that their parents would recite as they grabbed and wiggled each of their toes:
This little piggy went to market. This little piggy stayed home. This little piggy had roast beef. This little piggy had none. This little piggy cried wee wee wee all the way home.
This little DWG has six layers:
This little DWF has one:
Why? This was a recent topic of discussion in the DWF newsgroup. The sample DWF file was supplied by longtime DWF programmer Jos Groot Lipman. As an aside, when it comes to the DWF Toolkit, Jos is most knowledgeable non-Autodesk employee on the planet. Jos has been working with DWF for a long time. He regularly participates in the newsgroups. Jos contributes to what peer to peer newsgroups can accomplish.
So why does this DWF have only one layer yet the corresponding DWG has six? Software Quality Assurance Engineer, John Schmier, who has also worked with DWF since its inception, provided the answer:
I was able to publish the DWF file with a full list of layers by setting the Shaded viewport option, Shade plot, to "As displayed." (Jos had it set to Hidden.) For some reason, AutoCAD places all objects on the same layer when this value is set to Hidden.
John made this change by selecting the model space tab, issuing a Page Setup command, and changing the Shade Mode value found on the right side of the dialog box.
After republishing, this little DWF has six layers:
This has been logged as an AutoCAD issue; however there's no reason to cry all the way home about it. It may be corrected in a future release. For now, just don't set the Shade plot option to Hidden when publishing DWF.